The commit referenced in the Fixes tag incorrectly accounted the number
of in-flight fds over a unix domain socket to the original opener
of the file-descriptor. This allows another process to arbitrary
deplete the original file-openers resource limit for the maximum of
open files. Instead the sending processes and its struct cred should
be credited.
To do so, we add a reference counted struct user_struct pointer to the
scm_fp_list and use it to account for the number of inflight unix fds.
Fixes: 712f4aad40 ("unix: properly account for FDs passed over unix sockets")
Reported-by: David Herrmann <dh.herrmann@gmail.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove a write-only stack variable from unix_attach_fds(). This is a
left-over from the security fix in:
commit 712f4aad40
Author: willy tarreau <w@1wt.eu>
Date: Sun Jan 10 07:54:56 2016 +0100
unix: properly account for FDs passed over unix sockets
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Dmitry reported a struct pid leak detected by a syzkaller program.
Bug happens in unix_stream_recvmsg() when we break the loop when a
signal is pending, without properly releasing scm.
Fixes: b3ca9b02b0 ("net: fix multithreaded signal handling in unix recv routines")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/bonding/bond_main.c
drivers/net/ethernet/mellanox/mlxsw/spectrum.h
drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
The bond_main.c and mellanox switch conflicts were cases of
overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
It is possible for a process to allocate and accumulate far more FDs than
the process' limit by sending them over a unix socket then closing them
to keep the process' fd count low.
This change addresses this problem by keeping track of the number of FDs
in flight per user and preventing non-privileged processes from having
more FDs in flight than their configured FD limit.
Reported-by: socketpair@gmail.com
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Mitigates: CVE-2013-4312 (Linux 2.0+)
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>
On 2015/11/06, Dmitry Vyukov reported a deadlock involving the splice
system call and AF_UNIX sockets,
http://lists.openwall.net/netdev/2015/11/06/24
The situation was analyzed as
(a while ago) A: socketpair()
B: splice() from a pipe to /mnt/regular_file
does sb_start_write() on /mnt
C: try to freeze /mnt
wait for B to finish with /mnt
A: bind() try to bind our socket to /mnt/new_socket_name
lock our socket, see it not bound yet
decide that it needs to create something in /mnt
try to do sb_start_write() on /mnt, block (it's
waiting for C).
D: splice() from the same pipe to our socket
lock the pipe, see that socket is connected
try to lock the socket, block waiting for A
B: get around to actually feeding a chunk from
pipe to file, try to lock the pipe. Deadlock.
on 2015/11/10 by Al Viro,
http://lists.openwall.net/netdev/2015/11/10/4
The patch fixes this by removing the kern_path_create related code from
unix_mknod and executing it as part of unix_bind prior acquiring the
readlock of the socket in question. This means that A (as used above)
will sb_start_write on /mnt before it acquires the readlock, hence, it
won't indirectly block B which first did a sb_start_write and then
waited for a thread trying to acquire the readlock. Consequently, A
being blocked by C waiting for B won't cause a deadlock anymore
(effectively, both A and B acquire two locks in opposite order in the
situation described above).
Dmitry Vyukov(<dvyukov@google.com>) tested the original patch.
Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/geneve.c
Here we had an overlapping change, where in 'net' the extraneous stats
bump was being removed whilst in 'net-next' the final argument to
udp_tunnel6_xmit_skb() was being changed.
Signed-off-by: David S. Miller <davem@davemloft.net>
With b3ca9b02b0, the AF_UNIX SOCK_STREAM
receive code was changed from using mutex_lock(&u->readlock) to
mutex_lock_interruptible(&u->readlock) to prevent signals from being
delayed for an indefinite time if a thread sleeping on the mutex
happened to be selected for handling the signal. But this was never a
problem with the stream receive code (as opposed to its datagram
counterpart) as that never went to sleep waiting for new messages with the
mutex held and thus, wouldn't cause secondary readers to block on the
mutex waiting for the sleeping primary reader. As the interruptible
locking makes the code more complicated in exchange for no benefit,
change it back to using mutex_lock.
Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current unix_dgram_recvsmg code acquires the u->readlock mutex in
order to protect access to the peek offset prior to calling
__skb_recv_datagram for actually receiving data. This implies that a
blocking reader will go to sleep with this mutex held if there's
presently no data to return to userspace. Two non-desirable side effects
of this are that a later non-blocking read call on the same socket will
block on the ->readlock mutex until the earlier blocking call releases it
(or the readers is interrupted) and that later blocking read calls
will wait longer than the effective socket read timeout says they
should: The timeout will only start 'ticking' once such a reader hits
the schedule_timeout in wait_for_more_packets (core.c) while the time it
already had to wait until it could acquire the mutex is unaccounted for.
The patch avoids both by using the __skb_try_recv_datagram and
__skb_wait_for_more packets functions created by the first patch to
implement a unix_dgram_recvmsg read loop which releases the readlock
mutex prior to going to sleep and reacquires it as needed
afterwards. Non-blocking readers will thus immediately return with
-EAGAIN if there's no data available regardless of any concurrent
blocking readers and all blocking readers will end up sleeping via
schedule_timeout, thus honouring the configured socket receive timeout.
Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/renesas/ravb_main.c
kernel/bpf/syscall.c
net/ipv4/ipmr.c
All three conflicts were cases of overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is a cleanup to make following patch easier to
review.
Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
from (struct socket)->flags to a (struct socket_wq)->flags
to benefit from RCU protection in sock_wake_async()
To ease backports, we rename both constants.
Two new helpers, sk_set_bit(int nr, struct sock *sk)
and sk_clear_bit(int net, struct sock *sk) are added so that
following patch can change their implementation.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current unix_dgram_recvmsg does a wake up for every received
datagram. This seems wasteful as only SOCK_DGRAM client sockets in an
n:1 association with a server socket will ever wait because of the
associated condition. The patch below changes the function such that the
wake up only happens if wq_has_sleeper indicates that someone actually
wants to be notified. Testing with SOCK_SEQPACKET and SOCK_DGRAM socket
seems to confirm that this is an improvment.
Signed-Off-By: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sendpage did not care about credentials at all. This could lead to
situations in which because of fd passing between processes we could
append data to skbs with different scm data. It is illegal to splice those
skbs together. Instead we have to allocate a new skb and if requested
fill out the scm details.
Fixes: 869e7c6248 ("net: af_unix: implement stream sendpage support")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The memory barrier in the helper wq_has_sleeper is needed by just
about every user of waitqueue_active. This patch generalises it
by making it take a wait_queue_head_t directly. The existing
helper is renamed to skwq_has_sleeper.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rainer Weikusat <rweikusat@mobileactivedefense.com> writes:
An AF_UNIX datagram socket being the client in an n:1 association with
some server socket is only allowed to send messages to the server if the
receive queue of this socket contains at most sk_max_ack_backlog
datagrams. This implies that prospective writers might be forced to go
to sleep despite none of the message presently enqueued on the server
receive queue were sent by them. In order to ensure that these will be
woken up once space becomes again available, the present unix_dgram_poll
routine does a second sock_poll_wait call with the peer_wait wait queue
of the server socket as queue argument (unix_dgram_recvmsg does a wake
up on this queue after a datagram was received). This is inherently
problematic because the server socket is only guaranteed to remain alive
for as long as the client still holds a reference to it. In case the
connection is dissolved via connect or by the dead peer detection logic
in unix_dgram_sendmsg, the server socket may be freed despite "the
polling mechanism" (in particular, epoll) still has a pointer to the
corresponding peer_wait queue. There's no way to forcibly deregister a
wait queue with epoll.
Based on an idea by Jason Baron, the patch below changes the code such
that a wait_queue_t belonging to the client socket is enqueued on the
peer_wait queue of the server whenever the peer receive queue full
condition is detected by either a sendmsg or a poll. A wake up on the
peer queue is then relayed to the ordinary wait queue of the client
socket via wake function. The connection to the peer wait queue is again
dissolved if either a wake up is about to be relayed or the client
socket reconnects or a dead peer is detected or the client socket is
itself closed. This enables removing the second sock_poll_wait from
unix_dgram_poll, thus avoiding the use-after-free, while still ensuring
that no blocked writer sleeps forever.
Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Fixes: ec0d215f94 ("af_unix: fix 'poll for write'/connected DGRAM sockets")
Reviewed-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While possibly in future we don't necessarily need to use
sk_buff_head.lock this is a rather larger change, as it affects the
af_unix fd garbage collector, diag and socket cleanups. This is too much
for a stable patch.
For the time being grab sk_buff_head.lock without disabling bh and irqs,
so don't use locked skb_queue_tail.
Fixes: 869e7c6248 ("net: af_unix: implement stream sendpage support")
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Reported-by: Eric Dumazet <edumazet@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case multiple writes to a unix stream socket race we could end up in a
situation where we pre-allocate a new skb for use in unix_stream_sendpage
but have to free it again in the locked section because another skb
has been appended meanwhile, which we must use. Accidentally we didn't
clear the pointer after consuming it and so we touched freed memory
while appending it to the sk_receive_queue. So, clear the pointer after
consuming the skb.
This bug has been found with syzkaller
(http://github.com/google/syzkaller) by Dmitry Vyukov.
Fixes: 869e7c6248 ("net: af_unix: implement stream sendpage support")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
During splicing an af-unix socket to a pipe we have to drop all
af-unix socket locks. While doing so we allow another reader to enter
unix_stream_read_generic which can read, copy and finally free another
skb. If exactly this skb is just in process of being spliced we get a
use-after-free report by kasan.
First, we must make sure to not have a free while the skb is used during
the splice operation. We simply increment its use counter before unlocking
the reader lock.
Stream sockets have the nice characteristic that we don't care about
zero length writes and they never reach the peer socket's queue. That
said, we can take the UNIXCB.consumed field as the indicator if the
skb was already freed from the socket's receive queue. If the skb was
fully consumed after we locked the reader side again we know it has been
dropped by a second reader. We indicate a short read to user space and
abort the current splice operation.
This bug has been found with syzkaller
(http://github.com/google/syzkaller) by Dmitry Vyukov.
Fixes: 2b514574f7 ("net: af_unix: implement splice for stream af_unix sockets")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
poll(POLLOUT) on a listener should not report fd is ready for
a write().
This would break some applications using poll() and pfd.events = -1,
as they would not block in poll()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Alan Burlison <Alan.Burlison@oracle.com>
Tested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now send with MSG_PEEK can return data from multiple SKBs.
Unfortunately we take into account the peek offset for each skb,
that is wrong. We need to apply the peek offset only once.
In addition, the peek offset should be used only if MSG_PEEK is set.
Cc: "David S. Miller" <davem@davemloft.net> (maintainer:NETWORKING
Cc: Eric Dumazet <edumazet@google.com> (commit_signer:1/14=7%)
Cc: Aaron Conole <aconole@bytheb.org>
Fixes: 9f389e3567 ("af_unix: return data from multiple SKBs on recv() with MSG_PEEK flag")
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Tested-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
AF_UNIX sockets now return multiple skbs from recv() when MSG_PEEK flag
is set.
This is referenced in kernel bugzilla #12323 @
https://bugzilla.kernel.org/show_bug.cgi?id=12323
As described both in the BZ and lkml thread @
http://lkml.org/lkml/2008/1/8/444 calling recv() with MSG_PEEK on an
AF_UNIX socket only reads a single skb, where the desired effect is
to return as much skb data has been queued, until hitting the recv
buffer size (whichever comes first).
The modified MSG_PEEK path will now move to the next skb in the tree
and jump to the again: label, rather than following the natural loop
structure. This requires duplicating some of the loop head actions.
This was tested using the python socketpair python code attached to
the bugzilla issue.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
SCM_SECURITY was originally only implemented for datagram sockets,
not for stream sockets. However, SCM_CREDENTIALS is supported on
Unix stream sockets. For consistency, implement Unix stream support
for SCM_SECURITY as well. Also clean up the existing code and get
rid of the superfluous UNIXSID macro.
Motivated by https://bugzilla.redhat.com/show_bug.cgi?id=1224211,
where systemd was using SCM_CREDENTIALS and assumed wrongly that
SCM_SECURITY was also supported on Unix stream sockets.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/phy/amd-xgbe-phy.c
drivers/net/wireless/iwlwifi/Kconfig
include/net/mac80211.h
iwlwifi/Kconfig and mac80211.h were both trivial overlapping
changes.
The drivers/net/phy/amd-xgbe-phy.c file got removed in 'net-next' and
the bug fix that happened on the 'net' side is already integrated
into the rest of the amd-xgbe driver.
Signed-off-by: David S. Miller <davem@davemloft.net>
got a rare NULL pointer dereference in clear_bit
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
----
v2: switch to sock_flag(sk, SOCK_DEAD) and added net/caif/caif_socket.c
v3: return -ECONNRESET in upstream caller of wait function for SOCK_DEAD
Signed-off-by: David S. Miller <davem@davemloft.net>
unix_stream_recvmsg is refactored to unix_stream_read_generic in this
patch and enhanced to deal with pipe splicing. The refactoring is
inneglible, we mostly have to deal with a non-existing struct msghdr
argument.
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements sendpage support for AF_UNIX SOCK_STREAM
sockets. This is also required for a complete splice implementation.
The implementation is a bit tricky because we append to already existing
skbs and so have to hold unix_sk->readlock to protect the reading side
from either advancing UNIXCB.consumed or freeing the skb at the socket
receive tail.
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) mlx4 doesn't check fully for supported valid RSS hash function, fix
from Amir Vadai
2) Off by one in ibmveth_change_mtu(), from David Gibson
3) Prevent altera chip from reporting false error interrupts in some
circumstances, from Chee Nouk Phoon
4) Get rid of that stupid endless loop trying to allocate a FIN packet
in TCP, and in the process kill deadlocks. From Eric Dumazet
5) Fix get_rps_cpus() crash due to wrong invalid-cpu value, also from
Eric Dumazet
6) Fix two bugs in async rhashtable resizing, from Thomas Graf
7) Fix topology server listener socket namespace bug in TIPC, from Ying
Xue
8) Add some missing HAS_DMA kconfig dependencies, from Geert
Uytterhoeven
9) bgmac driver intends to force re-polling but does so by returning
the wrong value from it's ->poll() handler. Fix from Rafał Miłecki
10) When the creater of an rhashtable configures a max size for it,
don't bark in the logs and drop insertions when that is exceeded.
Fix from Johannes Berg
11) Recover from out of order packets in ppp mppe properly, from Sylvain
Rochet
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (41 commits)
bnx2x: really disable TPA if 'disable_tpa' option is set
net:treewide: Fix typo in drivers/net
net/mlx4_en: Prevent setting invalid RSS hash function
mdio-mux-gpio: use new gpiod_get_array and gpiod_put_array functions
netfilter; Add some missing default cases to switch statements in nft_reject.
ppp: mppe: discard late packet in stateless mode
ppp: mppe: sanity error path rework
net/bonding: Make DRV macros private
net: rfs: fix crash in get_rps_cpus()
altera tse: add support for fixed-links.
pxa168: fix double deallocation of managed resources
net: fix crash in build_skb()
net: eth: altera: Resolve false errors from MSGDMA to TSE
ehea: Fix memory hook reference counting crashes
net/tg3: Release IRQs on permanent error
net: mdio-gpio: support access that may sleep
inet: fix possible panic in reqsk_queue_unlink()
rhashtable: don't attempt to grow when at max_size
bgmac: fix requests for extra polling calls from NAPI
tcp: avoid looping in tcp_send_fin()
...
fixed several comment and whitespace style issues
Signed-off-by: Jason Eastman <eastman.jason.linux@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
places where we are dealing with S_ISSOCK file creation/lookups.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
AF_UNIX sockets should call mknod on the top layer only and should not attempt
to modify the lower layer in a layered filesystem such as overlayfs.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
After TIPC doesn't depend on iocb argument in its internal
implementations of sendmsg() and recvmsg() hooks defined in proto
structure, no any user is using iocb argument in them at all now.
Then we can drop the redundant iocb argument completely from kinds of
implementations of both sendmsg() and recvmsg() in the entire
networking stack.
Cc: Christoph Hellwig <hch@lst.de>
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The sock_iocb structure is allocate on stack for each read/write-like
operation on sockets, and contains various fields of which only the
embedded msghdr and sometimes a pointer to the scm_cookie is ever used.
Get rid of the sock_iocb and put a msghdr directly on the stack and pass
the scm_cookie explicitly to netlink_mmap_sendmsg.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.
This makes the very common pattern of
if (genlmsg_end(...) < 0) { ... }
be a whole bunch of dead code. Many places also simply do
return nlmsg_end(...);
and the caller is expected to deal with it.
This also commonly (at least for me) causes errors, because it is very
common to write
if (my_function(...))
/* error condition */
and if my_function() does "return nlmsg_end()" this is of course wrong.
Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.
Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did
- return nlmsg_end(...);
+ nlmsg_end(...);
+ return 0;
I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.
One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Note that the code _using_ ->msg_iter at that point will be very
unhappy with anything other than unshifted iovec-backed iov_iter.
We still need to convert users to proper primitives.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This encapsulates all of the skb_copy_datagram_iovec() callers
with call argument signature "skb, offset, msghdr->msg_iov, length".
When we move to iov_iters in the networking, the iov_iter object will
sit in the msghdr.
Having a helper like this means there will be less places to touch
during that transformation.
Based upon descriptions and patch from Al Viro.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking updates from David Miller:
1) Seccomp BPF filters can now be JIT'd, from Alexei Starovoitov.
2) Multiqueue support in xen-netback and xen-netfront, from Andrew J
Benniston.
3) Allow tweaking of aggregation settings in cdc_ncm driver, from Bjørn
Mork.
4) BPF now has a "random" opcode, from Chema Gonzalez.
5) Add more BPF documentation and improve test framework, from Daniel
Borkmann.
6) Support TCP fastopen over ipv6, from Daniel Lee.
7) Add software TSO helper functions and use them to support software
TSO in mvneta and mv643xx_eth drivers. From Ezequiel Garcia.
8) Support software TSO in fec driver too, from Nimrod Andy.
9) Add Broadcom SYSTEMPORT driver, from Florian Fainelli.
10) Handle broadcasts more gracefully over macvlan when there are large
numbers of interfaces configured, from Herbert Xu.
11) Allow more control over fwmark used for non-socket based responses,
from Lorenzo Colitti.
12) Do TCP congestion window limiting based upon measurements, from Neal
Cardwell.
13) Support busy polling in SCTP, from Neal Horman.
14) Allow RSS key to be configured via ethtool, from Venkata Duvvuru.
15) Bridge promisc mode handling improvements from Vlad Yasevich.
16) Don't use inetpeer entries to implement ID generation any more, it
performs poorly, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits)
rtnetlink: fix userspace API breakage for iproute2 < v3.9.0
tcp: fixing TLP's FIN recovery
net: fec: Add software TSO support
net: fec: Add Scatter/gather support
net: fec: Increase buffer descriptor entry number
net: fec: Factorize feature setting
net: fec: Enable IP header hardware checksum
net: fec: Factorize the .xmit transmit function
bridge: fix compile error when compiling without IPv6 support
bridge: fix smatch warning / potential null pointer dereference
via-rhine: fix full-duplex with autoneg disable
bnx2x: Enlarge the dorq threshold for VFs
bnx2x: Check for UNDI in uncommon branch
bnx2x: Fix 1G-baseT link
bnx2x: Fix link for KR with swapped polarity lane
sctp: Fix sk_ack_backlog wrap-around problem
net/core: Add VF link state control policy
net/fsl: xgmac_mdio is dependent on OF_MDIO
net/fsl: Make xgmac_mdio read error message useful
net_sched: drr: warn when qdisc is not work conserving
...
Using whole of allocated pages reduces requested skb->data size.
This is just a little more thriftily allocation.
netperf does not show difference with the current performance.
Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Several spots in the kernel perform a sequence like:
skb_queue_tail(&sk->s_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);
But at the moment we place the SKB onto the socket receive queue it
can be consumed and freed up. So this skb->len access is potentially
to freed up memory.
Furthermore, the skb->len can be modified by the consumer so it is
possible that the value isn't accurate.
And finally, no actual implementation of this callback actually uses
the length argument. And since nobody actually cared about it's
value, lots of call sites pass arbitrary values in such as '0' and
even '1'.
So just remove the length argument from the callback, that way there
is no confusion whatsoever and all of these use-after-free cases get
fixed as a side effect.
Based upon a patch by Eric Dumazet and his suggestion to audit this
issue tree-wide.
Signed-off-by: David S. Miller <davem@davemloft.net>
Some applications didn't expect recvmsg() on a non blocking socket
could return -EINTR. This possibility was added as a side effect
of commit b3ca9b02b0 ("net: fix multithreaded signal handling in
unix recv routines").
To hit this bug, you need to be a bit unlucky, as the u->readlock
mutex is usually held for very small periods.
Fixes: b3ca9b02b0 ("net: fix multithreaded signal handling in unix recv routines")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The unix socket code is using the result of csum_partial to
hash into a lookup table:
unix_hash_fold(csum_partial(sunaddr, len, 0));
csum_partial is only guaranteed to produce something that can be
folded into a checksum, as its prototype explains:
* returns a 32-bit number suitable for feeding into itself
* or csum_tcpudp_magic
The 32bit value should not be used directly.
Depending on the alignment, the ppc64 csum_partial will return
different 32bit partial checksums that will fold into the same
16bit checksum.
This difference causes the following testcase (courtesy of
Gustavo) to sometimes fail:
#include <sys/socket.h>
#include <stdio.h>
int main()
{
int fd = socket(PF_LOCAL, SOCK_STREAM|SOCK_CLOEXEC, 0);
int i = 1;
setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &i, 4);
struct sockaddr addr;
addr.sa_family = AF_LOCAL;
bind(fd, &addr, 2);
listen(fd, 128);
struct sockaddr_storage ss;
socklen_t sslen = (socklen_t)sizeof(ss);
getsockname(fd, (struct sockaddr*)&ss, &sslen);
fd = socket(PF_LOCAL, SOCK_STREAM|SOCK_CLOEXEC, 0);
if (connect(fd, (struct sockaddr*)&ss, sslen) == -1){
perror(NULL);
return 1;
}
printf("OK\n");
return 0;
}
As suggested by davem, fix this by using csum_fold to fold the
partial 32bit checksum into a 16bit checksum before using it.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a follow-up patch to f3d3342602 ("net: rework recvmsg
handler msg_name and msg_namelen logic").
DECLARE_SOCKADDR validates that the structure we use for writing the
name information to is not larger than the buffer which is reserved
for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR
consistently in sendmsg code paths.
Signed-off-by: Steffen Hurrle <steffen@hurrle.net>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/intel/i40e/i40e_main.c
drivers/net/macvtap.c
Both minor merge hassles, simple overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
This is similar to the set_peek_off patch where calling bind while the
socket is stuck in unix_dgram_recvmsg() will block and cause a hung task
spew after a while.
This is also the last place that did a straightforward mutex_lock(), so
there shouldn't be any more of these patches.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
unix_dgram_recvmsg() will hold the readlock of the socket until recv
is complete.
In the same time, we may try to setsockopt(SO_PEEK_OFF) which will hang until
unix_dgram_recvmsg() will complete (which can take a while) without allowing
us to break out of it, triggering a hung task spew.
Instead, allow set_peek_off to fail, this way userspace will not hang.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.
This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.
Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.
Also document these changes in include/linux/net.h as suggested by David
Miller.
Changes since RFC:
Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.
With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
msg->msg_name = NULL
".
This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.
Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.
Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the case of credentials passing in unix stream sockets (dgram
sockets seem not affected), we get a rather sparse race after
commit 16e5726 ("af_unix: dont send SCM_CREDENTIALS by default").
We have a stream server on receiver side that requests credential
passing from senders (e.g. nc -U). Since we need to set SO_PASSCRED
on each spawned/accepted socket on server side to 1 first (as it's
not inherited), it can happen that in the time between accept() and
setsockopt() we get interrupted, the sender is being scheduled and
continues with passing data to our receiver. At that time SO_PASSCRED
is neither set on sender nor receiver side, hence in cmsg's
SCM_CREDENTIALS we get eventually pid:0, uid:65534, gid:65534
(== overflow{u,g}id) instead of what we actually would like to see.
On the sender side, here nc -U, the tests in maybe_add_creds()
invoked through unix_stream_sendmsg() would fail, as at that exact
time, as mentioned, the sender has neither SO_PASSCRED on his side
nor sees it on the server side, and we have a valid 'other' socket
in place. Thus, sender believes it would just look like a normal
connection, not needing/requesting SO_PASSCRED at that time.
As reverting 16e5726 would not be an option due to the significant
performance regression reported when having creds always passed,
one way/trade-off to prevent that would be to set SO_PASSCRED on
the listener socket and allow inheriting these flags to the spawned
socket on server side in accept(). It seems also logical to do so
if we'd tell the listener socket to pass those flags onwards, and
would fix the race.
Before, strace:
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"blub\n", 4096}],
msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET,
cmsg_type=SCM_CREDENTIALS{pid=0, uid=65534, gid=65534}},
msg_flags=0}, 0) = 5
After, strace:
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"blub\n", 4096}],
msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET,
cmsg_type=SCM_CREDENTIALS{pid=11580, uid=1000, gid=1000}},
msg_flags=0}, 0) = 5
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When filling the netlink message we miss to wipe the pad field,
therefore leak one byte of heap memory to userland. Fix this by
setting pad to 0.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit e370a72363 ("af_unix: improve STREAM behavior with fragmented
memory") added a bug on large send() because the
skb_copy_datagram_from_iovec() call always start from the beginning
of iovec.
We must instead use the @sent variable to properly skip the
already processed part.
Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adding paged frags skbs to af_unix sockets introduced a performance
regression on large sends because of additional page allocations, even
if each skb could carry at least 100% more payload than before.
We can instruct sock_alloc_send_pskb() to attempt high order
allocations.
Most of the time, it does a single page allocation instead of 8.
I added an additional parameter to sock_alloc_send_pskb() to
let other users to opt-in for this new feature on followup patches.
Tested:
Before patch :
$ netperf -t STREAM_STREAM
STREAM STREAM TEST
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec
2304 212992 212992 10.00 46861.15
After patch :
$ netperf -t STREAM_STREAM
STREAM STREAM TEST
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec
2304 212992 212992 10.00 57981.11
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
unix_stream_sendmsg() currently uses order-2 allocations,
and we had numerous reports this can fail.
The __GFP_REPEAT flag present in sock_alloc_send_pskb() is
not helping.
This patch extends the work done in commit eb6a24816b
("af_unix: reduce high order page allocations) for
datagram sockets.
This opens the possibility of zero copy IO (splice() and
friends)
The trick is to not use skb_pull() anymore in recvmsg() path,
and instead add a @consumed field in UNIXCB() to track amount
of already read payload in the skb.
There is a performance regression for large sends
because of extra page allocations that will be addressed
in a follow-up patch, allowing sock_alloc_send_pskb()
to attempt high order page allocations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking updates from David Miller:
"This is a re-do of the net-next pull request for the current merge
window. The only difference from the one I made the other day is that
this has Eliezer's interface renames and the timeout handling changes
made based upon your feedback, as well as a few bug fixes that have
trickeled in.
Highlights:
1) Low latency device polling, eliminating the cost of interrupt
handling and context switches. Allows direct polling of a network
device from socket operations, such as recvmsg() and poll().
Currently ixgbe, mlx4, and bnx2x support this feature.
Full high level description, performance numbers, and design in
commit 0a4db187a9 ("Merge branch 'll_poll'")
From Eliezer Tamir.
2) With the routing cache removed, ip_check_mc_rcu() gets exercised
more than ever before in the case where we have lots of multicast
addresses. Use a hash table instead of a simple linked list, from
Eric Dumazet.
3) Add driver for Atheros CQA98xx 802.11ac wireless devices, from
Bartosz Markowski, Janusz Dziedzic, Kalle Valo, Marek Kwaczynski,
Marek Puzyniak, Michal Kazior, and Sujith Manoharan.
4) Support reporting the TUN device persist flag to userspace, from
Pavel Emelyanov.
5) Allow controlling network device VF link state using netlink, from
Rony Efraim.
6) Support GRE tunneling in openvswitch, from Pravin B Shelar.
7) Adjust SOCK_MIN_RCVBUF and SOCK_MIN_SNDBUF for modern times, from
Daniel Borkmann and Eric Dumazet.
8) Allow controlling of TCP quickack behavior on a per-route basis,
from Cong Wang.
9) Several bug fixes and improvements to vxlan from Stephen
Hemminger, Pravin B Shelar, and Mike Rapoport. In particular,
support receiving on multiple UDP ports.
10) Major cleanups, particular in the area of debugging and cookie
lifetime handline, to the SCTP protocol code. From Daniel
Borkmann.
11) Allow packets to cross network namespaces when traversing tunnel
devices. From Nicolas Dichtel.
12) Allow monitoring netlink traffic via AF_PACKET sockets, in a
manner akin to how we monitor real network traffic via ptype_all.
From Daniel Borkmann.
13) Several bug fixes and improvements for the new alx device driver,
from Johannes Berg.
14) Fix scalability issues in the netem packet scheduler's time queue,
by using an rbtree. From Eric Dumazet.
15) Several bug fixes in TCP loss recovery handling, from Yuchung
Cheng.
16) Add support for GSO segmentation of MPLS packets, from Simon
Horman.
17) Make network notifiers have a real data type for the opaque
pointer that's passed into them. Use this to properly handle
network device flag changes in arp_netdev_event(). From Jiri
Pirko and Timo Teräs.
18) Convert several drivers over to module_pci_driver(), from Peter
Huewe.
19) tcp_fixup_rcvbuf() can loop 500 times over loopback, just use a
O(1) calculation instead. From Eric Dumazet.
20) Support setting of explicit tunnel peer addresses in ipv6, just
like ipv4. From Nicolas Dichtel.
21) Protect x86 BPF JIT against spraying attacks, from Eric Dumazet.
22) Prevent a single high rate flow from overruning an individual cpu
during RX packet processing via selective flow shedding. From
Willem de Bruijn.
23) Don't use spinlocks in TCP md5 signing fast paths, from Eric
Dumazet.
24) Don't just drop GSO packets which are above the TBF scheduler's
burst limit, chop them up so they are in-bounds instead. Also
from Eric Dumazet.
25) VLAN offloads are missed when configured on top of a bridge, fix
from Vlad Yasevich.
26) Support IPV6 in ping sockets. From Lorenzo Colitti.
27) Receive flow steering targets should be updated at poll() time
too, from David Majnemer.
28) Fix several corner case regressions in PMTU/redirect handling due
to the routing cache removal, from Timo Teräs.
29) We have to be mindful of ipv4 mapped ipv6 sockets in
upd_v6_push_pending_frames(). From Hannes Frederic Sowa.
30) Fix L2TP sequence number handling bugs, from James Chapman."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1214 commits)
drivers/net: caif: fix wrong rtnl_is_locked() usage
drivers/net: enic: release rtnl_lock on error-path
vhost-net: fix use-after-free in vhost_net_flush
net: mv643xx_eth: do not use port number as platform device id
net: sctp: confirm route during forward progress
virtio_net: fix race in RX VQ processing
virtio: support unlocked queue poll
net/cadence/macb: fix bug/typo in extracting gem_irq_read_clear bit
Documentation: Fix references to defunct linux-net@vger.kernel.org
net/fs: change busy poll time accounting
net: rename low latency sockets functions to busy poll
bridge: fix some kernel warning in multicast timer
sfc: Fix memory leak when discarding scattered packets
sit: fix tunnel update via netlink
dt:net:stmmac: Add dt specific phy reset callback support.
dt:net:stmmac: Add support to dwmac version 3.610 and 3.710
dt:net:stmmac: Allocate platform data only if its NULL.
net:stmmac: fix memleak in the open method
ipv6: rt6_check_neigh should successfully verify neigh if no NUD information are available
net: ipv6: fix wrong ping_v6_sendmsg return value
...
Reduce the uses of this unnecessary typedef.
Done via perl script:
$ git grep --name-only -w ctl_table net | \
xargs perl -p -i -e '\
sub trim { my ($local) = @_; $local =~ s/(^\s+|\s+$)//g; return $local; } \
s/\b(?<!struct\s)ctl_table\b(\s*\*\s*|\s+\w+)/"struct ctl_table " . trim($1)/ge'
Reflow the modified lines that now exceed 80 columns.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Avoid waking up every thread sleeping in read call on an AF_UNIX
socket during suspend and resume by calling a freezable blocking
call. Previous patches modified the freezer to avoid sending
wakeups to threads that are blocked in freezable blocking calls.
This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Using bit fields is dangerous on ppc64/sparc64, as the compiler [1]
uses 64bit instructions to manipulate them.
If the 64bit word includes any atomic_t or spinlock_t, we can lose
critical concurrent changes.
This is happening in af_unix, where unix_sk(sk)->gc_candidate/
gc_maybe_cycle/lock share the same 64bit word.
This leads to fatal deadlock, as one/several cpus spin forever
on a spinlock that will never be available again.
A safer way would be to use a long to store flags.
This way we are sure compiler/arch wont do bad things.
As we own unix_gc_lock spinlock when clearing or setting bits,
we can use the non atomic __set_bit()/__clear_bit().
recursion_level can share the same 64bit location with the spinlock,
as it is set only with this spinlock held.
[1] bug fixed in gcc-4.8.0 :
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52080
Reported-by: Ambrose Feinstein <ambrose@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
drivers/net/ethernet/emulex/benet/be.h
include/net/tcp.h
net/mac802154/mac802154.h
Most conflicts were minor overlapping stuff.
The be2net driver brought in some fixes that added __vlan_put_tag
calls, which in net-next take an additional argument.
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, peeking on a unix stream socket with an offset larger than len of
the data in the sk receive queue returns immediately with bogus data.
This patch fixes this so that the behavior is the same as peeking with no
offset on an empty queue: the caller blocks.
Signed-off-by: Benjamin Poirier <bpoirier@suse.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/emulex/benet/be_main.c
drivers/net/ethernet/intel/igb/igb_main.c
drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
include/net/scm.h
net/batman-adv/routing.c
net/ipv4/tcp_input.c
The e{uid,gid} --> {uid,gid} credentials fix conflicted with the
cleanup in net-next to now pass cred structs around.
The be2net driver had a bug fix in 'net' that overlapped with the VLAN
interface changes by Patrick McHardy in net-next.
An IGB conflict existed because in 'net' the build_skb() support was
reverted, and in 'net-next' there was a comment style fix within that
code.
Several batman-adv conflicts were resolved by making sure that all
calls to batadv_is_my_mac() are changed to have a new bat_priv first
argument.
Eric Dumazet's TS ECR fix in TCP in 'net' conflicted with the F-RTO
rewrite in 'net-next', mostly overlapping changes.
Thanks to Stephen Rothwell and Antonio Quartulli for help with several
of these merge resolutions.
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that uids and gids are completely encapsulated in kuid_t
and kgid_t we no longer need to pass struct cred which allowed
us to test both the uid and the user namespace for equality.
Passing struct cred potentially allows us to pass the entire group
list as BSD does but I don't believe the cost of cache line misses
justifies retaining code for a future potential application.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/nfc/microread/mei.c
net/netfilter/nfnetlink_queue_core.c
Pull in 'net' to get Eric Biederman's AF_UNIX fix, upon which
some cleanups are going to go on-top.
Signed-off-by: David S. Miller <davem@davemloft.net>
It was reported that the following LSB test case failed
https://lsbbugs.linuxfoundation.org/attachment.cgi?id=2144 because we
were not coallescing unix stream messages when the application was
expecting us to.
The problem was that the first send was before the socket was accepted
and thus sock->sk_socket was NULL in maybe_add_creds, and the second
send after the socket was accepted had a non-NULL value for sk->socket
and thus we could tell the credentials were not needed so we did not
bother.
The unnecessary credentials on the first message cause
unix_stream_recvmsg to start verifying that all messages had the same
credentials before coallescing and then the coallescing failed because
the second message had no credentials.
Ignoring credentials when we don't care in unix_stream_recvmsg fixes a
long standing pessimization which would fail to coallesce messages when
reading from a unix stream socket if the senders were different even if
we did not care about their credentials.
I have tested this and verified that the in the LSB test case mentioned
above that the messages do coallesce now, while the were failing to
coallesce without this change.
Reported-by: Karel Srot <ksrot@redhat.com>
Reported-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 14134f6584.
The problem that the above patch was meant to address is that af_unix
messages are not being coallesced because we are sending unnecesarry
credentials. Not sending credentials in maybe_add_creds totally
breaks unconnected unix domain sockets that wish to send credentails
to other sockets.
In practice this break some versions of udev because they receive a
message and the sending uid is bogus so they drop the message.
Reported-by: Sven Joachim <svenjoac@gmx.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 7d4c04fc17 ("net: add option to enable
error queue packets waking select") has an issue due to operator precedence
causing the bit-wise OR to bind to the sock_flags call instead of the result of
the terniary conditional. This fixes the *_poll functions to work properly. The
old code results in "mask |= POLLPRI" instead of what was intended, which is to
only include POLLPRI when the socket option is enabled.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, when a socket receives something on the error queue it only wakes up
the socket on select if it is in the "read" list, that is the socket has
something to read. It is useful also to wake the socket if it is in the error
list, which would enable software to wait on error queue packets without waking
up for regular data on the socket. The main use case is for receiving
timestamped transmit packets which return the timestamp to the socket via the
error queue. This enables an application to select on the socket for the error
queue only instead of for the regular traffic.
-v2-
* Added the SO_SELECT_ERR_QUEUE socket option to every architechture specific file
* Modified every socket poll function that checks error queue
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Cc: Jeffrey Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Matthew Vick <matthew.vick@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
SCM_SCREDENTIALS should apply to write() syscalls only either source or destination
socket asserted SOCK_PASSCRED. The original implememtation in maybe_add_creds is wrong,
and breaks several LSB testcases ( i.e. /tset/LSB.os/netowkr/recvfrom/T.recvfrom).
Origionally-authored-by: Karel Srot <ksrot@redhat.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As reported by Jan, and others over the past few years, there is a
race condition caused by unix_release setting the sock->sk pointer
to NULL before properly marking the socket as dead/orphaned. This
can cause a problem with the LSM hook security_unix_may_send() if
there is another socket attempting to write to this partially
released socket in between when sock->sk is set to NULL and it is
marked as dead/orphaned. This patch fixes this by only setting
sock->sk to NULL after the socket has been marked as dead; I also
take the opportunity to make unix_release_sock() a void function
as it only ever returned 0/success.
Dave, I think this one should go on the -stable pile.
Special thanks to Jan for coming up with a reproducer for this
problem.
Reported-by: Jan Stancek <jan.stancek@gmail.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I'm not sure why, but the hlist for each entry iterators were conceived
list_for_each_entry(pos, head, member)
The hlist ones were greedy and wanted an extra parameter:
hlist_for_each_entry(tpos, pos, head, member)
Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.
Besides the semantic patch, there was some manual work required:
- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.
The semantic patch which is mostly the work of Peter Senna Tschudin is here:
@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
type T;
expression a,c,d,e;
identifier b;
statement S;
@@
-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>
[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs pile (part one) from Al Viro:
"Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
locking violations, etc.
The most visible changes here are death of FS_REVAL_DOT (replaced with
"has ->d_weak_revalidate()") and a new helper getting from struct file
to inode. Some bits of preparation to xattr method interface changes.
Misc patches by various people sent this cycle *and* ocfs2 fixes from
several cycles ago that should've been upstream right then.
PS: the next vfs pile will be xattr stuff."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
saner proc_get_inode() calling conventions
proc: avoid extra pde_put() in proc_fill_super()
fs: change return values from -EACCES to -EPERM
fs/exec.c: make bprm_mm_init() static
ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
ocfs2: fix possible use-after-free with AIO
ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
target: writev() on single-element vector is pointless
export kernel_write(), convert open-coded instances
fs: encode_fh: return FILEID_INVALID if invalid fid_type
kill f_vfsmnt
vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
nfsd: handle vfs_getattr errors in acl protocol
switch vfs_getattr() to struct path
default SET_PERSONALITY() in linux/elf.h
ceph: prepopulate inodes only when request is aborted
d_hash_and_lookup(): export, switch open-coded instances
9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
9p: split dropping the acls from v9fs_set_create_acl()
...
proc_net_remove is only used to remove proc entries
that under /proc/net,it's not a general function for
removing proc entries of netns. if we want to remove
some proc entries which under /proc/net/stat/, we still
need to call remove_proc_entry.
this patch use remove_proc_entry to replace proc_net_remove.
we can remove proc_net_remove after this patch.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Right now, some modules such as bonding use proc_create
to create proc entries under /proc/net/, and other modules
such as ipv4 use proc_net_fops_create.
It looks a little chaos.this patch changes all of
proc_net_fops_create to proc_create. we can remove
proc_net_fops_create after this patch.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for supporting the creation of network namespaces
by unprivileged users, modify all of the per net sysctl exports
and refuse to allow them to unprivileged users.
This makes it safe for unprivileged users in general to access
per net sysctls, and allows sysctls to be exported to unprivileged
users on an individual basis as they are deemed safe.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make it simple -- just put new nlattr with just sk->sk_shutdown bits.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is a frequent mistake to confuse the netlink port identifier with a
process identifier. Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.
I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.
I have successfully built an allyesconfig kernel with this change.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Return -EINVAL rather than 0 given an invalid "mode" parameter.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso discovered that avahi and
potentially NetworkManager accept spoofed Netlink messages because of a
kernel bug. The kernel passes all-zero SCM_CREDENTIALS ancillary data
to the receiver if the sender did not provide such data, instead of not
including any such data at all or including the correct data from the
peer (as it is the case with AF_UNIX).
This bug was introduced in commit 16e5726269
(af_unix: dont send SCM_CREDENTIALS by default)
This patch forces passing credentials for netlink, as
before the regression.
Another fix would be to not add SCM_CREDENTIALS in
netlink messages if not provided by the sender, but it
might break some programs.
With help from Florian Weimer & Petr Matousek
This issue is designated as CVE-2012-3520
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Petr Matousek <pmatouse@redhat.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull second vfs pile from Al Viro:
"The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the
deadlock reproduced by xfstests 068), symlink and hardlink restriction
patches, plus assorted cleanups and fixes.
Note that another fsfreeze deadlock (emergency thaw one) is *not*
dealt with - the series by Fernando conflicts a lot with Jan's, breaks
userland ABI (FIFREEZE semantics gets changed) and trades the deadlock
for massive vfsmount leak; this is going to be handled next cycle.
There probably will be another pull request, but that stuff won't be
in it."
Fix up trivial conflicts due to unrelated changes next to each other in
drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c}
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
delousing target_core_file a bit
Documentation: Correct s_umount state for freeze_fs/unfreeze_fs
fs: Remove old freezing mechanism
ext2: Implement freezing
btrfs: Convert to new freezing mechanism
nilfs2: Convert to new freezing mechanism
ntfs: Convert to new freezing mechanism
fuse: Convert to new freezing mechanism
gfs2: Convert to new freezing mechanism
ocfs2: Convert to new freezing mechanism
xfs: Convert to new freezing code
ext4: Convert to new freezing mechanism
fs: Protect write paths by sb_start_write - sb_end_write
fs: Skip atime update on frozen filesystem
fs: Add freezing handling to mnt_want_write() / mnt_drop_write()
fs: Improve filesystem freezing handling
switch the protection of percpu_counter list to spinlock
nfsd: Push mnt_want_write() outside of i_mutex
btrfs: Push mnt_want_write() outside of i_mutex
fat: Push mnt_want_write() outside of i_mutex
...
One side effect - attempt to create a cross-device link on a read-only fs fails
with EROFS instead of EXDEV now. Makes more sense, POSIX allows, etc.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Before this patch sock_diag works for init_net only and dumps
information about sockets from all namespaces.
This patch expands sock_diag for all name-spaces.
It creates a netlink kernel socket for each netns and filters
data during dumping.
v2: filter accoding with netns in all places
remove an unused variable.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Pavel Emelyanov <xemul@parallels.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also, no need to trim on nlmsg_put() failure, nothing has been added
yet. We also want to use nlmsg_end(), nlmsg_new() and nlmsg_free().
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
As pointed out by Michael Tokarev , struct unix_iter_state is no longer
needed.
Suggested-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
/proc/net/unix has quadratic behavior, and can hold unix_table_lock for
a while if high number of unix sockets are alive. (90 ms for 200k
sockets...)
We already have a hash table, so its quite easy to use it.
Problem is unbound sockets are still hashed in a single hash slot
(unix_socket_table[UNIX_HASH_TABLE])
This patch also spreads unbound sockets to 256 hash slots, to speedup
both /proc/net/unix and unix_diag.
Time to read /proc/net/unix with 200k unix sockets :
(time dd if=/proc/net/unix of=/dev/null bs=4k)
before : 520 secs
after : 2 secs
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
read only, so change it to const.
Signed-off-by: Shan Wei <davidshan@tencent.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This results in code with less boiler plate that is a bit easier
to read.
Additionally stops us from using compatibility code in the sysctl
core, hastening the day when the compatibility code can be removed.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This makes it clearer which sysctls are relative to your current network
namespace.
This makes it a little less error prone by not exposing sysctls for the
initial network namespace in other namespaces.
This is the same way we handle all of our other network interfaces to
userspace and I can't honestly remember why we didn't do this for
sysctls right from the start.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use of "unsigned int" is preferred to bare "unsigned" in net tree.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
unix_dgram_sendmsg() currently builds linear skbs, and this can stress
page allocator with high order page allocations. When memory gets
fragmented, this can eventually fail.
We can try to use order-2 allocations for skb head (SKB_MAX_ALLOC) plus
up to 16 page fragments to lower pressure on buddy allocator.
This patch has no effect on messages of less than 16064 bytes.
(on 64bit arches with PAGE_SIZE=4096)
For bigger messages (from 16065 to 81600 bytes), this patch brings
reliability at the expense of performance penalty because of extra pages
allocations.
netperf -t DG_STREAM -T 0,2 -- -m 16064 -s 200000
->4086040 Messages / 10s
netperf -t DG_STREAM -T 0,2 -- -m 16068 -s 200000
->3901747 Messages / 10s
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In some cases the poll() implementation in a driver has to do different
things depending on the events the caller wants to poll for. An example
is when a driver needs to start a DMA engine if the caller polls for
POLLIN, but doesn't want to do that if POLLIN is not requested but instead
only POLLOUT or POLLPRI is requested. This is something that can happen
in the video4linux subsystem among others.
Unfortunately, the current epoll/poll/select implementation doesn't
provide that information reliably. The poll_table_struct does have it: it
has a key field with the event mask. But once a poll() call matches one
or more bits of that mask any following poll() calls are passed a NULL
poll_table pointer.
Also, the eventpoll implementation always left the key field at ~0 instead
of using the requested events mask.
This was changed in eventpoll.c so the key field now contains the actual
events that should be polled for as set by the caller.
The solution to the NULL poll_table pointer is to set the qproc field to
NULL in poll_table once poll() matches the events, not the poll_table
pointer itself. That way drivers can obtain the mask through a new
poll_requested_events inline.
The poll_table_struct can still be NULL since some kernel code calls it
internally (netfs_state_poll() in ./drivers/staging/pohmelfs/netfs.h). In
that case poll_requested_events() returns ~0 (i.e. all events).
Very rarely drivers might want to know whether poll_wait will actually
wait. If another earlier file descriptor in the set already matched the
events the caller wanted to wait for, then the kernel will return from the
select() call without waiting. This might be useful information in order
to avoid doing expensive work.
A new helper function poll_does_not_wait() is added that drivers can use
to detect this situation. This is now used in sock_poll_wait() in
include/net/sock.h. This was the only place in the kernel that needed
this information.
Drivers should no longer access any of the poll_table internals, but use
the poll_requested_events() and poll_does_not_wait() access functions
instead. In order to enforce that the poll_table fields are now prepended
with an underscore and a comment was added warning against using them
directly.
This required a change in unix_dgram_poll() in unix/af_unix.c which used
the key field to get the requested events. It's been replaced by a call
to poll_requested_events().
For qproc it was especially important to change its name since the
behavior of that field changes with this patch since this function pointer
can now be NULL when that wasn't possible in the past.
Any driver accessing the qproc or key fields directly will now fail to compile.
Some notes regarding the correctness of this patch: the driver's poll()
function is called with a 'struct poll_table_struct *wait' argument. This
pointer may or may not be NULL, drivers can never rely on it being one or
the other as that depends on whether or not an earlier file descriptor in
the select()'s fdset matched the requested events.
There are only three things a driver can do with the wait argument:
1) obtain the key field:
events = wait ? wait->key : ~0;
This will still work although it should be replaced with the new
poll_requested_events() function (which does exactly the same).
This will now even work better, since wait is no longer set to NULL
unnecessarily.
2) use the qproc callback. This could be deadly since qproc can now be
NULL. Renaming qproc should prevent this from happening. There are no
kernel drivers that actually access this callback directly, BTW.
3) test whether wait == NULL to determine whether poll would return without
waiting. This is no longer sufficient as the correct test is now
wait == NULL || wait->_qproc == NULL.
However, the worst that can happen here is a slight performance hit in
the case where wait != NULL and wait->_qproc == NULL. In that case the
driver will assume that poll_wait() will actually add the fd to the set
of waiting file descriptors. Of course, poll_wait() will not do that
since it tests for wait->_qproc. This will not break anything, though.
There is only one place in the whole kernel where this happens
(sock_poll_wait() in include/net/sock.h) and that code will be replaced
by a call to poll_does_not_wait() in the next patch.
Note that even if wait->_qproc != NULL drivers cannot rely on poll_wait()
actually waiting. The next file descriptor from the set might match the
event mask and thus any possible waits will never happen.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Jonathan Corbet <corbet@lwn.net>
Reviewed-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs pile 1 from Al Viro:
"This is _not_ all; in particular, Miklos' and Jan's stuff is not there
yet."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
ext4: initialization of ext4_li_mtx needs to be done earlier
debugfs-related mode_t whack-a-mole
hfsplus: add an ioctl to bless files
hfsplus: change finder_info to u32
hfsplus: initialise userflags
qnx4: new helper - try_extent()
qnx4: get rid of qnx4_bread/qnx4_getblk
take removal of PF_FORKNOEXEC to flush_old_exec()
trim includes in inode.c
um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
um: embed ->stub_pages[] into mmu_context
gadgetfs: list_for_each_safe() misuse
ocfs2: fix leaks on failure exits in module_init
ecryptfs: make register_filesystem() the last potential failure exit
ntfs: forgets to unregister sysctls on register_filesystem() failure
logfs: missing cleanup on register_filesystem() failure
jfs: mising cleanup on register_filesystem() failure
make configfs_pin_fs() return root dentry on success
configfs: configfs_create_dir() has parent dentry in dentry->d_parent
configfs: sanitize configfs_create()
...
Davem considers that the argument list of this interface is getting
out of control. This patch tries to address this issue following
his proposal:
struct netlink_dump_control c = { .dump = dump, .done = done, ... };
netlink_dump_start(..., &c);
Suggested by David S. Miller.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Piergiorgio Beruto expressed the need to fetch size of first datagram in
queue for AF_UNIX sockets and suggested a patch against SIOCINQ ioctl.
I suggested instead to implement MSG_TRUNC support as a recv() input
flag, as already done for RAW, UDP & NETLINK sockets.
len = recv(fd, &byte, 1, MSG_PEEK | MSG_TRUNC);
MSG_TRUNC asks recv() to return the real length of the packet, even when
is was longer than the passed buffer.
There is risk that a userland application used MSG_TRUNC by accident
(since it had no effect on af_unix sockets) and this might break after
this patch.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Piergiorgio Beruto <piergiorgio.beruto@gmail.com>
CC: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The same here -- we can protect the sk_peek_off manipulations with
the unix_sk->readlock mutex.
The peeking of data from a stream socket is done in the datagram style,
i.e. even if there's enough room for more data in the user buffer, only
the head skb's data is copied in there. This feature is preserved when
peeking data from a given offset -- the data is read till the nearest
skb's boundary.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The sk_peek_off manipulations are protected with the unix_sk->readlock mutex.
This mutex is enough since all we need is to syncronize setting the offset
vs reading the queue head. The latter is fully covered with the mentioned lock.
The recently added __skb_recv_datagram's offset is used to pick the skb to
read the data from.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 0884d7aa24 (AF_UNIX: Fix poll blocking problem when reading from
a stream socket) added a regression for epoll() in Edge Triggered mode
(EPOLLET)
Appropriate fix is to use skb_peek()/skb_unlink() instead of
skb_dequeue(), and only call skb_unlink() when skb is fully consumed.
This remove the need to requeue a partial skb into sk_receive_queue head
and the extra sk->sk_data_ready() calls that added the regression.
This is safe because once skb is given to sk_receive_queue, it is not
modified by a writer, and readers are serialized by u->readlock mutex.
This also reduce number of spinlock acquisition for small reads or
MSG_PEEK users so should improve overall performance.
Reported-by: Nick Mathewson <nickm@freehaven.net>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Alexey Moiseytsev <himeraster@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
igmp: Avoid zero delay when receiving odd mixture of IGMP queries
netdev: make net_device_ops const
bcm63xx: make ethtool_ops const
usbnet: make ethtool_ops const
net: Fix build with INET disabled.
net: introduce netif_addr_lock_nested() and call if when appropriate
net: correct lock name in dev_[uc/mc]_sync documentations.
net: sk_update_clone is only used in net/core/sock.c
8139cp: fix missing napi_gro_flush.
pktgen: set correct max and min in pktgen_setup_inject()
smsc911x: Unconditionally include linux/smscphy.h in smsc911x.h
asix: fix infinite loop in rx_fixup()
net: Default UDP and UNIX diag to 'n'.
r6040: fix typo in use of MCR0 register bits
net: fix sock_clone reference mismatch with tcp memcontrol
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (165 commits)
reiserfs: Properly display mount options in /proc/mounts
vfs: prevent remount read-only if pending removes
vfs: count unlinked inodes
vfs: protect remounting superblock read-only
vfs: keep list of mounts for each superblock
vfs: switch ->show_options() to struct dentry *
vfs: switch ->show_path() to struct dentry *
vfs: switch ->show_devname() to struct dentry *
vfs: switch ->show_stats to struct dentry *
switch security_path_chmod() to struct path *
vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb
vfs: trim includes a bit
switch mnt_namespace ->root to struct mount
vfs: take /proc/*/mounts and friends to fs/proc_namespace.c
vfs: opencode mntget() mnt_set_mountpoint()
vfs: spread struct mount - remaining argument of next_mnt()
vfs: move fsnotify junk to struct mount
vfs: move mnt_devname
vfs: move mnt_list to struct mount
vfs: switch pnode.h macros to struct mount *
...
While it's not too late fix the recently added RQLEN diag extension
to report rqlen and wqlen in the same way as TCP does.
I.e. for listening sockets the ack backlog length (which is the input
queue length for socket) in rqlen and the max ack backlog length in
wqlen, and what the CINQ/OUTQ ioctls do for established.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently tcp diag reports rqlen and wqlen values similar to how
the CINQ/COUTQ iotcls do. To make unix diag report these values
in the same way move the respective code into helpers.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[ Fix indentation of sock_diag*() calls. -DaveM ]
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Otherwise we leave uninitialized kernel memory in there.
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The NLA_PUT macro should accept the actual attribute length, not
the amount of elements in array :(
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Otherwise getting
| net/unix/diag.c:312:16: error: expected declaration specifiers or ‘...’ before string constant
| net/unix/diag.c:313:1: error: expected declaration specifiers or ‘...’ before string constant
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When establishing a unix connection on stream sockets the
server end receives an skb with socket in its receive queue.
Report who is waiting for these ends to be accepted for
listening sockets via NLA.
There's a lokcing issue with this -- the unix sk state lock is
required to access the peer, and it is taken under the listening
sk's queue lock. Strictly speaking the queue lock should be taken
inside the state lock, but since in this case these two sockets
are different it shouldn't lead to deadlock.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Report the peer socket inode ID as NLA. With this it's finally
possible to find out the other end of an interesting unix connection.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Actually, the socket path if it's not anonymous doesn't give
a clue to which file the socket is bound to. Even if the path
is absolute, it can be unlinked and then new socket can be
bound to it.
With this NLA it's possible to check which file a particular
socket is really bound to.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Report the sun_path when requested as NLA. With leading '\0' if
present but without the leading AF_UNIX bits.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The socket inode is used as a key for lookup. This is effectively
the only really unique ID of a unix socket, but using this for
search currently has one problem -- it is O(number of sockets) :(
Does it worth fixing this lookup or inventing some other ID for
unix sockets?
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Walk the unix sockets table and fill the core response structure,
which includes type, state and inode.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Includes basic module_init/_exit functionality, dump/get_exact stubs
and declares the basic API structures for request and response.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
poll() call may be blocked by concurrent reading from the same stream
socket.
Signed-off-by: Alexey Moiseytsev <himeraster@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 7361c36c52 (af_unix: Allow credentials to work across
user and pid namespaces) af_unix performance dropped a lot.
This is because we now take a reference on pid and cred in each write(),
and release them in read(), usually done from another process,
eventually from another cpu. This triggers false sharing.
# Events: 154K cycles
#
# Overhead Command Shared Object Symbol
# ........ ....... .................. .........................
#
10.40% hackbench [kernel.kallsyms] [k] put_pid
8.60% hackbench [kernel.kallsyms] [k] unix_stream_recvmsg
7.87% hackbench [kernel.kallsyms] [k] unix_stream_sendmsg
6.11% hackbench [kernel.kallsyms] [k] do_raw_spin_lock
4.95% hackbench [kernel.kallsyms] [k] unix_scm_to_skb
4.87% hackbench [kernel.kallsyms] [k] pid_nr_ns
4.34% hackbench [kernel.kallsyms] [k] cred_to_ucred
2.39% hackbench [kernel.kallsyms] [k] unix_destruct_scm
2.24% hackbench [kernel.kallsyms] [k] sub_preempt_count
1.75% hackbench [kernel.kallsyms] [k] fget_light
1.51% hackbench [kernel.kallsyms] [k]
__mutex_lock_interruptible_slowpath
1.42% hackbench [kernel.kallsyms] [k] sock_alloc_send_pskb
This patch includes SCM_CREDENTIALS information in a af_unix message/skb
only if requested by the sender, [man 7 unix for details how to include
ancillary data using sendmsg() system call]
Note: This might break buggy applications that expected SCM_CREDENTIAL
from an unaware write() system call, and receiver not using SO_PASSCRED
socket option.
If SOCK_PASSCRED is set on source or destination socket, we still
include credentials for mere write() syscalls.
Performance boost in hackbench : more than 50% gain on a 16 thread
machine (2 quad-core cpus, 2 threads per core)
hackbench 20 thread 2000
4.228 sec instead of 9.102 sec
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 0856a30409.
As requested by Eric Dumazet, it has various ref-counting
problems and has introduced regressions. Eric will add
a more suitable version of this performance fix.
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch series 109f6e39..7361c36c back in 2.6.36 added functionality to
allow credentials to work across pid namespaces for packets sent via
UNIX sockets. However, the atomic reference counts on pid and
credentials caused plenty of cache bouncing when there are numerous
threads of the same pid sharing a UNIX socket. This patch mitigates the
problem by eliminating extraneous reference counts on pid and
credentials on both send and receive path of UNIX sockets. I found a 2x
improvement in hackbench's threaded case.
On the receive path in unix_dgram_recvmsg, currently there is an
increment of reference count on pid and credentials in scm_set_cred.
Then there are two decrement of the reference counts. Once in scm_recv
and once when skb_free_datagram call skb->destructor function
unix_destruct_scm. One pair of increment and decrement of ref count on
pid and credentials can be eliminated from the receive path. Until we
destroy the skb, we already set a reference when we created the skb on
the send side.
On the send path, there are two increments of ref count on pid and
credentials, once in scm_send and once in unix_scm_to_skb. Then there
is a decrement of the reference counts in scm_destroy's call to
scm_destroy_cred at the end of unix_dgram_sendmsg functions. One pair
of increment and decrement of the reference counts can be removed so we
only need to increment the ref counts once.
By incorporating these changes, for hackbench running on a 4 socket
NHM-EX machine with 40 cores, the execution of hackbench on
50 groups of 20 threads sped up by factor of 2.
Hackbench command used for testing:
./hackbench 50 thread 2000
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
combination of kern_path_parent() and lookup_create(). Does *not*
expose struct nameidata to caller. Syscalls converted to that...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The %pK format specifier is designed to hide exposed kernel pointers,
specifically via /proc interfaces. Exposing these pointers provides an
easy target for kernel write vulnerabilities, since they reveal the
locations of writable structures containing easily triggerable function
pointers. The behavior of %pK depends on the kptr_restrict sysctl.
If kptr_restrict is set to 0, no deviation from the standard %p behavior
occurs. If kptr_restrict is set to 1, the default, if the current user
(intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG
(currently in the LSM tree), kernel pointers using %pK are printed as 0's.
If kptr_restrict is set to 2, kernel pointers using %pK are printed as
0's regardless of privileges. Replacing with 0's was chosen over the
default "(null)", which cannot be parsed by userland %p, which expects
"(nil)".
The supporting code for kptr_restrict and %pK are currently in the -mm
tree. This patch converts users of %p in net/ to %pK. Cases of printing
pointers to the syslog are not covered, since this would eliminate useful
information for postmortem debugging and the reading of the syslog is
already optionally protected by the dmesg_restrict sysctl.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: James Morris <jmorris@namei.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Thomas Graf <tgraf@infradead.org>
Cc: Eugene Teo <eugeneteo@kernel.org>
Cc: Kees Cook <kees.cook@canonical.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David S. Miller <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes the following oops discovered by Dan Aloni:
> Anyway, the following is the output of the Oops that I got on the
> Ubuntu kernel on which I first detected the problem
> (2.6.37-12-generic). The Oops that followed will be more useful, I
> guess.
>[ 5594.669852] BUG: unable to handle kernel NULL pointer dereference
> at (null)
> [ 5594.681606] IP: [<ffffffff81550b7b>] unix_dgram_recvmsg+0x1fb/0x420
> [ 5594.687576] PGD 2a05d067 PUD 2b951067 PMD 0
> [ 5594.693720] Oops: 0002 [#1] SMP
> [ 5594.699888] last sysfs file:
The bug was that unix domain sockets use a pseduo packet for
connecting and accept uses that psudo packet to get the socket.
In the buggy seqpacket case we were allowing unconnected
sockets to call recvmsg and try to receive the pseudo packet.
That is always wrong and as of commit 7361c36c5 the pseudo
packet had become enough different from a normal packet
that the kernel started oopsing.
Do for seqpacket_recv what was done for seqpacket_send in 2.5
and only allow it on connected seqpacket sockets.
Cc: stable@kernel.org
Tested-by: Dan Aloni <dan@aloni.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1480 commits)
bonding: enable netpoll without checking link status
xfrm: Refcount destination entry on xfrm_lookup
net: introduce rx_handler results and logic around that
bonding: get rid of IFF_SLAVE_INACTIVE netdev->priv_flag
bonding: wrap slave state work
net: get rid of multiple bond-related netdevice->priv_flags
bonding: register slave pointer for rx_handler
be2net: Bump up the version number
be2net: Copyright notice change. Update to Emulex instead of ServerEngines
e1000e: fix kconfig for crc32 dependency
netfilter ebtables: fix xt_AUDIT to work with ebtables
xen network backend driver
bonding: Improve syslog message at device creation time
bonding: Call netif_carrier_off after register_netdevice
bonding: Incorrect TX queue offset
net_sched: fix ip_tos2prio
xfrm: fix __xfrm_route_forward()
be2net: Fix UDP packet detected status in RX compl
Phonet: fix aligned-mode pipe socket buffer header reserve
netxen: support for GbE port settings
...
Fix up conflicts in drivers/staging/brcm80211/brcmsmac/wl_mac80211.c
with the staging updates.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (57 commits)
tidy the trailing symlinks traversal up
Turn resolution of trailing symlinks iterative everywhere
simplify link_path_walk() tail
Make trailing symlink resolution in path_lookupat() iterative
update nd->inode in __do_follow_link() instead of after do_follow_link()
pull handling of one pathname component into a helper
fs: allow AT_EMPTY_PATH in linkat(), limit that to CAP_DAC_READ_SEARCH
Allow passing O_PATH descriptors via SCM_RIGHTS datagrams
readlinkat(), fchownat() and fstatat() with empty relative pathnames
Allow O_PATH for symlinks
New kind of open files - "location only".
ext4: Copy fs UUID to superblock
ext3: Copy fs UUID to superblock.
vfs: Export file system uuid via /proc/<pid>/mountinfo
unistd.h: Add new syscalls numbers to asm-generic
x86: Add new syscalls for x86_64
x86: Add new syscalls for x86_32
fs: Remove i_nlink check from file system link callback
fs: Don't allow to create hardlink for deleted file
vfs: Add open by file handle support
...
Just need to make sure that AF_UNIX garbage collector won't
confuse O_PATHed socket on filesystem for real AF_UNIX opened
socket.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We latch our state using a spinlock not a r/w kind of lock.
Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
all remaining callers pass LOOKUP_PARENT to it, so
flags argument can die; renamed to kern_path_parent()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The unix_dgram_recvmsg and unix_stream_recvmsg routines in
net/af_unix.c utilize mutex_lock(&u->readlock) calls in order to
serialize read operations of multiple threads on a single socket. This
implies that, if all n threads of a process block in an AF_UNIX recv
call trying to read data from the same socket, one of these threads
will be sleeping in state TASK_INTERRUPTIBLE and all others in state
TASK_UNINTERRUPTIBLE. Provided that a particular signal is supposed to
be handled by a signal handler defined by the process and that none of
this threads is blocking the signal, the complete_signal routine in
kernel/signal.c will select the 'first' such thread it happens to
encounter when deciding which thread to notify that a signal is
supposed to be handled and if this is one of the TASK_UNINTERRUPTIBLE
threads, the signal won't be handled until the one thread not blocking
on the u->readlock mutex is woken up because some data to process has
arrived (if this ever happens). The included patch fixes this by
changing mutex_lock to mutex_lock_interruptible and handling possible
error returns in the same way interruptions are handled by the actual
receive-code.
Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add proper RCU annotations/verbs to sk_wq and wq members
Fix __sctp_write_space() sk_sleep() abuse (and sock->wq access)
Fix sunrpc sk_sleep() abuse too
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alban Crequy <alban.crequy@collabora.co.uk>
Reviewed-by: Ian Molton <ian.molton@collabora.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux Socket Filters can already be successfully attached and detached on unix
sockets with setsockopt(sockfd, SOL_SOCKET, SO_{ATTACH,DETACH}_FILTER, ...).
See: Documentation/networking/filter.txt
But the filter was never used in the unix socket code so it did not work. This
patch uses sk_filter() to filter buffers before delivery.
This short program demonstrates the problem on SOCK_DGRAM.
int main(void) {
int i, j, ret;
int sv[2];
struct pollfd fds[2];
char *message = "Hello world!";
char buffer[64];
struct sock_filter ins[32] = {{0,},};
struct sock_fprog filter;
socketpair(AF_UNIX, SOCK_DGRAM, 0, sv);
for (i = 0 ; i < 2 ; i++) {
fds[i].fd = sv[i];
fds[i].events = POLLIN;
fds[i].revents = 0;
}
for(j = 1 ; j < 13 ; j++) {
/* Set a socket filter to truncate the message */
memset(ins, 0, sizeof(ins));
ins[0].code = BPF_RET|BPF_K;
ins[0].k = j;
filter.len = 1;
filter.filter = ins;
setsockopt(sv[1], SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter));
/* send a message */
send(sv[0], message, strlen(message) + 1, 0);
/* The filter should let the message pass but truncated. */
poll(fds, 2, 0);
/* Receive the truncated message*/
ret = recv(sv[1], buffer, 64, 0);
printf("received %d bytes, expected %d\n", ret, j);
}
for (i = 0 ; i < 2 ; i++)
close(sv[i]);
return 0;
}
Signed-off-by: Alban Crequy <alban.crequy@collabora.co.uk>
Reviewed-by: Ian Molton <ian.molton@collabora.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
unix_release() can asynchornously set socket->sk to NULL, and
it does so without holding the unix_state_lock() on "other"
during stream connects.
However, the reverse mapping, sk->sk_socket, is only transitioned
to NULL under the unix_state_lock().
Therefore make the security hooks follow the reverse mapping instead
of the forward mapping.
Reported-by: Jeremy Fitzhardinge <jeremy@goop.org>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Its easy to eat all kernel memory and trigger NMI watchdog, using an
exploit program that queues unix sockets on top of others.
lkml ref : http://lkml.org/lkml/2010/11/25/8
This mechanism is used in applications, one choice we have is to have a
recursion limit.
Other limits might be needed as well (if we queue other types of files),
since the passfd mechanism is currently limited by socket receive queue
sizes only.
Add a recursion_level to unix socket, allowing up to 4 levels.
Each time we send an unix socket through sendfd mechanism, we copy its
recursion level (plus one) to receiver. This recursion level is cleared
when socket receive queue is emptied.
Reported-by: Марк Коренберг <socketpair@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vegard Nossum found a unix socket OOM was possible, posting an exploit
program.
My analysis is we can eat all LOWMEM memory before unix_gc() being
called from unix_release_sock(). Moreover, the thread blocked in
unix_gc() can consume huge amount of time to perform cleanup because of
huge working set.
One way to handle this is to have a sensible limit on unix_tot_inflight,
tested from wait_for_unix_gc() and to force a call to unix_gc() if this
limit is hit.
This solves the OOM and also reduce overall latencies, and should not
slowdown normal workloads.
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
unix_dgram_poll() is pretty expensive to check POLLOUT status, because
it has to lock the socket to get its peer, take a reference on the peer
to check its receive queue status, and queue another poll_wait on
peer_wait. This all can be avoided if the process calling
unix_dgram_poll() is not interested in POLLOUT status. It makes
unix_dgram_recvmsg() faster by not queueing irrelevant pollers in
peer_wait.
On a test program provided by Alan Crequy :
Before:
real 0m0.211s
user 0m0.000s
sys 0m0.208s
After:
real 0m0.044s
user 0m0.000s
sys 0m0.040s
Suggested-by: Davide Libenzi <davidel@xmailserver.org>
Reported-by: Alban Crequy <alban.crequy@collabora.co.uk>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alban Crequy reported a problem with connected dgram af_unix sockets and
provided a test program. epoll() would miss to send an EPOLLOUT event
when a thread unqueues a packet from the other peer, making its receive
queue not full.
This is because unix_dgram_poll() fails to call sock_poll_wait(file,
&unix_sk(other)->peer_wait, wait);
if the socket is not writeable at the time epoll_ctl(ADD) is called.
We must call sock_poll_wait(), regardless of 'writable' status, so that
epoll can be notified later of states changes.
Misc: avoids testing twice (sk->sk_shutdown & RCV_SHUTDOWN)
Reported-by: Alban Crequy <alban.crequy@collabora.co.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of wakeup all sleepers, use wake_up_interruptible_sync_poll() to
wakeup only ones interested into writing the socket.
This patch is a specialization of commit 37e5540b3c (epoll keyed
wakeups: make sockets use keyed wakeups).
On a test program provided by Alan Crequy :
Before:
real 0m3.101s
user 0m0.000s
sys 0m6.104s
After:
real 0m0.211s
user 0m0.000s
sys 0m0.208s
Reported-by: Alban Crequy <alban.crequy@collabora.co.uk>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Robin Holt tried to boot a 16TB system and found af_unix was overflowing
a 32bit value :
<quote>
We were seeing a failure which prevented boot. The kernel was incapable
of creating either a named pipe or unix domain socket. This comes down
to a common kernel function called unix_create1() which does:
atomic_inc(&unix_nr_socks);
if (atomic_read(&unix_nr_socks) > 2 * get_max_files())
goto out;
The function get_max_files() is a simple return of files_stat.max_files.
files_stat.max_files is a signed integer and is computed in
fs/file_table.c's files_init().
n = (mempages * (PAGE_SIZE / 1024)) / 10;
files_stat.max_files = n;
In our case, mempages (total_ram_pages) is approx 3,758,096,384
(0xe0000000). That leaves max_files at approximately 1,503,238,553.
This causes 2 * get_max_files() to integer overflow.
</quote>
Fix is to let /proc/sys/fs/file-nr & /proc/sys/fs/file-max use long
integers, and change af_unix to use an atomic_long_t instead of atomic_t.
get_max_files() is changed to return an unsigned long. get_nr_files() is
changed to return a long.
unix_nr_socks is changed from atomic_t to atomic_long_t, while not
strictly needed to address Robin problem.
Before patch (on a 64bit kernel) :
# echo 2147483648 >/proc/sys/fs/file-max
# cat /proc/sys/fs/file-max
-18446744071562067968
After patch:
# echo 2147483648 >/proc/sys/fs/file-max
# cat /proc/sys/fs/file-max
2147483648
# cat /proc/sys/fs/file-nr
704 0 2147483648
Reported-by: Robin Holt <holt@sgi.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David Miller <davem@davemloft.net>
Reviewed-by: Robin Holt <holt@sgi.com>
Tested-by: Robin Holt <holt@sgi.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Userspace applications can already request to receive timestamps with:
setsockopt(sockfd, SOL_SOCKET, SO_TIMESTAMP, ...)
Although setsockopt() returns zero (success), timestamps are not added to the
ancillary data. This patch fixes that on SOCK_DGRAM and SOCK_SEQPACKET Unix
sockets.
Signed-off-by: Alban Crequy <alban.crequy@collabora.co.uk>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We assumed that unix_autobind() never fails if kzalloc() succeeded.
But unix_autobind() allows only 1048576 names. If /proc/sys/fs/file-max is
larger than 1048576 (e.g. systems with more than 10GB of RAM), a local user can
consume all names using fork()/socket()/bind().
If all names are in use, those who call bind() with addr_len == sizeof(short)
or connect()/sendmsg() with setsockopt(SO_PASSCRED) will continue
while (1)
yield();
loop at unix_autobind() till a name becomes available.
This patch adds a loop counter in order to give up after 1048576 attempts.
Calling yield() for once per 256 attempts may not be sufficient when many names
are already in use, for __unix_find_socket_byname() can take long time under
such circumstance. Therefore, this patch also adds cond_resched() call.
Note that currently a local user can consume 2GB of kernel memory if the user
is allowed to create and autobind 1048576 UNIX domain sockets. We should
consider adding some restriction for autobind operation.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
No need to test twice sk->sk_shutdown & RCV_SHUTDOWN
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert a few calls from kfree_skb to consume_skb
Noticed while I was working on dropwatch that I was detecting lots of internal
skb drops in several places. While some are legitimate, several were not,
freeing skbs that were at the end of their life, rather than being discarded due
to an error. This patch converts those calls sites from using kfree_skb to
consume_skb, which quiets the in-kernel drop_monitor code from detecting them as
drops. Tested successfully by myself
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the restriction that only allows connecting to a unix domain
socket identified by unix path that is in the same network namespace.
Crossing network namespaces is always tricky and we did not support
this at first, because of a strict policy of don't mix the namespaces.
Later after Pavel proposed this we did not support this because no one
had performed the audit to make certain using unix domain sockets
across namespaces is safe.
What fundamentally makes connecting to af_unix sockets in other
namespaces is safe is that you have to have the proper permissions on
the unix domain socket inode that lives in the filesystem. If you
want strict isolation you just don't create inodes where unfriendlys
can get at them, or with permissions that allow unfriendlys to open
them. All nicely handled for us by the mount namespace and other
standard file system facilities.
I looked through unix domain sockets and they are a very controlled
environment so none of the work that goes on in dev_forward_skb to
make crossing namespaces safe appears needed, we are not loosing
controll of the skb and so do not need to set up the skb to look like
it is comming in fresh from the outside world. Further the fields in
struct unix_skb_parms should not have any problems crossing network
namespaces.
Now that we handle SCM_CREDENTIALS in a way that gives useable values
across namespaces. There does not appear to be any operational
problems with encouraging the use of unix domain sockets across
containers either.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In unix_skb_parms store pointers to struct pid and struct cred instead
of raw uid, gid, and pid values, then translate the credentials on
reception into values that are meaningful in the receiving processes
namespaces.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use struct pid and struct cred to store the peer credentials on struct
sock. This gives enough information to convert the peer credential
information to a value relative to whatever namespace the socket is in
at the time.
This removes nasty surprises when using SO_PEERCRED on socket
connetions where the processes on either side are in different pid and
user namespaces.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Worse yet, it seems that its arguments were in reverse order. Also
remove one related helper which seems hardly worth keeping.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk_callback_lock rwlock actually protects sk->sk_sleep pointer, so we
need two atomic operations (and associated dirtying) per incoming
packet.
RCU conversion is pretty much needed :
1) Add a new structure, called "struct socket_wq" to hold all fields
that will need rcu_read_lock() protection (currently: a
wait_queue_head_t and a struct fasync_struct pointer).
[Future patch will add a list anchor for wakeup coalescing]
2) Attach one of such structure to each "struct socket" created in
sock_alloc_inode().
3) Respect RCU grace period when freeing a "struct socket_wq"
4) Change sk_sleep pointer in "struct sock" by sk_wq, pointer to "struct
socket_wq"
5) Change sk_sleep() function to use new sk->sk_wq instead of
sk->sk_sleep
6) Change sk_has_sleeper() to wq_has_sleeper() that must be used inside
a rcu_read_lock() section.
7) Change all sk_has_sleeper() callers to :
- Use rcu_read_lock() instead of read_lock(&sk->sk_callback_lock)
- Use wq_has_sleeper() to eventually wakeup tasks.
- Use rcu_read_unlock() instead of read_unlock(&sk->sk_callback_lock)
8) sock_wake_async() is modified to use rcu protection as well.
9) Exceptions :
macvtap, drivers/net/tun.c, af_unix use integrated "struct socket_wq"
instead of dynamically allocated ones. They dont need rcu freeing.
Some cleanups or followups are probably needed, (possible
sk_callback_lock conversion to a spinlock for example...).
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Define a new function to return the waitqueue of a "struct sock".
static inline wait_queue_head_t *sk_sleep(struct sock *sk)
{
return sk->sk_sleep;
}
Change all read occurrences of sk_sleep by a call to this function.
Needed for a future RCU conversion. sk_sleep wont be a field directly
available.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
The lock used in unix_state_lock() is a spin_lock not reader-writer.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__net_init/__net_exit are apparently not going away, so use them
to full extent.
In some cases __net_init was removed, because it was called from
__net_exit code.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1815 commits)
mac80211: fix reorder buffer release
iwmc3200wifi: Enable wimax core through module parameter
iwmc3200wifi: Add wifi-wimax coexistence mode as a module parameter
iwmc3200wifi: Coex table command does not expect a response
iwmc3200wifi: Update wiwi priority table
iwlwifi: driver version track kernel version
iwlwifi: indicate uCode type when fail dump error/event log
iwl3945: remove duplicated event logging code
b43: fix two warnings
ipw2100: fix rebooting hang with driver loaded
cfg80211: indent regulatory messages with spaces
iwmc3200wifi: fix NULL pointer dereference in pmkid update
mac80211: Fix TX status reporting for injected data frames
ath9k: enable 2GHz band only if the device supports it
airo: Fix integer overflow warning
rt2x00: Fix padding bug on L2PAD devices.
WE: Fix set events not propagated
b43legacy: avoid PPC fault during resume
b43: avoid PPC fault during resume
tcp: fix a timewait refcnt race
...
Fix up conflicts due to sysctl cleanups (dead sysctl_check code and
CTL_UNNUMBERED removed) in
kernel/sysctl_check.c
net/ipv4/sysctl_net_ipv4.c
net/ipv6/addrconf.c
net/sctp/sysctl.c
Not including net/atm/
Compiled tested x86 allyesconfig only
Added a > 80 column line or two, which I ignored.
Existing checkpatch plaints willfully, cheerfully ignored.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that sys_sysctl is a compatiblity wrapper around /proc/sys
all sysctl strategy routines, and all ctl_name and strategy
entries in the sysctl tables are unused, and can be
revmoed.
In addition neigh_sysctl_register has been modified to no longer
take a strategy argument and it's callers have been modified not
to pass one.
Cc: "David Miller" <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Use guard DECLARE_SOCKADDR in a few more places which allow
us to catch if the structure copied back is too big.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The generic __sock_create function has a kern argument which allows the
security system to make decisions based on if a socket is being created by
the kernel or by userspace. This patch passes that flag to the
net_proto_family specific create function, so it can do the same thing.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I found a deadlock bug in UNIX domain socket, which makes able to DoS
attack against the local machine by non-root users.
How to reproduce:
1. Make a listening AF_UNIX/SOCK_STREAM socket with an abstruct
namespace(*), and shutdown(2) it.
2. Repeat connect(2)ing to the listening socket from the other sockets
until the connection backlog is full-filled.
3. connect(2) takes the CPU forever. If every core is taken, the
system hangs.
PoC code: (Run as many times as cores on SMP machines.)
int main(void)
{
int ret;
int csd;
int lsd;
struct sockaddr_un sun;
/* make an abstruct name address (*) */
memset(&sun, 0, sizeof(sun));
sun.sun_family = PF_UNIX;
sprintf(&sun.sun_path[1], "%d", getpid());
/* create the listening socket and shutdown */
lsd = socket(AF_UNIX, SOCK_STREAM, 0);
bind(lsd, (struct sockaddr *)&sun, sizeof(sun));
listen(lsd, 1);
shutdown(lsd, SHUT_RDWR);
/* connect loop */
alarm(15); /* forcely exit the loop after 15 sec */
for (;;) {
csd = socket(AF_UNIX, SOCK_STREAM, 0);
ret = connect(csd, (struct sockaddr *)&sun, sizeof(sun));
if (-1 == ret) {
perror("connect()");
break;
}
puts("Connection OK");
}
return 0;
}
(*) Make sun_path[0] = 0 to use the abstruct namespace.
If a file-based socket is used, the system doesn't deadlock because
of context switches in the file system layer.
Why this happens:
Error checks between unix_socket_connect() and unix_wait_for_peer() are
inconsistent. The former calls the latter to wait until the backlog is
processed. Despite the latter returns without doing anything when the
socket is shutdown, the former doesn't check the shutdown state and
just retries calling the latter forever.
Patch:
The patch below adds shutdown check into unix_socket_connect(), so
connect(2) to the shutdown socket will return -ECONREFUSED.
Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
Signed-off-by: Masanori Yoshida <masanori.yoshida.tv@hitachi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All usages of structure net_proto_ops should be declared const.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Kalle Olavi Niemitalo reported that:
"..., when one process calls sendmsg once to send 43804 bytes of
data and one file descriptor, and another process then calls recvmsg
three times to receive the 16032+16032+11740 bytes, each of those
recvmsg calls returns the file descriptor in the ancillary data. I
confirmed this with strace. The behaviour differs from Linux
2.6.26, where reportedly only one of those recvmsg calls (I think
the first one) returned the file descriptor."
This bug was introduced by a patch from me titled "net: unix: fix inflight
counting bug in garbage collector", commit 6209344f5.
And the reason is, quoting Kalle:
"Before your patch, unix_attach_fds() would set scm->fp = NULL, so
that if the loop in unix_stream_sendmsg() ran multiple iterations,
it could not call unix_attach_fds() again. But now,
unix_attach_fds() leaves scm->fp unchanged, and I think this causes
it to be called multiple times and duplicate the same file
descriptors to each struct sk_buff."
Fix this by introducing a flag that is cleared at the start and set
when the fds attached to the first buffer. The resulting code should
work equivalently to the one on 2.6.26.
Reported-by: Kalle Olavi Niemitalo <kon@iki.fi>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adding memory barrier after the poll_wait function, paired with
receive callbacks. Adding fuctions sock_poll_wait and sk_has_sleeper
to wrap the memory barrier.
Without the memory barrier, following race can happen.
The race fires, when following code paths meet, and the tp->rcv_nxt
and __add_wait_queue updates stay in CPU caches.
CPU1 CPU2
sys_select receive packet
... ...
__add_wait_queue update tp->rcv_nxt
... ...
tp->rcv_nxt check sock_def_readable
... {
schedule ...
if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
wake_up_interruptible(sk->sk_sleep)
...
}
If there was no cache the code would work ok, since the wait_queue and
rcv_nxt are opposit to each other.
Meaning that once tp->rcv_nxt is updated by CPU2, the CPU1 either already
passed the tp->rcv_nxt check and sleeps, or will get the new value for
tp->rcv_nxt and will return with new data mask.
In both cases the process (CPU1) is being added to the wait queue, so the
waitqueue_active (CPU2) call cannot miss and will wake up CPU1.
The bad case is when the __add_wait_queue changes done by CPU1 stay in its
cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 will then
endup calling schedule and sleep forever if there are no more data on the
socket.
Calls to poll_wait in following modules were ommited:
net/bluetooth/af_bluetooth.c
net/irda/af_irda.c
net/irda/irnet/irnet_ppp.c
net/mac80211/rc80211_pid_debugfs.c
net/phonet/socket.c
net/rds/af_rds.c
net/rfkill/core.c
net/sunrpc/cache.c
net/sunrpc/rpc_pipe.c
net/tipc/socket.c
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 2b85a34e91
(net: No more expensive sock_hold()/sock_put() on each tx)
changed initial sk_wmem_alloc value.
We need to take into account this offset when reporting
sk_wmem_alloc to user, in PROC_FS files or various
ioctls (SIOCOUTQ/TIOCOUTQ)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove some pointless conditionals before kfree_skb().
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add new LSM hooks for path-based checks. Call them on directory-modifying
operations at the points where we still know the vfsmount involved.
Signed-off-by: Kentaro Takeda <takedakn@nttdata.co.jp>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Toshiharu Harada <haradats@nttdata.co.jp>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1429 commits)
net: Allow dependancies of FDDI & Tokenring to be modular.
igb: Fix build warning when DCA is disabled.
net: Fix warning fallout from recent NAPI interface changes.
gro: Fix potential use after free
sfc: If AN is enabled, always read speed/duplex from the AN advertising bits
sfc: When disabling the NIC, close the device rather than unregistering it
sfc: SFT9001: Add cable diagnostics
sfc: Add support for multiple PHY self-tests
sfc: Merge top-level functions for self-tests
sfc: Clean up PHY mode management in loopback self-test
sfc: Fix unreliable link detection in some loopback modes
sfc: Generate unique names for per-NIC workqueues
802.3ad: use standard ethhdr instead of ad_header
802.3ad: generalize out mac address initializer
802.3ad: initialize ports LACPDU from const initializer
802.3ad: remove typedef around ad_system
802.3ad: turn ports is_individual into a bool
802.3ad: turn ports is_enabled into a bool
802.3ad: make ntt bool
ixgbe: Fix set_ringparam in ixgbe to use the same memory pools.
...
Fixed trivial IPv4/6 address printing conflicts in fs/cifs/connect.c due
to the conversion to %pI (in this networking merge) and the addition of
doing IPv6 addresses (from the earlier merge of CIFS).
Conflicts:
fs/nfsd/nfs4recover.c
Manually fixed above to use new creds API functions, e.g.
nfs4_save_creds().
Signed-off-by: James Morris <jmorris@namei.org>
This is an implementation of David Miller's suggested fix in:
https://bugzilla.redhat.com/show_bug.cgi?id=470201
It has been updated to use wait_event() instead of
wait_event_interruptible().
Paraphrasing the description from the above report, it makes sendmsg()
block while UNIX garbage collection is in progress. This avoids a
situation where child processes continue to queue new FDs over a
AF_UNIX socket to a parent which is in the exit path and running
garbage collection on these FDs. This contention can result in soft
lockups and oom-killing of unrelated processes.
Signed-off-by: dann frazier <dannf@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of using one atomic_t per protocol, use a percpu_counter
for "sockets_allocated", to reduce cache line contention on
heavy duty network servers.
Note : We revert commit (248969ae31
net: af_unix can make unix_nr_socks visbile in /proc),
since it is not anymore used after sock_prot_inuse_add() addition
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The rule of calling sock_prot_inuse_add() is that BHs must
be disabled. Some new calls were added where this was not
true and this tiggers warnings as reported by Ilpo.
Fix this by adding explicit BH disabling around those call sites,
or moving sock_prot_inuse_add() call inside an existing BH disabled
section.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The rule of calling sock_prot_inuse_add() is that BHs must
be disabled. Some new calls were added where this was not
true and this tiggers warnings as reported by Ilpo.
Fix this by adding explicit BH disabling around those call sites.
Signed-off-by: David S. Miller <davem@davemloft.net>
As spotted by Joe Perches, we should use KERN_INFO in unix_sock_destructor()
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The first argument to csum_partial is const void *
casts to char/u8 * are not necessary
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is a preparation to namespace conversion of /proc/net/protocols
In order to have relevant information for UNIX protocol, we should use
sock_prot_inuse_add() to update a (percpu and pernamespace) counter of
inuse sockets.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, /proc/net/protocols displays socket counts only for TCP/TCPv6
protocols
We can provide unix_nr_socks for free here, this counter being
already maintained in af_unix
Before patch :
# grep UNIX /proc/net/protocols
UNIX 428 -1 -1 NI 0 yes kernel
After patch :
# grep UNIX /proc/net/protocols
UNIX 428 98 -1 NI 0 yes kernel
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a pure cleanup of net/unix/af_unix.c to meet current code
style standards
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
security/keys/internal.h
security/keys/process_keys.c
security/keys/request_key.c
Fixed conflicts above by using the non 'tsk' versions.
Signed-off-by: James Morris <jmorris@namei.org>
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.
Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: netdev@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
Previously I assumed that the receive queues of candidates don't
change during the GC. This is only half true, nothing can be received
from the queues (see comment in unix_gc()), but buffers could be added
through the other half of the socket pair, which may still have file
descriptors referring to it.
This can result in inc_inflight_move_tail() erronously increasing the
"inflight" counter for a unix socket for which dec_inflight() wasn't
previously called. This in turn can trigger the "BUG_ON(total_refs <
inflight_refs)" in a later garbage collection run.
Fix this by only manipulating the "inflight" counter for sockets which
are candidates themselves. Duplicating the file references in
unix_attach_fds() is also needed to prevent a socket becoming a
candidate for GC while the skb that contains it is not yet queued.
Reported-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I want to compile out proc_* and sysctl_* handlers totally and
stub them to NULL depending on config options, however usage of &
will prevent this, since taking adress of NULL pointer will break
compilation.
So, drop & in front of every ->proc_handler and every ->strategy
handler, it was never needed in fact.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
clean up net/unix/af_unix.c garbage.c sysctl_net_unix.c
Signed-off-by: Jianjun Kong <jianjun@zeuux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
fix problem of return value
net/unix/af_unix.c: unix_net_init()
when error appears, it should return 'error', not always return 0.
Signed-off-by: Jianjun Kong <jianjun@zeuux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Clean up the various different email addresses of mine listed in the code
to a single current and valid address. As Dave says his network merges
for 2.6.28 are now done this seems a good point to send them in where
they won't risk disrupting real changes.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (39 commits)
[PATCH] fix RLIM_NOFILE handling
[PATCH] get rid of corner case in dup3() entirely
[PATCH] remove remaining namei_{32,64}.h crap
[PATCH] get rid of indirect users of namei.h
[PATCH] get rid of __user_path_lookup_open
[PATCH] f_count may wrap around
[PATCH] dup3 fix
[PATCH] don't pass nameidata to __ncp_lookup_validate()
[PATCH] don't pass nameidata to gfs2_lookupi()
[PATCH] new (local) helper: user_path_parent()
[PATCH] sanitize __user_walk_fd() et.al.
[PATCH] preparation to __user_walk_fd cleanup
[PATCH] kill nameidata passing to permission(), rename to inode_permission()
[PATCH] take noexec checks to very few callers that care
Re: [PATCH 3/6] vfs: open_exec cleanup
[patch 4/4] vfs: immutable inode checking cleanup
[patch 3/4] fat: dont call notify_change
[patch 2/4] vfs: utimes cleanup
[patch 1/4] vfs: utimes: move owner check into inode_change_ok()
[PATCH] vfs: use kstrdup() and check failing allocation
...
make it atomic_long_t; while we are at it, get rid of useless checks in affs,
hfs and hpfs - ->open() always has it equal to 1, ->release() - to 0.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Removes legacy reinvent-the-wheel type thing. The generic
machinery integrates much better to automated debugging aids
such as kerneloops.org (and others), and is unambiguous due to
better naming. Non-intuively BUG_TRAP() is actually equal to
WARN_ON() rather than BUG_ON() though some might actually be
promoted to BUG_ON() but I left that to future.
I could make at least one BUILD_BUG_ON conversion.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
For n:1 'datagram connections' (eg /dev/log), the unix_dgram_sendmsg
routine implements a form of receiver-imposed flow control by
comparing the length of the receive queue of the 'peer socket' with
the max_ack_backlog value stored in the corresponding sock structure,
either blocking the thread which caused the send-routine to be called
or returning EAGAIN. This routine is used by both SOCK_DGRAM and
SOCK_SEQPACKET sockets. The poll-implementation for these socket types
is datagram_poll from core/datagram.c. A socket is deemed to be
writeable by this routine when the memory presently consumed by
datagrams owned by it is less than the configured socket send buffer
size. This is always wrong for PF_UNIX non-stream sockets connected to
server sockets dealing with (potentially) multiple clients if the
abovementioned receive queue is currently considered to be full.
'poll' will then return, indicating that the socket is writeable, but
a subsequent write result in EAGAIN, effectively causing an (usual)
application to 'poll for writeability by repeated send request with
O_NONBLOCK set' until it has consumed its time quantum.
The change below uses a suitably modified variant of the datagram_poll
routines for both type of PF_UNIX sockets, which tests if the
recv-queue of the peer a socket is connected to is presently
considered to be 'full' as part of the 'is this socket
writeable'-checking code. The socket being polled is additionally
put onto the peer_wait wait queue associated with its peer, because the
unix_dgram_recvmsg routine does a wake up on this queue after a
datagram was received and the 'other wakeup call' is done implicitly
as part of skb destruction, meaning, a process blocked in poll
because of a full peer receive queue could otherwise sleep forever
if no datagram owned by its socket was already sitting on this queue.
Among this change is a small (inline) helper routine named
'unix_recvq_full', which consolidates the actual testing code (in three
different places) into a single location.
Signed-off-by: Rainer Weikusat <rweikusat@mssgmbh.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The unix_dgram_sendmsg routine implements a (somewhat crude)
form of receiver-imposed flow control by comparing the length of the
receive queue of the 'peer socket' with the max_ack_backlog value
stored in the corresponding sock structure, either blocking
the thread which caused the send-routine to be called or returning
EAGAIN. This routine is used by both SOCK_DGRAM and SOCK_SEQPACKET
sockets. The poll-implementation for these socket types is
datagram_poll from core/datagram.c. A socket is deemed to be writeable
by this routine when the memory presently consumed by datagrams
owned by it is less than the configured socket send buffer size. This
is always wrong for connected PF_UNIX non-stream sockets when the
abovementioned receive queue is currently considered to be full.
'poll' will then return, indicating that the socket is writeable, but
a subsequent write result in EAGAIN, effectively causing an
(usual) application to 'poll for writeability by repeated send request
with O_NONBLOCK set' until it has consumed its time quantum.
The change below uses a suitably modified variant of the datagram_poll
routines for both type of PF_UNIX sockets, which tests if the
recv-queue of the peer a socket is connected to is presently
considered to be 'full' as part of the 'is this socket
writeable'-checking code. The socket being polled is additionally
put onto the peer_wait wait queue associated with its peer, because the
unix_dgram_sendmsg routine does a wake up on this queue after a
datagram was received and the 'other wakeup call' is done implicitly
as part of skb destruction, meaning, a process blocked in poll
because of a full peer receive queue could otherwise sleep forever
if no datagram owned by its socket was already sitting on this queue.
Among this change is a small (inline) helper routine named
'unix_recvq_full', which consolidates the actual testing code (in three
different places) into a single location.
Signed-off-by: Rainer Weikusat <rweikusat@mssgmbh.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes CVS keywords that weren't updated for a long time
from comments.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (22 commits)
tun: Multicast handling in tun_chr_ioctl() needs proper locking.
[NET]: Fix heavy stack usage in seq_file output routines.
[AF_UNIX] Initialise UNIX sockets before general device initcalls
[RTNETLINK]: Fix bogus ASSERT_RTNL warning
iwlwifi: Fix built-in compilation of iwlcore (part 2)
tun: Fix minor race in TUNSETLINK ioctl handling.
ppp_generic: use stats from net_device structure
iwlwifi: Don't unlock priv->mutex if it isn't locked
wireless: rndis_wlan: modparam_workaround_interval is never below 0.
prism54: prism54_get_encode() test below 0 on unsigned index
mac80211: update mesh EID values
b43: Workaround DMA quirks
mac80211: fix use before check of Qdisc length
net/mac80211/rx.c: fix off-by-one
mac80211: Fix race between ieee80211_rx_bss_put and lookup routines.
ath5k: Fix radio identification on AR5424/2424
ssb: Fix all-ones boardflags
b43: Add more btcoexist workarounds
b43: Fix HostFlags data types
b43: Workaround invalid bluetooth settings
...
When drivers call request_module(), it tries to do something with UNIX
sockets and triggers a 'runaway loop modprobe net-pf-1' warning. Avoid
this by initialising AF_UNIX support earlier.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This takes care of all of the direct callers of vfs_mknod().
Since a few of these cases also handle normal file creation
as well, this also covers some calls to vfs_create().
So that we don't have to make three mnt_want/drop_write()
calls inside of the switch statement, we move some of its
logic outside of the switch and into a helper function
suggested by Christoph.
This also encapsulates a fix for mknod(S_IFREG) that Miklos
found.
[AV: merged mkdir handling, added missing nfsd pieces]
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Introduce an inline net_eq() to compare two namespaces.
Without CONFIG_NET_NS, since no namespace other than &init_net
exists, it is always 1.
We do not need to convert 1) inline vs inline and
2) inline vs &init_net comparisons.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Without CONFIG_NET_NS, no namespace other than &init_net exists,
no need to store net in seq_net_private.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Introduce per-sock inlines: sock_net(), sock_net_set()
and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* Add path_put() functions for releasing a reference to the dentry and
vfsmount of a struct path in the right order
* Switch from path_release(nd) to path_put(&nd->path)
* Rename dput_path() to path_put_conditional()
[akpm@linux-foundation.org: fix cifs]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.
Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
<dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
struct path in every place where the stack can be traversed
- it reduces the overall code size:
without patch series:
text data bss dec hex filename
5321639 858418 715768 6895825 6938d1 vmlinux
with patch series:
text data bss dec hex filename
5320026 858418 715768 6894212 693284 vmlinux
This patch:
Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add __acquires() and __releases() annotations to suppress some sparse
warnings.
example of warnings :
net/ipv4/udp.c:1555:14: warning: context imbalance in 'udp_seq_start' - wrong
count at exit
net/ipv4/udp.c:1571:13: warning: context imbalance in 'udp_seq_stop' -
unexpected unlock
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Recently David Miller and Herbert Xu pointed out that struct net becomes
overbloated and un-maintainable. There are two solutions:
- provide a pointer to a network subsystem definition from struct net.
This costs an additional dereferrence
- place sub-system definition into the structure itself. This will speedup
run-time access at the cost of recompilation time
The second approach looks better for us. Other sub-systems will follow.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the core.
* add the ctl_table_header on the struct net;
* make the unix_sysctl_register and _unregister clone the table;
* moves calls to them into per-net init and exit callbacks;
* move the .data pointer in the proper place.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unlike previous ones, this patch is useful by its own,
as it decreases the vmlinux size :)
But it will be used later, when the per-namespace sysctl
is added.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This will make all the sub-namespaces always use the
default value (10) and leave the tuning via sysctl
to the init namespace only.
Per-namespace tuning is coming.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the struct net * argument to both of them to use in
the future. Also make the register one return an error code.
It is useless right now, but will make the future patches
much simpler.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The sock_wake_async() performs a bit different actions
depending on "how" argument. Unfortunately this argument
ony has numerical magic values.
I propose to give names to their constants to help people
reading this function callers understand what's going on
without looking into this function all the time.
I suppose this is 2.6.25 material, but if it's not (or the
naming seems poor/bad/awful), I can rework it against the
current net-2.6 tree.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The first_unix_socket() and next_unix_sockets() are now used
in proc file and in forall_unix_socets macro only.
The forall_unix_sockets is not used in this file at all so
remove it. After this move the helpers to where they really
belong, i.e. closer to proc code under the #ifdef CONFIG_PROC_FS
option.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Because of the global nature of garbage collection, and because of the
cost of per namespace hash tables unix_socket_table has been kept
global. With a filter added on lookups so we don't see sockets from
the wrong namespace.
Currently I don't fold the namesapce into the hash so multiple
namespaces using the same socket name will be guaranteed a hash
collision.
Changes from v1:
- fixed unix_seq_open
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I am not absolutely sure whether this actually is a bug (as in: I've got
no clue what the standards say or what other implementations do), but at
least I was pretty surprised when I noticed that a recv() on a
non-blocking unix domain socket of type SOCK_SEQPACKET (which is connection
oriented, after all) where the remote end has closed the connection
returned -1 (EAGAIN) rather than 0 to indicate end of file.
This is a test case:
| #include <sys/types.h>
| #include <unistd.h>
| #include <sys/socket.h>
| #include <sys/un.h>
| #include <fcntl.h>
| #include <string.h>
| #include <stdlib.h>
|
| int main(){
| int sock;
| struct sockaddr_un addr;
| char buf[4096];
| int pfds[2];
|
| pipe(pfds);
| sock=socket(PF_UNIX,SOCK_SEQPACKET,0);
| addr.sun_family=AF_UNIX;
| strcpy(addr.sun_path,"/tmp/foobar_testsock");
| bind(sock,(struct sockaddr *)&addr,sizeof(addr));
| listen(sock,1);
| if(fork()){
| close(sock);
| sock=socket(PF_UNIX,SOCK_SEQPACKET,0);
| connect(sock,(struct sockaddr *)&addr,sizeof(addr));
| fcntl(sock,F_SETFL,fcntl(sock,F_GETFL)|O_NONBLOCK);
| close(pfds[1]);
| read(pfds[0],buf,sizeof(buf));
| recv(sock,buf,sizeof(buf),0); // <-- this one
| }else accept(sock,NULL,NULL);
| exit(0);
| }
If you try it, make sure /tmp/foobar_testsock doesn't exist.
The marked recv() returns -1 (EAGAIN) on 2.6.23.9. Below you find a
patch that fixes that.
Signed-off-by: Florian Zumbiehl <florz@florz.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The unix_nr_socks value is limited with the 2 * get_max_files() value,
as seen from the unix_create1(). However, the check and the actual
increment are separated with the GFP_KERNEL allocation, so this limit
can be exceeded under a memory pressure - task may go to sleep freeing
the pages and some other task will be allowed to allocate a new sock
and so on and so forth.
So make the increment before the check (similar thing is done in the
sock_kmalloc) and go to kmalloc after this.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The scan_inflight() routine scans through the unix sockets and calls
some passed callback. The fact is that all these callbacks work with
the unix_sock objects, not the sock ones, so make this conversion in
the scan_inflight() before calling the callbacks.
This removes one unneeded variable from the inc_inflight_move_tail().
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This counter is _always_ modified under the unix_gc_lock spinlock,
so its atomicity can be provided w/o additional efforts.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Finally, the zero_it argument can be completely removed from
the callers and from the function prototype.
Besides, fix the checkpatch.pl warnings about using the
assignments inside if-s.
This patch is rather big, and it is a part of the previous one.
I splitted it wishing to make the patches more readable. Hope
this particular split helped.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the largest patch in the set. Make all (I hope) the places where
the pid is shown to or get from user operate on the virtual pids.
The idea is:
- all in-kernel data structures must store either struct pid itself
or the pid's global nr, obtained with pid_nr() call;
- when seeking the task from kernel code with the stored id one
should use find_task_by_pid() call that works with global pids;
- when showing pid's numerical value to the user the virtual one
should be used, but however when one shows task's pid outside this
task's namespace the global one is to be used;
- when getting the pid from userspace one need to consider this as
the virtual one and use appropriate task/pid-searching functions.
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: nuther build fix]
[akpm@linux-foundation.org: yet nuther build fix]
[akpm@linux-foundation.org: remove unneeded casts]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
make sync wakeups affine for cache-cold tasks: if a cache-cold task
is woken up by a sync wakeup then use the opportunity to migrate it
straight away. (the two tasks are 'related' because they communicate)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This concerns the ipv4 and ipv6 code mostly, but also the netlink
and unix sockets.
The netlink code is an example of how to use the __seq_open_private()
call - it saves the net namespace on this private.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch passes in the namespace a new socket should be created in
and has the socket code do the appropriate reference counting. By
virtue of this all socket create methods are touched. In addition
the socket create methods are modified so that they will fail if
you attempt to create a socket in a non-default network namespace.
Failing if we attempt to create a socket outside of the default
network namespace ensures that as we incrementally make the network stack
network namespace aware we will not export functionality that someone
has not audited and made certain is network namespace safe.
Allowing us to partially enable network namespaces before all of the
exotic protocols are supported.
Any protocol layers I have missed will fail to compile because I now
pass an extra parameter into the socket creation code.
[ Integrated AF_IUCV build fixes from Andrew Morton... -DaveM ]
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes /proc/net per network namespace. It modifies the global
variables proc_net and proc_net_stat to be per network namespace.
The proc_net file helpers are modified to take a network namespace argument,
and all of their callers are fixed to pass &init_net for that argument.
This ensures that all of the /proc/net files are only visible and
usable in the initial network namespace until the code behind them
has been updated to be handle multiple network namespaces.
Making /proc/net per namespace is necessary as at least some files
in /proc/net depend upon the set of network devices which is per
network namespace, and even more files in /proc/net have contents
that are relevant to a single network namespace.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The following code can now become static:
- struct unix_socket_table
- unix_table_lock
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Throw out the old mark & sweep garbage collector and put in a
refcounting cycle detecting one.
The old one had a race with recvmsg, that resulted in false positives
and hence data loss. The old algorithm operated on all unix sockets
in the system, so any additional locking would have meant performance
problems for all users of these.
The new algorithm instead only operates on "in flight" sockets, which
are very rare, and the additional locking for these doesn't negatively
impact the vast majority of users.
In fact it's probable, that there weren't *any* heavy senders of
sockets over sockets, otherwise the above race would have been
discovered long ago.
The patch works OK with the app that exposed the race with the old
code. The garbage collection has also been verified to work in a few
simple cases.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make all initialized struct seq_operations in net/ const
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
A recv() on an AF_UNIX, SOCK_STREAM socket can race with a
send()+close() on the peer, causing recv() to return zero, even though
the sent data should be received.
This happens if the send() and the close() is performed between
skb_dequeue() and checking sk->sk_shutdown in unix_stream_recvmsg():
process A skb_dequeue() returns NULL, there's no data in the socket queue
process B new data is inserted onto the queue by unix_stream_sendmsg()
process B sk->sk_shutdown is set to SHUTDOWN_MASK by unix_release_sock()
process A sk->sk_shutdown is checked, unix_release_sock() returns zero
I'm surprised nobody noticed this, it's not hard to trigger. Maybe
it's just (un)luck with the timing.
It's possible to work around this bug in userspace, by retrying the
recv() once in case of a zero return value.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based upon an excellent bug report and initial patch by
Frederik Deweerdt.
The UNIX datagram connect code blindly dereferences other->sk_socket
via the call down to the security_unix_may_send() function.
Without locking 'other' that pointer can go NULL via unix_release_sock()
which does sock_orphan() which also marks the socket SOCK_DEAD.
So we have to lock both 'sk' and 'other' yet avoid all kinds of
potential deadlocks (connect to self is OK for datagram sockets and it
is possible for two datagram sockets to perform a simultaneous connect
to each other). So what we do is have a "double lock" function similar
to how we handle this situation in other areas of the kernel. We take
the lock of the socket pointer with the smallest address first in
order to avoid ABBA style deadlocks.
Once we have them both locked, we check to see if SOCK_DEAD is set
for 'other' and if so, drop everything and retry the lookup.
Signed-off-by: David S. Miller <davem@davemloft.net>
The unix_state_*() locking macros imply that there is some
rwlock kind of thing going on, but the implementation is
actually a spinlock which makes the code more confusing than
it needs to be.
So use plain unix_state_lock and unix_state_unlock.
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For the common, open coded 'skb->h.raw = skb->data' operation, so that we can
later turn skb->h.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.
This one touches just the most simple cases:
skb->h.raw = skb->data;
skb->h.raw = {skb_push|[__]skb_pull}()
The next ones will handle the slightly more "complex" cases.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
