sk->sk_receive_queue is protected by skb queue lock, but for KCM
sockets its RX path takes mux->rx_lock to protect more than just
skb queue. However, kcm_recvmsg() still only grabs the skb queue
lock, so race conditions still exist.
We can teach kcm_recvmsg() to grab mux->rx_lock too but this would
introduce a potential performance regression as struct kcm_mux can
be shared by multiple KCM sockets.
So we have to enforce skb queue lock in requeue_rx_msgs() and handle
skb peek case carefully in kcm_wait_data(). Fortunately,
skb_recv_datagram() already handles it nicely and is widely used by
other sockets, we can just switch to skb_recv_datagram() after
getting rid of the unnecessary sock lock in kcm_recvmsg() and
kcm_splice_read(). Side note: SOCK_DONE is not used by KCM sockets,
so it is safe to get rid of this check too.
I ran the original syzbot reproducer for 30 min without seeing any
issue.
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Reported-by: syzbot+278279efdd2730dd14bf@syzkaller.appspotmail.com
Reported-by: shaozhengchao <shaozhengchao@huawei.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Link: https://lore.kernel.org/r/20221114005119.597905-1-xiyou.wangcong@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Similar to changes done in TCP in blamed commit.
We should not sense pfmemalloc status in sendpage() methods.
Fixes: 3261400639 ("tcp: TX zerocopy should not sense pfmemalloc status")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20221027040637.1107703-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
kcm->rx_psock can be read locklessly in kcm_rfree().
Annotate the read and writes accordingly.
We do the same for kcm->rx_wait in the following patch.
syzbot reported:
BUG: KCSAN: data-race in kcm_rfree / unreserve_rx_kcm
write to 0xffff888123d827b8 of 8 bytes by task 2758 on cpu 1:
unreserve_rx_kcm+0x72/0x1f0 net/kcm/kcmsock.c:313
kcm_rcv_strparser+0x2b5/0x3a0 net/kcm/kcmsock.c:373
__strp_recv+0x64c/0xd20 net/strparser/strparser.c:301
strp_recv+0x6d/0x80 net/strparser/strparser.c:335
tcp_read_sock+0x13e/0x5a0 net/ipv4/tcp.c:1703
strp_read_sock net/strparser/strparser.c:358 [inline]
do_strp_work net/strparser/strparser.c:406 [inline]
strp_work+0xe8/0x180 net/strparser/strparser.c:415
process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
worker_thread+0x618/0xa70 kernel/workqueue.c:2436
kthread+0x1a9/0x1e0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
read to 0xffff888123d827b8 of 8 bytes by task 5859 on cpu 0:
kcm_rfree+0x14c/0x220 net/kcm/kcmsock.c:181
skb_release_head_state+0x8e/0x160 net/core/skbuff.c:841
skb_release_all net/core/skbuff.c:852 [inline]
__kfree_skb net/core/skbuff.c:868 [inline]
kfree_skb_reason+0x5c/0x260 net/core/skbuff.c:891
kfree_skb include/linux/skbuff.h:1216 [inline]
kcm_recvmsg+0x226/0x2b0 net/kcm/kcmsock.c:1161
____sys_recvmsg+0x16c/0x2e0
___sys_recvmsg net/socket.c:2743 [inline]
do_recvmmsg+0x2f1/0x710 net/socket.c:2837
__sys_recvmmsg net/socket.c:2916 [inline]
__do_sys_recvmmsg net/socket.c:2939 [inline]
__se_sys_recvmmsg net/socket.c:2932 [inline]
__x64_sys_recvmmsg+0xde/0x160 net/socket.c:2932
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
value changed: 0xffff88812971ce00 -> 0x0000000000000000
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5859 Comm: syz-executor.3 Not tainted 6.0.0-syzkaller-12189-g19d17ab7c68b-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
strp_init() is called just a few lines above this csk->sk_user_data
check, it also initializes strp->work etc., therefore, it is
unnecessary to call strp_done() to cancel the freshly initialized
work.
And if sk_user_data is already used by KCM, psock->strp should not be
touched, particularly strp->work state, so we need to move strp_init()
after the csk->sk_user_data check.
This also makes a lockdep warning reported by syzbot go away.
Reported-and-tested-by: syzbot+9fc084a4348493ef65d2@syzkaller.appspotmail.com
Reported-by: syzbot+e696806ef96cdd2d87cd@syzkaller.appspotmail.com
Fixes: e557124023 ("kcm: Check if sk_user_data already set in kcm_attach")
Fixes: dff8baa261 ("kcm: Call strp_stop before strp_done in kcm_attach")
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Link: https://lore.kernel.org/r/20220827181314.193710-1-xiyou.wangcong@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.
There's a lot of missing includes this was masking. Primarily
in networking tho, this time.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org
This patch introduces a function wrapper to call the sk_error_report
callback. That will prepare to add additional handling whenever
sk_error_report is called, for example to trace socket errors.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In commit c47cc30499 ("net: kcm: fix memory leak in kcm_sendmsg")
I misunderstood the root case of the memory leak and came up with
completely broken fix.
So, simply revert this commit to avoid GPF reported by
syzbot.
Im so sorry for this situation.
Fixes: c47cc30499 ("net: kcm: fix memory leak in kcm_sendmsg")
Reported-by: syzbot+65badd5e74ec62cb67dc@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Syzbot reported memory leak in kcm_sendmsg()[1].
The problem was in non-freed frag_list in case of error.
In the while loop:
if (head == skb)
skb_shinfo(head)->frag_list = tskb;
else
skb->next = tskb;
frag_list filled with skbs, but nothing was freeing them.
backtrace:
[<0000000094c02615>] __alloc_skb+0x5e/0x250 net/core/skbuff.c:198
[<00000000e5386cbd>] alloc_skb include/linux/skbuff.h:1083 [inline]
[<00000000e5386cbd>] kcm_sendmsg+0x3b6/0xa50 net/kcm/kcmsock.c:967 [1]
[<00000000f1613a8a>] sock_sendmsg_nosec net/socket.c:652 [inline]
[<00000000f1613a8a>] sock_sendmsg+0x4c/0x60 net/socket.c:672
Reported-and-tested-by: syzbot+b039f5699bd82e1fb011@syzkaller.appspotmail.com
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
s/synchonization/synchronization/
s/aready/already/
Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for expanded zerocopy (TX and RX), move
the zerocopy related bits out of tx_flags into their own
flag word.
Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The function sockfd_lookup uses fget on the value that is stored in
the file field of the returned structure, so fput should ultimately be
applied to this value. This can be done directly, but it seems better
to use the specific macro sockfd_put, which does the same thing.
Perform a source code refactoring by using the following semantic patch.
// <smpl>
@@
expression s;
@@
s = sockfd_lookup(...)
...
+ sockfd_put(s);
- fput(s->file);
// </smpl>
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rework the remaining setsockopt code to pass a sockptr_t instead of a
plain user pointer. This removes the last remaining set_fs(KERNEL_DS)
outside of architecture specific code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154]
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
All of these cases are strictly of the form:
preempt_disable();
BPF_PROG_RUN(...);
preempt_enable();
Replace this with bpf_prog_run_pin_on_cpu() which wraps BPF_PROG_RUN()
with:
migrate_disable();
BPF_PROG_RUN(...);
migrate_enable();
On non RT enabled kernels this maps to preempt_disable/enable() and on RT
enabled kernels this solely prevents migration, which is sufficient as
there is no requirement to prevent reentrancy to any BPF program from a
preempting task. The only requirement is that the program stays on the same
CPU.
Therefore, this is a trivially correct transformation.
The seccomp loop does not need protection over the loop. It only needs
protection per BPF filter program
[ tglx: Converted to bpf_prog_run_pin_on_cpu() ]
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.691493094@linutronix.de
Instead of invoking struct bpf_prog::bpf_func directly, use the
BPF_PROG_RUN macro.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Use accessor functions for skb fragment's page_offset instead
of direct references, in preparation for bvec conversion.
Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for unifying the skb_frag and bio_vec, use the fine
accessors which already exist and use skb_frag_t instead of
struct skb_frag_struct.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When kcm is loaded while many processes try to create a KCM socket, a
crash occurs:
BUG: unable to handle kernel NULL pointer dereference at 000000000000000e
IP: mutex_lock+0x27/0x40 kernel/locking/mutex.c:240
PGD 8000000016ef2067 P4D 8000000016ef2067 PUD 3d6e9067 PMD 0
Oops: 0002 [#1] SMP KASAN PTI
CPU: 0 PID: 7005 Comm: syz-executor.5 Not tainted 4.12.14-396-default #1 SLE15-SP1 (unreleased)
RIP: 0010:mutex_lock+0x27/0x40 kernel/locking/mutex.c:240
RSP: 0018:ffff88000d487a00 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 000000000000000e RCX: 1ffff100082b0719
...
CR2: 000000000000000e CR3: 000000004b1bc003 CR4: 0000000000060ef0
Call Trace:
kcm_create+0x600/0xbf0 [kcm]
__sock_create+0x324/0x750 net/socket.c:1272
...
This is due to race between sock_create and unfinished
register_pernet_device. kcm_create tries to do "net_generic(net,
kcm_net_id)". but kcm_net_id is not initialized yet.
So switch the order of the two to close the race.
This can be reproduced with mutiple processes doing socket(PF_KCM, ...)
and one process doing module removal.
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
There has check NULL on kmem_cache_create on failure in kcm_init,
no need use SLAB_PANIC to panic the system.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Several files have extra line at end of file.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.
Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead. That gets rid of one of the new indirections.
But that doesn't fix the new complexity that is completely unwarranted
for the regular case. The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.
[ This revert is a revert of about 30 different commits, not reverted
individually because that would just be unnecessarily messy - Linus ]
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull aio updates from Al Viro:
"Majority of AIO stuff this cycle. aio-fsync and aio-poll, mostly.
The only thing I'm holding back for a day or so is Adam's aio ioprio -
his last-minute fixup is trivial (missing stub in !CONFIG_BLOCK case),
but let it sit in -next for decency sake..."
* 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
aio: sanitize the limit checking in io_submit(2)
aio: fold do_io_submit() into callers
aio: shift copyin of iocb into io_submit_one()
aio_read_events_ring(): make a bit more readable
aio: all callers of aio_{read,write,fsync,poll} treat 0 and -EIOCBQUEUED the same way
aio: take list removal to (some) callers of aio_complete()
aio: add missing break for the IOCB_CMD_FDSYNC case
random: convert to ->poll_mask
timerfd: convert to ->poll_mask
eventfd: switch to ->poll_mask
pipe: convert to ->poll_mask
crypto: af_alg: convert to ->poll_mask
net/rxrpc: convert to ->poll_mask
net/iucv: convert to ->poll_mask
net/phonet: convert to ->poll_mask
net/nfc: convert to ->poll_mask
net/caif: convert to ->poll_mask
net/bluetooth: convert to ->poll_mask
net/sctp: convert to ->poll_mask
net/tipc: convert to ->poll_mask
...
(resend for properly queueing in patchwork)
kcm_clone() creates kernel socket, which does not take net counter.
Thus, the net may die before the socket is completely destructed,
i.e. kcm_exit_net() is executed before kcm_done().
Reported-by: syzbot+5f1a04e374a635efc426@syzkaller.appspotmail.com
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fun set of conflict resolutions here...
For the mac80211 stuff, these were fortunately just parallel
adds. Trivially resolved.
In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.
In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.
The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.
The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:
====================
Due to bug fixes found by the syzkaller bot and taken into the for-rc
branch after development for the 4.17 merge window had already started
being taken into the for-next branch, there were fairly non-trivial
merge issues that would need to be resolved between the for-rc branch
and the for-next branch. This merge resolves those conflicts and
provides a unified base upon which ongoing development for 4.17 can
be based.
Conflicts:
drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f95
(IB/mlx5: Fix cleanup order on unload) added to for-rc and
commit b5ca15ad7e (IB/mlx5: Add proper representors support)
add as part of the devel cycle both needed to modify the
init/de-init functions used by mlx5. To support the new
representors, the new functions added by the cleanup patch
needed to be made non-static, and the init/de-init list
added by the representors patch needed to be modified to
match the init/de-init list changes made by the cleanup
patch.
Updates:
drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
prototypes added by representors patch to reflect new function
names as changed by cleanup patch
drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
stage list to match new order from cleanup patch
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Need to lock lower socket in order to provide mutual exclusion
with kcm_unattach.
v2: Add Reported-by for syzbot
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Reported-by: syzbot+ea75c0ffcd353d32515f064aaebefc5279e6161e@syzkaller.appspotmail.com
Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
These pernet_operations make pretty simple actions
like variable initialization on init, debug checks
on exit, and so on, and they obviously are able
to be executed in parallel with any others:
vrf_net_ops
lockd_net_ops
grace_net_ops
xfrm6_tunnel_net_ops
kcm_net_ops
tcf_net_ops
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In kcm_attach strp_done is called when sk_user_data is already
set to fail the attach. strp_done needs the strp to be stopped and
warns if it isn't. Call strp_stop in this case to eliminate the
warning message.
Reported-by: syzbot+88dfb55e4c8b770d86e3@syzkaller.appspotmail.com
Fixes: e557124023 ("kcm: Check if sk_user_data already set in kcm_attach"
Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:
for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
done
with de-mangling cleanups yet to come.
NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do. But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.
The next patch from Al will sort out the final differences, and we
should be all done.
Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is needed to prevent sk_user_data being overwritten.
The check is done under the callback lock. This should prevent
a socket from being attached twice to a KCM mux. It also prevents
a socket from being attached for other use cases of sk_user_data
as long as the other cases set sk_user_data under the lock.
Followup work is needed to unify all the use cases of sk_user_data
to use the same locking.
Reported-by: syzbot+114b15f2be420a8886c3@syzkaller.appspotmail.com
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Signed-off-by: Tom Herbert <tom@quantonium.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCP sockets for IPv4 and IPv6 that are not listeners or in closed
stated are allowed to be attached to a KCM mux.
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Reported-by: syzbot+8865eaff7f9acd593945@syzkaller.appspotmail.com
Signed-off-by: Tom Herbert <tom@quantonium.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This changes calling conventions (and simplifies the hell out
the callers). New rules: once struct socket had been passed
to sock_alloc_file(), it's been consumed either by struct file
or by sock_release() done by sock_alloc_file(). Either way
the caller should not do sock_release() after that point.
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
1) it's fput() or sock_release(), not both
2) don't do fd_install() until the last failure exit.
3) not a bug per se, but... don't attach socket to struct file
until it's set up.
Take reserving descriptor into the caller, move fd_install() to the
caller, sanitize failure exits and calling conventions.
Cc: stable@vger.kernel.org # v4.6+
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
IS_ERR() already implies unlikely(), so it can be omitted.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
syzkaller had no problem to trigger a deadlock, attaching a KCM socket
to another one (or itself). (original syzkaller report was a very
confusing lockdep splat during a sendmsg())
It seems KCM claims to only support TCP, but no enforcement is done,
so we might need to add additional checks.
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Generalize strparser from more than just being used in conjunction
with read_sock. strparser will also be used in the send path with
zero proxy. The primary change is to create strp_process function
that performs the critical processing on skbs. The documentation
is also updated to reflect the new uses.
Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
struct kcm_clone only contains fd, and kcm_clone() only
writes this struct, so there is no need to copy it from user.
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no reason to continue after a copy_from_user()
failure.
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix up affected files that include this signal functionality via sched.h.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In commit 98e3862ca2 ("kcm: fix 0-length case for kcm_sendmsg()")
I tried to avoid skb allocation for 0-length case, but missed
a check for NULL pointer in the non EOR case.
Fixes: 98e3862ca2 ("kcm: fix 0-length case for kcm_sendmsg()")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Dmitry reported a kernel warning:
WARNING: CPU: 3 PID: 2936 at net/kcm/kcmsock.c:627
kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627
CPU: 3 PID: 2936 Comm: a.out Not tainted 4.10.0-rc6+ #209
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:15 [inline]
dump_stack+0x2ee/0x3ef lib/dump_stack.c:51
panic+0x1fb/0x412 kernel/panic.c:179
__warn+0x1c4/0x1e0 kernel/panic.c:539
warn_slowpath_null+0x2c/0x40 kernel/panic.c:582
kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627
kcm_sendmsg+0x163a/0x2200 net/kcm/kcmsock.c:1029
sock_sendmsg_nosec net/socket.c:635 [inline]
sock_sendmsg+0xca/0x110 net/socket.c:645
sock_write_iter+0x326/0x600 net/socket.c:848
new_sync_write fs/read_write.c:499 [inline]
__vfs_write+0x483/0x740 fs/read_write.c:512
vfs_write+0x187/0x530 fs/read_write.c:560
SYSC_write fs/read_write.c:607 [inline]
SyS_write+0xfb/0x230 fs/read_write.c:599
entry_SYSCALL_64_fastpath+0x1f/0xc2
when calling syscall(__NR_write, sock2, 0x208aaf27ul, 0x0ul) on a KCM
seqpacket socket. It appears that kcm_sendmsg() does not handle len==0
case correctly, which causes an empty skb is allocated and queued.
Fix this by skipping the skb allocation for len==0 case.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull VFS splice updates from Al Viro:
"There's a bunch of branches this cycle, both mine and from other folks
and I'd rather send pull requests separately.
This one is the conversion of ->splice_read() to ITER_PIPE iov_iter
(and introduction of such). Gets rid of a lot of code in fs/splice.c
and elsewhere; there will be followups, but these are for the next
cycle... Some pipe/splice-related cleanups from Miklos in the same
branch as well"
* 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
pipe: fix comment in pipe_buf_operations
pipe: add pipe_buf_steal() helper
pipe: add pipe_buf_confirm() helper
pipe: add pipe_buf_release() helper
pipe: add pipe_buf_get() helper
relay: simplify relay_file_read()
switch default_file_splice_read() to use of pipe-backed iov_iter
switch generic_file_splice_read() to use of ->read_iter()
new iov_iter flavour: pipe-backed
fuse_dev_splice_read(): switch to add_to_pipe()
skb_splice_bits(): get rid of callback
new helper: add_to_pipe()
splice: lift pipe_lock out of splice_to_pipe()
splice: switch get_iovec_page_array() to iov_iter
splice_to_pipe(): don't open-code wakeup_pipe_readers()
consistent treatment of EFAULT on O_DIRECT read/write
since pipe_lock is the outermost now, we don't need to drop/regain
socket locks around the call of splice_to_pipe() from skb_splice_bits(),
which kills the need to have a socket-specific callback; we can just
call splice_to_pipe() and be done with that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
