Commit Graph

691 Commits

Author SHA1 Message Date
David Howells
9efcc4a129 afs: Fix unpinned address list during probing
When it's probing all of a fileserver's interfaces to find which one is
best to use, afs_do_probe_fileserver() takes a lock on the server record
and notes the pointer to the address list.

It doesn't, however, pin the address list, so as soon as it drops the
lock, there's nothing to stop the address list from being freed under
us.

Fix this by taking a ref on the address list inside the locked section
and dropping it at the end of the function.

Fixes: 3bf0fb6f33 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-26 16:04:29 -07:00
Linus Torvalds
1b649e0bca Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Fix deadlock in bpf_send_signal() from Yonghong Song.

 2) Fix off by one in kTLS offload of mlx5, from Tariq Toukan.

 3) Add missing locking in iwlwifi mvm code, from Avraham Stern.

 4) Fix MSG_WAITALL handling in rxrpc, from David Howells.

 5) Need to hold RTNL mutex in tcindex_partial_destroy_work(), from Cong
    Wang.

 6) Fix producer race condition in AF_PACKET, from Willem de Bruijn.

 7) cls_route removes the wrong filter during change operations, from
    Cong Wang.

 8) Reject unrecognized request flags in ethtool netlink code, from
    Michal Kubecek.

 9) Need to keep MAC in reset until PHY is up in bcmgenet driver, from
    Doug Berger.

10) Don't leak ct zone template in act_ct during replace, from Paul
    Blakey.

11) Fix flushing of offloaded netfilter flowtable flows, also from Paul
    Blakey.

12) Fix throughput drop during tx backpressure in cxgb4, from Rahul
    Lakkireddy.

13) Don't let a non-NULL skb->dev leave the TCP stack, from Eric
    Dumazet.

14) TCP_QUEUE_SEQ socket option has to update tp->copied_seq as well,
    also from Eric Dumazet.

15) Restrict macsec to ethernet devices, from Willem de Bruijn.

16) Fix reference leak in some ethtool *_SET handlers, from Michal
    Kubecek.

17) Fix accidental disabling of MSI for some r8169 chips, from Heiner
    Kallweit.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (138 commits)
  net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build
  net: ena: Add PCI shutdown handler to allow safe kexec
  selftests/net/forwarding: define libs as TEST_PROGS_EXTENDED
  selftests/net: add missing tests to Makefile
  r8169: re-enable MSI on RTL8168c
  net: phy: mdio-bcm-unimac: Fix clock handling
  cxgb4/ptp: pass the sign of offset delta in FW CMD
  net: dsa: tag_8021q: replace dsa_8021q_remove_header with __skb_vlan_pop
  net: cbs: Fix software cbs to consider packet sending time
  net/mlx5e: Do not recover from a non-fatal syndrome
  net/mlx5e: Fix ICOSQ recovery flow with Striding RQ
  net/mlx5e: Fix missing reset of SW metadata in Striding RQ reset
  net/mlx5e: Enhance ICOSQ WQE info fields
  net/mlx5_core: Set IB capability mask1 to fix ib_srpt connection failure
  selftests: netfilter: add nfqueue test case
  netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress
  netfilter: nft_fwd_netdev: validate family and chain type
  netfilter: nft_set_rbtree: Detect partial overlaps on insertion
  netfilter: nft_set_rbtree: Introduce and use nft_rbtree_interval_start()
  netfilter: nft_set_pipapo: Separate partial and complete overlap cases on insertion
  ...
2020-03-25 13:58:05 -07:00
David Howells
7d7587db0d afs: Fix client call Rx-phase signal handling
Fix the handling of signals in client rxrpc calls made by the afs
filesystem.  Ignore signals completely, leaving call abandonment or
connection loss to be detected by timeouts inside AF_RXRPC.

Allowing a filesystem call to be interrupted after the entire request has
been transmitted and an abort sent means that the server may or may not
have done the action - and we don't know.  It may even be worse than that
for older servers.

Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-13 23:04:35 +00:00
David Howells
dde9f09558 afs: Fix handling of an abort from a service handler
When an AFS service handler function aborts a call, AF_RXRPC marks the call
as complete - which means that it's not going to get any more packets from
the receiver.  This is a problem because reception of the final ACK is what
triggers afs_deliver_to_call() to drop the final ref on the afs_call
object.

Instead, aborted AFS service calls may then just sit around waiting for
ever or until they're displaced by a new call on the same connection
channel or a connection-level abort.

Fix this by calling afs_set_call_complete() to finalise the afs_call struct
representing the call.

However, we then need to drop the ref that stops the call from being
deallocated.  We can do this in afs_set_call_complete(), as the work queue
is holding a separate ref of its own, but then we shouldn't do it in
afs_process_async_call() and afs_delete_async_call().

call->drop_ref is set to indicate that a ref needs dropping for a call and
this is dealt with when we transition a call to AFS_CALL_COMPLETE.

But then we also need to get rid of the ref that pins an asynchronous
client call.  We can do this by the same mechanism, setting call->drop_ref
for an async client call too.

We can also get rid of call->incoming since nothing ever sets it and only
one thing ever checks it (futilely).


A trace of the rxrpc_call and afs_call struct ref counting looks like:

          <idle>-0     [001] ..s5   164.764892: rxrpc_call: c=00000002 SEE u=3 sp=rxrpc_new_incoming_call+0x473/0xb34 a=00000000442095b5
          <idle>-0     [001] .Ns5   164.766001: rxrpc_call: c=00000002 QUE u=4 sp=rxrpc_propose_ACK+0xbe/0x551 a=00000000442095b5
          <idle>-0     [001] .Ns4   164.766005: rxrpc_call: c=00000002 PUT u=3 sp=rxrpc_new_incoming_call+0xa3f/0xb34 a=00000000442095b5
          <idle>-0     [001] .Ns7   164.766433: afs_call: c=00000002 WAKE  u=2 o=11 sp=rxrpc_notify_socket+0x196/0x33c
     kworker/1:2-1810  [001] ...1   164.768409: rxrpc_call: c=00000002 SEE u=3 sp=rxrpc_process_call+0x25/0x7ae a=00000000442095b5
     kworker/1:2-1810  [001] ...1   164.769439: rxrpc_tx_packet: c=00000002 e9f1a7a8:95786a88:00000008:09c5 00000001 00000000 02 22 ACK CallAck
     kworker/1:2-1810  [001] ...1   164.769459: rxrpc_call: c=00000002 PUT u=2 sp=rxrpc_process_call+0x74f/0x7ae a=00000000442095b5
     kworker/1:2-1810  [001] ...1   164.770794: afs_call: c=00000002 QUEUE u=3 o=12 sp=afs_deliver_to_call+0x449/0x72c
     kworker/1:2-1810  [001] ...1   164.770829: afs_call: c=00000002 PUT   u=2 o=12 sp=afs_process_async_call+0xdb/0x11e
     kworker/1:2-1810  [001] ...2   164.771084: rxrpc_abort: c=00000002 95786a88:00000008 s=0 a=1 e=1 K-1
     kworker/1:2-1810  [001] ...1   164.771461: rxrpc_tx_packet: c=00000002 e9f1a7a8:95786a88:00000008:09c5 00000002 00000000 04 00 ABORT CallAbort
     kworker/1:2-1810  [001] ...1   164.771466: afs_call: c=00000002 PUT   u=1 o=12 sp=SRXAFSCB_ProbeUuid+0xc1/0x106

The abort generated in SRXAFSCB_ProbeUuid(), labelled "K-1", indicates that
the local filesystem/cache manager didn't recognise the UUID as its own.

Fixes: 2067b2b3f4 ("afs: Fix the CB.ProbeUuid service handler to reply correctly")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-13 23:04:35 +00:00
David Howells
4636cf184d afs: Fix some tracing details
Fix a couple of tracelines to indicate the usage count after the atomic op,
not the usage count before it to be consistent with other afs and rxrpc
trace lines.

Change the wording of the afs_call_trace_work trace ID label from "WORK" to
"QUEUE" to reflect the fact that it's queueing work, not doing work.

Fixes: 341f741f04 ("afs: Refcount the afs_call struct")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-13 23:04:34 +00:00
David Howells
e138aa7d32 rxrpc: Fix call interruptibility handling
Fix the interruptibility of kernel-initiated client calls so that they're
either only interruptible when they're waiting for a call slot to come
available or they're not interruptible at all.  Either way, they're not
interruptible during transmission.

This should help prevent StoreData calls from being interrupted when
writeback is in progress.  It doesn't, however, handle interruption during
the receive phase.

Userspace-initiated calls are still interruptable.  After the signal has
been handled, sendmsg() will return the amount of data copied out of the
buffer and userspace can perform another sendmsg() call to continue
transmission.

Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-13 23:04:30 +00:00
Jann Horn
ddd2b85ff7 afs: Use kfree_rcu() instead of casting kfree() to rcu_callback_t
afs_put_addrlist() casts kfree() to rcu_callback_t. Apart from being wrong
in theory, this might also blow up when people start enforcing function
types via compiler instrumentation, and it means the rcu_head has to be
first in struct afs_addr_list.

Use kfree_rcu() instead, it's simpler and more correct.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-13 10:47:33 -07:00
Linus Torvalds
c9d35ee049 Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs file system parameter updates from Al Viro:
 "Saner fs_parser.c guts and data structures. The system-wide registry
  of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
  the horror switch() in fs_parse() that would have to grow another case
  every time something got added to that system-wide registry.

  New syntax types can be added by filesystems easily now, and their
  namespace is that of functions - not of system-wide enum members. IOW,
  they can be shared or kept private and if some turn out to be widely
  useful, we can make them common library helpers, etc., without having
  to do anything whatsoever to fs_parse() itself.

  And we already get that kind of requests - the thing that finally
  pushed me into doing that was "oh, and let's add one for timeouts -
  things like 15s or 2h". If some filesystem really wants that, let them
  do it. Without somebody having to play gatekeeper for the variants
  blessed by direct support in fs_parse(), TYVM.

  Quite a bit of boilerplate is gone. And IMO the data structures make a
  lot more sense now. -200LoC, while we are at it"

* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
  tmpfs: switch to use of invalfc()
  cgroup1: switch to use of errorfc() et.al.
  procfs: switch to use of invalfc()
  hugetlbfs: switch to use of invalfc()
  cramfs: switch to use of errofc() et.al.
  gfs2: switch to use of errorfc() et.al.
  fuse: switch to use errorfc() et.al.
  ceph: use errorfc() and friends instead of spelling the prefix out
  prefix-handling analogues of errorf() and friends
  turn fs_param_is_... into functions
  fs_parse: handle optional arguments sanely
  fs_parse: fold fs_parameter_desc/fs_parameter_spec
  fs_parser: remove fs_parameter_description name field
  add prefix to fs_context->log
  ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
  new primitive: __fs_parse()
  switch rbd and libceph to p_log-based primitives
  struct p_log, variants of warnf() et.al. taking that one instead
  teach logfc() to handle prefices, give it saner calling conventions
  get rid of cg_invalf()
  ...
2020-02-08 13:26:41 -08:00
Al Viro
d7167b1499 fs_parse: fold fs_parameter_desc/fs_parameter_spec
The former contains nothing but a pointer to an array of the latter...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:37 -05:00
Eric Sandeen
96cafb9ccb fs_parser: remove fs_parameter_description name field
Unused now.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:36 -05:00
Al Viro
5eede62529 fold struct fs_parameter_enum into struct constant_table
no real difference now

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 00:12:50 -05:00
Al Viro
2710c957a8 fs_parse: get rid of ->enums
Don't do a single array; attach them to fsparam_enum() entry
instead.  And don't bother trying to embed the names into those -
it actually loses memory, with no real speedup worth mentioning.

Simplifies validation as well.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 00:12:50 -05:00
David Howells
a45ea48e2b afs: Fix characters allowed into cell names
The afs filesystem needs to prohibit certain characters from cell names,
such as '/', as these are used to form filenames in procfs, leading to
the following warning being generated:

	WARNING: CPU: 0 PID: 3489 at fs/proc/generic.c:178

Fix afs_alloc_cell() to disallow nonprintable characters, '/', '@' and
names that begin with a dot.

Remove the check for "@cell" as that is then redundant.

This can be tested by running:

	echo add foo/.bar 1.2.3.4 >/proc/fs/afs/cells

Note that we will also need to deal with:

 - Names ending in ".invalid" shouldn't be passed to the DNS.

 - Names that contain non-valid domainname chars shouldn't be passed to
   the DNS.

 - DNS replies that say "your-dns-needs-immediate-attention.<gTLD>" and
   replies containing A records that say 127.0.53.53 should be
   considered invalid.
   [https://www.icann.org/en/system/files/files/name-collision-mitigation-01aug14-en.pdf]

but these need to be dealt with by the kafs-client DNS program rather
than the kernel.

Reported-by: syzbot+b904ba7c947a37b4b291@syzkaller.appspotmail.com
Cc: stable@kernel.org
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-26 08:54:04 -08:00
Linus Torvalds
e033e7d4a8 Merge branch 'dhowells' (patches from DavidH)
Merge misc fixes from David Howells.

Two afs fixes and a key refcounting fix.

* dhowells:
  afs: Fix afs_lookup() to not clobber the version on a new dentry
  afs: Fix use-after-loss-of-ref
  keys: Fix request_key() cache
2020-01-14 09:56:31 -08:00
David Howells
f52b83b0b1 afs: Fix afs_lookup() to not clobber the version on a new dentry
Fix afs_lookup() to not clobber the version set on a new dentry by
afs_do_lookup() - especially as it's using the wrong version of the
version (we need to use the one given to us by whatever op the dir
contents correspond to rather than what's in the afs_vnode).

Fixes: 9dd0b82ef5 ("afs: Fix missing dentry data version updating")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-14 09:40:06 -08:00
David Howells
40a708bd62 afs: Fix use-after-loss-of-ref
afs_lookup() has a tracepoint to indicate the outcome of
d_splice_alias(), passing it the inode to retrieve the fid from.
However, the function gave up its ref on that inode when it called
d_splice_alias(), which may have failed and dropped the inode.

Fix this by caching the fid.

Fixes: 80548b0399 ("afs: Add more tracepoints")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-14 09:40:06 -08:00
David Howells
50559800b7 afs: Show volume name in /proc/net/afs/<cell>/volumes
Show the name of each volume in /proc/net/afs/<cell>/volumes to make it
easier to work out the name corresponding to a volume ID.  This makes it
easier to work out which mounts in /proc/mounts correspond to which volume
ID.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
2019-12-11 17:48:20 +00:00
David Howells
106bc79843 afs: Fix missing cell comparison in afs_test_super()
Fix missing cell comparison in afs_test_super().  Without this, any pair
volumes that have the same volume ID will share a superblock, no matter the
cell, unless they're in different network namespaces.

Normally, most users will only deal with a single cell and so they won't
see this.  Even if they do look into a second cell, they won't see a
problem unless they happen to hit a volume with the same ID as one they've
already got mounted.

Before the patch:

    # ls /afs/grand.central.org/archive
    linuxdev/  mailman/  moin/  mysql/  pipermail/  stage/  twiki/
    # ls /afs/kth.se/
    linuxdev/  mailman/  moin/  mysql/  pipermail/  stage/  twiki/
    # cat /proc/mounts | grep afs
    none /afs afs rw,relatime,dyn,autocell 0 0
    #grand.central.org:root.cell /afs/grand.central.org afs ro,relatime 0 0
    #grand.central.org:root.archive /afs/grand.central.org/archive afs ro,relatime 0 0
    #grand.central.org:root.archive /afs/kth.se afs ro,relatime 0 0

After the patch:

    # ls /afs/grand.central.org/archive
    linuxdev/  mailman/  moin/  mysql/  pipermail/  stage/  twiki/
    # ls /afs/kth.se/
    admin/        common/  install/  OldFiles/  service/  system/
    bakrestores/  home/    misc/     pkg/       src/      wsadmin/
    # cat /proc/mounts | grep afs
    none /afs afs rw,relatime,dyn,autocell 0 0
    #grand.central.org:root.cell /afs/grand.central.org afs ro,relatime 0 0
    #grand.central.org:root.archive /afs/grand.central.org/archive afs ro,relatime 0 0
    #kth.se:root.cell /afs/kth.se afs ro,relatime 0 0

Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Carsten Jacobi <jacobi@de.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
cc: Todd DeSantis <atd@us.ibm.com>
2019-12-11 17:47:51 +00:00
David Howells
1da4bd9f9d afs: Fix creation calls in the dynamic root to fail with EOPNOTSUPP
Fix the lookup method on the dynamic root directory such that creation
calls, such as mkdir, open(O_CREAT), symlink, etc. fail with EOPNOTSUPP
rather than failing with some odd error (such as EEXIST).

lookup() itself tries to create automount directories when it is invoked.
These are cached locally in RAM and not committed to storage.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
2019-12-11 17:47:51 +00:00
David Howells
158d583353 afs: Fix mountpoint parsing
Each AFS mountpoint has strings that define the target to be mounted.  This
is required to end in a dot that is supposed to be stripped off.  The
string can include suffixes of ".readonly" or ".backup" - which are
supposed to come before the terminal dot.  To add to the confusion, the "fs
lsmount" afs utility does not show the terminal dot when displaying the
string.

The kernel mount source string parser, however, assumes that the terminal
dot marks the suffix and that the suffix is always "" and is thus ignored.
In most cases, there is no suffix and this is not a problem - but if there
is a suffix, it is lost and this affects the ability to mount the correct
volume.

The command line mount command, on the other hand, is expected not to
include a terminal dot - so the problem doesn't arise there.

Fix this by making sure that the dot exists and then stripping it when
passing the string to the mount configuration.

Fixes: bec5eb6141 ("AFS: Implement an autocell mount capability [ver #2]")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
2019-12-11 16:56:54 +00:00
David Howells
bcbccaf2ed afs: Fix SELinux setting security label on /afs
Make the AFS dynamic root superblock R/W so that SELinux can set the
security label on it.  Without this, upgrades to, say, the Fedora
filesystem-afs RPM fail if afs is mounted on it because the SELinux label
can't be (re-)applied.

It might be better to make it possible to bypass the R/O check for LSM
label application through setxattr.

Fixes: 4d673da145 ("afs: Support the AFS dynamic root")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: selinux@vger.kernel.org
cc: linux-security-module@vger.kernel.org
2019-12-09 16:37:36 +00:00
Marc Dionne
9bd0160d12 afs: Fix afs_find_server lookups for ipv4 peers
afs_find_server tries to find a server that has an address that
matches the transport address of an rxrpc peer.  The code assumes
that the transport address is always ipv6, with ipv4 represented
as ipv4 mapped addresses, but that's not the case.  If the transport
family is AF_INET, srx->transport.sin6.sin6_addr.s6_addr32[] will
be beyond the actual ipv4 address and will always be 0, and all
ipv4 addresses will be seen as matching.

As a result, the first ipv4 address seen on any server will be
considered a match, and the server returned may be the wrong one.

One of the consequences is that callbacks received over ipv4 will
only be correctly applied for the server that happens to have the
first ipv4 address on the fs_addresses4 list.  Callbacks over ipv4
from all other servers are dropped, causing the client to serve stale
data.

This is fixed by looking at the transport family, and comparing ipv4
addresses based on a sockaddr_in structure rather than a sockaddr_in6.

Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-12-09 15:04:43 +00:00
Linus Torvalds
4a55d362ff AFS development
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Merge tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS updates from David Howells:
 "Minor cleanups and fix:

   - Minor fix to make some debugging statements display information
     from the correct iov_iter.

   - Rename some members and variables to make things more obvious or
     consistent.

   - Provide a helper to wrap increments of the usage count on the
     afs_read struct.

   - Use scnprintf() to print into a stack buffer rather than sprintf().

   - Remove some set but unused variables"

* tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Remove set but not used variable 'ret'
  afs: Remove set but not used variables 'before', 'after'
  afs: xattr: use scnprintf
  afs: Introduce an afs_get_read() refcount helper
  afs: Rename desc -> req in afs_fetch_data()
  afs: Switch the naming of call->iter and call->_iter
  afs: Use call->_iter not &call->iter in debugging statements
2019-11-30 10:57:22 -08:00
Linus Torvalds
1ae78780ed Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Dynamic tick (nohz) updates, perhaps most notably changes to force
     the tick on when needed due to lengthy in-kernel execution on CPUs
     on which RCU is waiting.

   - Linux-kernel memory consistency model updates.

   - Replace rcu_swap_protected() with rcu_prepace_pointer().

   - Torture-test updates.

   - Documentation updates.

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  security/safesetid: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/sched: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/netfilter: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/core: Replace rcu_swap_protected() with rcu_replace_pointer()
  bpf/cgroup: Replace rcu_swap_protected() with rcu_replace_pointer()
  fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
  drivers/scsi: Replace rcu_swap_protected() with rcu_replace_pointer()
  drm/i915: Replace rcu_swap_protected() with rcu_replace_pointer()
  x86/kvm/pmu: Replace rcu_swap_protected() with rcu_replace_pointer()
  rcu: Upgrade rcu_swap_protected() to rcu_replace_pointer()
  rcu: Suppress levelspread uninitialized messages
  rcu: Fix uninitialized variable in nocb_gp_wait()
  rcu: Update descriptions for rcu_future_grace_period tracepoint
  rcu: Update descriptions for rcu_nocb_wake tracepoint
  rcu: Remove obsolete descriptions for rcu_barrier tracepoint
  rcu: Ensure that ->rcu_urgent_qs is set before resched IPI
  workqueue: Convert for_each_wq to use built-in list check
  rcu: Several rcu_segcblist functions can be static
  rcu: Remove unused function hlist_bl_del_init_rcu()
  Documentation: Rename rcu_node_context_switch() to rcu_note_context_switch()
  ...
2019-11-26 15:42:43 -08:00
Linus Torvalds
436b2a8039 Printk changes for 5.5
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Merge tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk

Pull printk updates from Petr Mladek:

 - Allow to print symbolic error names via new %pe modifier.

 - Use pr_warn() instead of the remaining pr_warning() calls. Fix
   formatting of the related lines.

 - Add VSPRINTF entry to MAINTAINERS.

* tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (32 commits)
  checkpatch: don't warn about new vsprintf pointer extension '%pe'
  MAINTAINERS: Add VSPRINTF
  tools lib api: Renaming pr_warning to pr_warn
  ASoC: samsung: Use pr_warn instead of pr_warning
  lib: cpu_rmap: Use pr_warn instead of pr_warning
  trace: Use pr_warn instead of pr_warning
  dma-debug: Use pr_warn instead of pr_warning
  vgacon: Use pr_warn instead of pr_warning
  fs: afs: Use pr_warn instead of pr_warning
  sh/intc: Use pr_warn instead of pr_warning
  scsi: Use pr_warn instead of pr_warning
  platform/x86: intel_oaktrail: Use pr_warn instead of pr_warning
  platform/x86: asus-laptop: Use pr_warn instead of pr_warning
  platform/x86: eeepc-laptop: Use pr_warn instead of pr_warning
  oprofile: Use pr_warn instead of pr_warning
  of: Use pr_warn instead of pr_warning
  macintosh: Use pr_warn instead of pr_warning
  idsn: Use pr_warn instead of pr_warning
  ide: Use pr_warn instead of pr_warning
  crypto: n2: Use pr_warn instead of pr_warning
  ...
2019-11-25 19:40:40 -08:00
Marc Dionne
b485275f1a afs: Fix large file support
By default s_maxbytes is set to MAX_NON_LFS, which limits the usable
file size to 2GB, enforced by the vfs.

Commit b9b1f8d593 ("AFS: write support fixes") added support for the
64-bit fetch and store server operations, but did not change this value.
As a result, attempts to write past the 2G mark result in EFBIG errors:

 $ dd if=/dev/zero of=foo bs=1M count=1 seek=2048
 dd: error writing 'foo': File too large

Set s_maxbytes to MAX_LFS_FILESIZE.

Fixes: b9b1f8d593 ("AFS: write support fixes")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-22 14:19:26 -08:00
Marc Dionne
cd340703c2 afs: Fix possible assert with callbacks from yfs servers
Servers sending callback breaks to the YFS_CM_SERVICE service may
send up to YFSCBMAX (1024) fids in a single RPC.  Anything over
AFSCBMAX (50) will cause the assert in afs_break_callbacks to trigger.

Remove the assert, as the count has already been checked against
the appropriate max values in afs_deliver_cb_callback and
afs_deliver_yfs_cb_callback.

Fixes: 35dbfba311 ("afs: Implement the YFS cache manager service")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-22 14:19:26 -08:00
zhengbin
4fe171bb81 afs: Remove set but not used variable 'ret'
Fixes gcc '-Wunused-but-set-variable' warning:

fs/afs/server.c: In function afs_install_server:
fs/afs/server.c:157:6: warning: variable ret set but not used [-Wunused-but-set-variable]

It is not used since commit d2ddc776a4 ("afs:
Overhaul volume and server record caching and fileserver rotation")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 20:36:04 +00:00
zhengbin
51590df4f3 afs: Remove set but not used variables 'before', 'after'
Fixes gcc '-Wunused-but-set-variable' warning:

fs/afs/dir_edit.c: In function afs_set_contig_bits:
fs/afs/dir_edit.c:75:20: warning: variable after set but not used [-Wunused-but-set-variable]
fs/afs/dir_edit.c: In function afs_set_contig_bits:
fs/afs/dir_edit.c:75:12: warning: variable before set but not used [-Wunused-but-set-variable]
fs/afs/dir_edit.c: In function afs_clear_contig_bits:
fs/afs/dir_edit.c💯20: warning: variable after set but not used [-Wunused-but-set-variable]
fs/afs/dir_edit.c: In function afs_clear_contig_bits:
fs/afs/dir_edit.c💯12: warning: variable before set but not used [-Wunused-but-set-variable]

They are never used since commit 63a4681ff3.

Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 20:36:00 +00:00
Mark Salyzyn
2e2fae99d1 afs: xattr: use scnprintf
sprintf and snprintf are fragile in future maintenance, switch to
using scnprintf to ensure no accidental Use After Free conditions
are introduced.

Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:17 +00:00
David Howells
d4438a2529 afs: Introduce an afs_get_read() refcount helper
Introduce an afs_get_read() helper to get a reference on an afs_read
object.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:17 +00:00
David Howells
0b9c0174d6 afs: Rename desc -> req in afs_fetch_data()
Rename the desc parameter to req in afs_fetch_data() for consistency with
other functions.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:17 +00:00
David Howells
fc27612249 afs: Switch the naming of call->iter and call->_iter
Change the name of call->iter to call->def_iter to represent the default
iterator.

Change the name of call->_iter to call->iter to represent the iterator
actually being used.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:17 +00:00
David Howells
1b87b025b4 afs: Use call->_iter not &call->iter in debugging statements
Use call->_iter not &call->iter in debugging statements as the latter is a
convenience iter whereas the former represents we're actually doing at the
moment.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:16 +00:00
David Howells
c74386d50f afs: Fix missing timeout reset
In afs_wait_for_call_to_complete(), rather than immediately aborting an
operation if a signal occurs, the code attempts to wait for it to
complete, using a schedule timeout of 2*RTT (or min 2 jiffies) and a
check that we're still receiving relevant packets from the server before
we consider aborting the call.  We may even ping the server to check on
the status of the call.

However, there's a missing timeout reset in the event that we do
actually get a packet to process, such that if we then get a couple of
short stalls, we then time out when progress is actually being made.

Fix this by resetting the timeout any time we get something to process.
If it's the failure of the call then the call state will get changed and
we'll exit the loop shortly thereafter.

A symptom of this is data fetches and stores failing with EINTR when
they really shouldn't.

Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-19 14:36:38 -08:00
David Howells
a28f239e29 afs: Fix race in commit bulk status fetch
When a lookup is done, the afs filesystem will perform a bulk status-fetch
operation on the requested vnode (file) plus the next 49 other vnodes from
the directory list (in AFS, directory contents are downloaded as blobs and
parsed locally).  When the results are received, it will speculatively
populate the inode cache from the extra data.

However, if the lookup races with another lookup on the same directory, but
for a different file - one that's in the 49 extra fetches, then if the bulk
status-fetch operation finishes first, it will try and update the inode
from the other lookup.

If this other inode is still in the throes of being created, however, this
will cause an assertion failure in afs_apply_status():

	BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));

on or about fs/afs/inode.c:175 because it expects data to be there already
that it can compare to.

Fix this by skipping the update if the inode is being created as the
creator will presumably set up the inode with the same information.

Fixes: 39db9815da ("afs: Fix application of the results of a inline bulk status fetch")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-15 10:28:02 -08:00
Paul E. McKenney
62860da708 fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
This commit replaces the use of rcu_swap_protected() with the more
intuitively appealing rcu_replace_pointer() as a step towards removing
rcu_swap_protected().

Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@mail.gmail.com/
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
[ paulmck: From rcu_replace() to rcu_replace_pointer() per Ingo Molnar. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: David Howells <dhowells@redhat.com>
Cc: <linux-afs@lists.infradead.org>
Cc: <linux-kernel@vger.kernel.org>
2019-10-30 08:44:27 -07:00
Kefeng Wang
a4e530ae7e fs: afs: Use pr_warn instead of pr_warning
As said in commit f2c2cbcc35 ("powerpc: Use pr_warn instead of
pr_warning"), removing pr_warning so all logging messages use a
consistent <prefix>_warn style. Let's do it.

Link: http://lkml.kernel.org/r/20191018031850.48498-23-wangkefeng.wang@huawei.com
To: linux-kernel@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-10-18 15:01:55 +02:00
Linus Torvalds
1eb80d6ffb Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 "A couple of misc patches"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  afs dynroot: switch to simple_dir_operations
  fs/handle.c - fix up kerneldoc
2019-09-29 19:42:07 -07:00
Al Viro
473ef57ad8 afs dynroot: switch to simple_dir_operations
no point reinventing it (with wrong ->read(), BTW).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-15 12:19:48 -04:00
David Howells
a0753c2900 afs: Support RCU pathwalk
Make afs_permission() and afs_d_revalidate() do initial checks in RCU-mode
pathwalk to reduce latency in pathwalk elements that get done multiple
times.  We don't need to query the server unless we've received a
notification from it that something has changed or the callback has
expired.

This requires that we can request a key and check permits under RCU
conditions if we need to.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
David Howells
8b6a666a97 afs: Provide an RCU-capable key lookup
Provide an RCU-capable key lookup function.  We don't want to call
afs_request_key() in RCU-mode pathwalk as request_key() might sleep, even if
we don't ask it to construct anything as it might find a key that is currently
undergoing construction.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
David Howells
23a289137a afs: Use afs_extract_discard() rather than iov_iter_discard()
Use afs_extract_discard() rather than iov_iter_discard() as the former is a
wrapper for the latter, providing a place to put tracepoints.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
YueHaibing
52c9c13078 afs: remove unused variable 'afs_zero_fid'
fs/afs/fsclient.c:18:29: warning:
 afs_zero_fid defined but not used [-Wunused-const-variable=]

It is never used since commit 025db80c9e ("afs: Trace
the initiation and completion of client calls")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
YueHaibing
cacf2d7dcf afs: remove unused variable 'afs_voltypes'
fs/afs/volume.c:15:26: warning:
 afs_voltypes defined but not used [-Wunused-const-variable=]

It is not used since commit d2ddc776a4 ("afs: Overhaul
volume and server record caching and fileserver rotation")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
YueHaibing
7533be858f afs: use correct afs_call_type in yfs_fs_store_opaque_acl2
It seems that 'yfs_RXYFSStoreOpaqueACL2' should be use in
yfs_fs_store_opaque_acl2().

Fixes: f5e4546347 ("afs: Implement YFS ACL setting")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-08-22 13:33:27 +01:00
Marc Dionne
c4c613ff08 afs: Fix possible oops in afs_lookup trace event
The afs_lookup trace event can cause the following:

[  216.576777] BUG: kernel NULL pointer dereference, address: 000000000000023b
[  216.576803] #PF: supervisor read access in kernel mode
[  216.576813] #PF: error_code(0x0000) - not-present page
...
[  216.576913] RIP: 0010:trace_event_raw_event_afs_lookup+0x9e/0x1c0 [kafs]

If the inode from afs_do_lookup() is an error other than ENOENT, or if it
is ENOENT and afs_try_auto_mntpt() returns an error, the trace event will
try to dereference the error pointer as a valid pointer.

Use IS_ERR_OR_NULL to only pass a valid pointer for the trace, or NULL.

Ideally the trace would include the error value, but for now just avoid
the oops.

Fixes: 80548b0399 ("afs: Add more tracepoints")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-08-22 13:33:26 +01:00
David Howells
a5fb8e6c02 afs: Fix leak in afs_lookup_cell_rcu()
Fix a leak on the cell refcount in afs_lookup_cell_rcu() due to
non-clearance of the default error in the case a NULL cell name is passed
and the workstation default cell is used.

Also put a bit at the end to make sure we don't leak a cell ref if we're
going to be returning an error.

This leak results in an assertion like the following when the kafs module is
unloaded:

	AFS: Assertion failed
	2 == 1 is false
	0x2 == 0x1 is false
	------------[ cut here ]------------
	kernel BUG at fs/afs/cell.c:770!
	...
	RIP: 0010:afs_manage_cells+0x220/0x42f [kafs]
	...
	 process_one_work+0x4c2/0x82c
	 ? pool_mayday_timeout+0x1e1/0x1e1
	 ? do_raw_spin_lock+0x134/0x175
	 worker_thread+0x336/0x4a6
	 ? rescuer_thread+0x4af/0x4af
	 kthread+0x1de/0x1ee
	 ? kthread_park+0xd4/0xd4
	 ret_from_fork+0x24/0x30

Fixes: 989782dcdc ("afs: Overhaul cell database management")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-08-22 13:33:26 +01:00
David Howells
9dd0b82ef5 afs: Fix missing dentry data version updating
In the in-kernel afs filesystem, the d_fsdata dentry field is used to hold
the data version of the parent directory when it was created or when
d_revalidate() last caused it to be updated.  This is compared to the
->invalid_before field in the directory inode, rather than the actual data
version number, thereby allowing changes due to local edits to be ignored.
Only if the server data version gets bumped unexpectedly (eg. by a
competing client), do we need to revalidate stuff.

However, the d_fsdata field should also be updated if an rpc op is
performed that modifies that particular dentry.  Such ops return the
revised data version of the directory(ies) involved, so we should use that.

This is particularly problematic for rename, since a dentry from one
directory may be moved directly into another directory (ie. mv a/x b/x).
It would then be sporting the wrong data version - and if this is in the
future, for the destination directory, revalidations would be missed,
leading to foreign renames and hard-link deletion being missed.

Fix this by the following means:

 (1) Return the data version number from operations that read the directory
     contents - if they issue the read.  This starts in afs_dir_iterate()
     and is used, ignored or passed back by its callers.

 (2) In afs_lookup*(), set the dentry version to the version returned by
     (1) before d_splice_alias() is called and the dentry published.

 (3) In afs_d_revalidate(), set the dentry version to that returned from
     (1) if an rpc call was issued.  This means that if a parallel
     procedure, such as mkdir(), modifies the directory, we won't
     accidentally use the data version from that.

 (4) In afs_{mkdir,create,link,symlink}(), set the new dentry's version to
     the directory data version before d_instantiate() is called.

 (5) In afs_{rmdir,unlink}, update the target dentry's version to the
     directory data version as soon as we've updated the directory inode.

 (6) In afs_rename(), we need to unhash the old dentry before we start so
     that we don't get afs_d_revalidate() reverting the version change in
     cross-directory renames.

     We then need to set both the old and the new dentry versions the data
     version of the new directory before we call d_move() as d_move() will
     rehash them.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-07-30 14:38:52 +01:00
David Howells
5dc84855b0 afs: Only update d_fsdata if different in afs_d_revalidate()
In the in-kernel afs filesystem, d_fsdata is set with the data version of
the parent directory.  afs_d_revalidate() will update this to the current
directory version, but it shouldn't do this if it the value it read from
d_fsdata is the same as no lock is held and cmpxchg() is not used.

Fix the code to only change the value if it is different from the current
directory version.

Fixes: 260a980317 ("[AFS]: Add "directory write" support.")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-07-30 14:38:51 +01:00