linux.git/fs/lockd/svclock.c, branch v3.11

Merge branch 'for-3.11' of git://linux-nfs.org/~bfields/linux

2013-07-17T20:43:55+00:00

Pull nfsd bugfixes from Bruce Fields:
 "Just three minor bugfixes"

* 'for-3.11' of git://linux-nfs.org/~bfields/linux:
  svcrdma: underflow issue in decode_write_list()
  nfsd4: fix minorversion support interface
  lockd: protect nlm_blocked access in nlmsvc_retry_blocked

lockd: protect nlm_blocked access in nlmsvc_retry_blocked

2013-07-11T21:24:07+00:00

In nlmsvc_retry_blocked, the check that the list is non-empty and acquiring
the pointer of the first entry is unprotected by any lock.  This allows a rare
race condition when there is only one entry on the list.  A function such as
nlmsvc_grant_callback() can be called, which will temporarily remove the entry
from the list.  Between the list_empty() and list_entry(),the list may become
empty, causing an invalid pointer to be used as an nlm_block, leading to a
possible crash.

This patch adds the nlm_block_lock around these calls to prevent concurrent
use of the nlm_blocked list.

This was a regression introduced by
f904be9cc77f361d37d71468b13ff3d1a1823dea  "lockd: Mostly remove BKL from
the server".

Cc: Bryan Schumaker 
Cc: stable@vger.kernel.org
Signed-off-by: David Jeffery 
Signed-off-by: J. Bruce Fields

locks: add a new "lm_owner_key" lock operation

2013-06-29T08:57:45+00:00

Currently, the hashing that the locking code uses to add these values
to the blocked_hash is simply calculated using fl_owner field. That's
valid in most cases except for server-side lockd, which validates the
owner of a lock based on fl_owner and fl_pid.

In the case where you have a small number of NFS clients doing a lot
of locking between different processes, you could end up with all
the blocked requests sitting in a very small number of hash buckets.

Add a new lm_owner_key operation to the lock_manager_operations that
will generate an unsigned long to use as the key in the hashtable.
That function is only implemented for server-side lockd, and simply
XORs the fl_owner and fl_pid.

Signed-off-by: Jeff Layton 
Acked-by: J. Bruce Fields 
Signed-off-by: Al Viro

locks: drop the unused filp argument to posix_unblock_lock

2013-06-29T08:57:37+00:00

Signed-off-by: Jeff Layton 
Signed-off-by: Al Viro

new helper: file_inode(file)

2013-02-23T04:31:31+00:00

Signed-off-by: Al Viro

close the race in nlmsvc_free_block()

2012-09-23T00:48:20+00:00

we need to grab mutex before the reference counter reaches 0

Signed-off-by: Al Viro

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2012-08-01T17:26:23+00:00

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
  ...

lockd: shift grabbing a reference to nlm_host into nlm_alloc_call()

2012-07-29T19:09:57+00:00

It's used both for client and server hosts; we can't do nlmclnt_release_host()
on failure exits, since the host might need nlmsvc_release_host(), with BUG_ON()
for calling the wrong one.  Makes life simpler for callers, actually...

Signed-off-by: Al Viro

LockD: pass actual network namespace to grace period management functions

2012-07-27T20:49:22+00:00

Passed network namespace replaced hard-coded init_net

Signed-off-by: Stanislav Kinsbursky 
Signed-off-by: J. Bruce Fields

SUNRPC/LOCKD: Fix build warnings when CONFIG_SUNRPC_DEBUG is undefined

2012-03-21T13:31:44+00:00

Stephen Rothwell reports:
net/sunrpc/rpcb_clnt.c: In function 'rpcb_enc_mapping':
net/sunrpc/rpcb_clnt.c:820:19: warning: unused variable 'task' [-Wunused-variable]
net/sunrpc/rpcb_clnt.c: In function 'rpcb_dec_getport':
net/sunrpc/rpcb_clnt.c:837:19: warning: unused variable 'task' [-Wunused-variable]
net/sunrpc/rpcb_clnt.c: In function 'rpcb_dec_set':
net/sunrpc/rpcb_clnt.c:860:19: warning: unused variable 'task' [-Wunused-variable]
net/sunrpc/rpcb_clnt.c: In function 'rpcb_enc_getaddr':
net/sunrpc/rpcb_clnt.c:892:19: warning: unused variable 'task' [-Wunused-variable]
net/sunrpc/rpcb_clnt.c: In function 'rpcb_dec_getaddr':
net/sunrpc/rpcb_clnt.c:914:19: warning: unused variable 'task' [-Wunused-variable]
fs/lockd/svclock.c:49:20: warning: 'nlmdbg_cookie2a' declared 'static' but never defined [-Wunused-function]

Reported-by: Stephen Rothwell 
Signed-off-by: Trond Myklebust