Commit graph

9178 commits

Author SHA1 Message Date
Chuck Lever
367c8c7bd9 lockd: Pass "struct sockaddr *" to new failover-by-IP function
Pass a more generic socket address type to nlmsvc_unlock_all_by_ip() to
allow for future support of IPv6.  Also provide additional sanity
checking in failover_unlock_ip() when constructing the server's IP
address.

As an added bonus, provide clean kerneldoc comments on related NLM
interfaces which were recently added.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-15 16:11:29 -04:00
J. Bruce Fields
560de0e659 lockd: get host reference in nlmsvc_create_block() instead of callers
It may not be obvious (till you look at the definition of
nlm_alloc_call()) that a function like nlmsvc_create_block() should
consume a reference on success or failure, so I find it clearer if it
takes the reference it needs itself.

And both callers already do this immediately before the call anyway.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-15 15:40:25 -04:00
J. Bruce Fields
6d7bbbbacc lockd: minor svclock.c style fixes
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-15 15:28:43 -04:00
Jeff Layton
6cde4de807 lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_lock
nlmsvc_lock calls nlmsvc_lookup_host to find a nlm_host struct. The
callers of this function, however, call nlmsvc_retrieve_args or
nlm4svc_retrieve_args, which also return a nlm_host struct.

Change nlmsvc_lock to take a host arg instead of calling
nlmsvc_lookup_host itself and change the callers to pass a pointer to
the nlm_host they've already found.

Since nlmsvc_testlock() now just uses the caller's reference, we no
longer need to get or release it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-15 14:53:33 -04:00
Jeff Layton
8f920d5e29 lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_testlock
nlmsvc_testlock calls nlmsvc_lookup_host to find a nlm_host struct. The
callers of this functions, however, call nlmsvc_retrieve_args or
nlm4svc_retrieve_args, which also return a nlm_host struct.

Change nlmsvc_testlock to take a host arg instead of calling
nlmsvc_lookup_host itself and change the callers to pass a pointer to
the nlm_host they've already found.

We take a reference to host in the place where nlmsvc_testlock()
previous did a new lookup, so the reference counting is unchanged from
before.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-15 14:26:52 -04:00
Jeff Layton
b0e92aae15 lockd: nlm_release_host() checks for NULL, caller needn't
No need to check for a NULL argument twice.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-15 12:35:20 -04:00
Benny Halevy
e518f0560a nfsd: take file and mnt write in nfs4_upgrade_open
testing with newpynfs revealed this warning:
Jul  3 07:32:50 buml kernel: writeable file with no mnt_want_write()
Jul  3 07:32:50 buml kernel: ------------[ cut here ]------------
Jul  3 07:32:50 buml kernel: WARNING: at /usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/include/linux/fs.h:855 drop_file_write_access+0x6b/0x7e()
Jul  3 07:32:50 buml kernel: Modules linked in: nfsd auth_rpcgss exportfs nfs lockd nfs_acl sunrpc
Jul  3 07:32:50 buml kernel: Call Trace:
Jul  3 07:32:50 buml kernel: 6eaadc88:  [<6002f471>] warn_on_slowpath+0x54/0x8e
Jul  3 07:32:50 buml kernel: 6eaadcc8:  [<601b790d>] printk+0xa0/0x793
Jul  3 07:32:50 buml kernel: 6eaadd38:  [<601b6205>] __mutex_lock_slowpath+0x1db/0x1ea
Jul  3 07:32:50 buml kernel: 6eaadd68:  [<7107d4d5>] nfs4_preprocess_seqid_op+0x2a6/0x31c [nfsd]
Jul  3 07:32:50 buml kernel: 6eaadda8:  [<60078dc9>] drop_file_write_access+0x6b/0x7e
Jul  3 07:32:50 buml kernel: 6eaaddc8:  [<710804e4>] nfsd4_open_downgrade+0x114/0x1de [nfsd]
Jul  3 07:32:50 buml kernel: 6eaade08:  [<71076215>] nfsd4_proc_compound+0x1ba/0x2dc [nfsd]
Jul  3 07:32:50 buml kernel: 6eaade48:  [<71068221>] nfsd_dispatch+0xe5/0x1c2 [nfsd]
Jul  3 07:32:50 buml kernel: 6eaade88:  [<71312f81>] svc_process+0x3fd/0x714 [sunrpc]
Jul  3 07:32:50 buml kernel: 6eaadea8:  [<60039a81>] kernel_sigprocmask+0xf3/0x100
Jul  3 07:32:50 buml kernel: 6eaadee8:  [<7106874b>] nfsd+0x182/0x29b [nfsd]
Jul  3 07:32:50 buml kernel: 6eaadf48:  [<60021cc9>] run_kernel_thread+0x41/0x4a
Jul  3 07:32:50 buml kernel: 6eaadf58:  [<710685c9>] nfsd+0x0/0x29b [nfsd]
Jul  3 07:32:50 buml kernel: 6eaadf98:  [<60021cb0>] run_kernel_thread+0x28/0x4a
Jul  3 07:32:50 buml kernel: 6eaadfc8:  [<60013829>] new_thread_handler+0x72/0x9c
Jul  3 07:32:50 buml kernel:
Jul  3 07:32:50 buml kernel: ---[ end trace 2426dd7cb2fba3bf ]---

Bruce Fields suggested this (Thanks!):
maybe we need to be doing a mnt_want_write on open_upgrade and mnt_put_write on downgrade?

This patch adds a call to mnt_want_write and file_take_write (which is
doing the actual work).

The counter-calls mnt_drop_write a file_release_write are now being properly
called by drop_file_write_access in the exact path printed by the warning
above.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-07 15:23:34 -04:00
J. Bruce Fields
4f83aa302f nfsd: document open share bit tracking
It's not immediately obvious from the code why we're doing this.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Benny Halevy <bhalevy@panasas.com>
2008-07-07 15:04:50 -04:00
Benny Halevy
695e12f8d2 nfsd: tabulate nfs4 xdr encoding functions
In preparation for minorversion 1

All encoders now return an nfserr status (typically their
nfserr argument).  Unsupported ops go through nfsd4_encode_operation
too, so use nfsd4_encode_noop to encode nothing for their reply body.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-04 16:21:30 -04:00
J. Bruce Fields
e86322f611 Merge branch 'for-bfields' of git://linux-nfs.org/~tomtucker/xprt-switch-2.6 into for-2.6.27 2008-07-03 16:24:06 -04:00
Benny Halevy
b001a1b6aa nfsd: dprint operation names
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-02 19:03:19 -04:00
Benny Halevy
f2feb96bc3 nfsd: nfs4 minorversion decoder vectors
Have separate vectors of operation decoders for each minorversion.
Obsolete ops in newer minorversions have default implementation returning
nfserr_opnotsupp.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-02 15:58:21 -04:00
Benny Halevy
3c375c6f3a nfsd: unsupported nfs4 ops should fail with nfserr_opnotsupp
nfserr_opnotsupp should be returned for unsupported nfs4 ops
rather than nfserr_op_illegal.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-02 15:58:21 -04:00
Benny Halevy
347e0ad9c9 nfsd: tabulate nfs4 xdr decoding functions
In preparation for minorversion 1

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-02 15:58:20 -04:00
Benny Halevy
30cff1ffff nfsd: return nfserr_minor_vers_mismatch when compound minorversion != 0
Check minorversion once before decoding any operation and reject with
nfserr_minor_vers_mismatch if != 0 (this still happens in nfsd4_proc_compound).
In this case return a zero length resultdata array as required by RFC3530.

minorversion 1 processing will have its own vector of decoders.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-02 15:58:20 -04:00
Miklos Szeredi
07cad1d2a4 nfsd: clean up mnt_want_write calls
Multiple mnt_want_write() calls in the switch statement looks really
ugly.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-01 15:22:03 -04:00
Jeff Layton
100766f834 nfsd: treat all shutdown signals as equivalent
knfsd currently uses 2 signal masks when processing requests. A "loose"
mask (SHUTDOWN_SIGS) that it uses when receiving network requests, and
then a more "strict" mask (ALLOWED_SIGS, which is just SIGKILL) that it
allows when doing the actual operation on the local storage.

This is apparently unnecessarily complicated. The underlying filesystem
should be able to sanely handle a signal in the middle of an operation.
This patch removes the signal mask handling from knfsd altogether. When
knfsd is started as a kthread, all signals are ignored. It then allows
all of the signals in SHUTDOWN_SIGS. There's no need to set the mask
as well.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-30 15:27:47 -04:00
Neil Brown
496d6c32d4 nfsd: fix spurious EACCESS in reconnect_path()
Thanks to Frank Van Maarseveen for the original problem report: "A
privileged process on an NFS client which drops privileges after using
them to change the current working directory, will experience incorrect
EACCES after an NFS server reboot. This problem can also occur after
memory pressure on the server, particularly when the client side is
quiet for some time."

This occurs because the filehandle points to a directory whose parents
are no longer in the dentry cache, and we're attempting to reconnect the
directory to its parents without adequate permissions to perform lookups
in the parent directories.

We can therefore fix the problem by acquiring the necessary capabilities
before attempting the reconnection.  We do this only in the
no_subtree_check case, since the documented behavior of the
subtree_check export option requires the server to check that the user
has lookup permissions on all parents.

The subtree_check case still has a problem, since reconnect_path()
unnecessarily requires both read and lookup permissions on all parent
directories.  However, a fix in that case would be more delicate, and
use of subtree_check is already discouraged for other reasons.

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Frank van Maarseveen <frankvm@frankvm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-30 15:24:11 -04:00
Linus Torvalds
747606464b Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-udf-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-udf-2.6:
  udf: Fix regression in UDF anchor block detection
2008-06-29 12:19:02 -07:00
Linus Torvalds
4f46accee4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  [patch 2/3] vfs: dcache cleanups
  [patch 1/3] vfs: dcache sparse fixes
  [patch 3/3] vfs: make d_path() consistent across mount operations
  [patch 4/4] flock: remove unused fields from file_lock_operations
  [patch 3/4] vfs: fix ERR_PTR abuse in generic_readlink
  [patch 2/4] fs: make struct file arg to d_path const
  [patch 1/4] vfs: path_{get,put}() cleanups
  [patch for 2.6.26 4/4] vfs: utimensat(): fix write access check for futimens()
  [patch for 2.6.26 3/4] vfs: utimensat(): fix error checking for {UTIME_NOW,UTIME_OMIT} case
  [patch for 2.6.26 1/4] vfs: utimensat(): ignore tv_sec if tv_nsec == UTIME_OMIT or UTIME_NOW
  [patch for 2.6.26 2/4] vfs: utimensat(): be consistent with utime() for immutable and append-only files
  [PATCH] fix cgroup-inflicted breakage in block_dev.c
2008-06-29 12:14:37 -07:00
Benjamin Marzinski
5af4e7a0be [GFS2] fix gfs2 block allocation (cleaned up)
This patch fixes bz 450641.

This patch changes the computation for zero_metapath_length(), which it
renames to metapath_branch_start(). When you are extending the metadata
tree, The indirect blocks that point to the new data block must either
diverge from the existing tree either at the inode, or at the first
indirect block. They can diverge at the first indirect block because the
inode has room for 483 pointers while the indirect blocks have room for
509 pointers, so when the tree is grown, there is some free space in the
first indirect block. What metapath_branch_start() now computes is the
height where the first indirect block for the new data block is located.
It can either be 1 (if the indirect block diverges from the inode) or 2
(if it diverges from the first indirect block).

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2008-06-24 19:02:28 +01:00
Bob Peterson
17c15da00c [GFS2] BUG: unable to handle kernel paging request at ffff81002690e000
This patch fixes bugzilla bug bz448866: gfs2: BUG: unable to
handle kernel paging request at ffff81002690e000.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2008-06-24 14:17:45 +01:00
Jan Kara
19fd426a18 Merge branch 'master' into for_mm 2008-06-24 11:43:00 +02:00
Tomas Janousek
e8183c2452 udf: Fix regression in UDF anchor block detection
In some cases it could happen that some block passed test in
udf_check_anchor_block() even though udf_read_tagged() refused to read it later
(e.g. because checksum was not correct).  This patch makes
udf_check_anchor_block() use udf_read_tagged() so that the checking is
stricter.

This fixes the regression (certain disks unmountable) caused by commit
423cf6dc04.

Signed-off-by: Tomas Janousek <tomi@nomi.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
2008-06-24 11:38:03 +02:00
Trond Myklebust
03fa9e84e5 NFS: nfs_updatepage(): don't mark page as dirty if an error occurred
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-06-23 17:09:07 -04:00
Trond Myklebust
b7e2445737 NFS: Fix filehandle size comparisons in the mount code
Fix a sign issue in xdr_decode_fhstatus3()
Fix incorrect comparison in nfs_validate_mount_data()

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-06-23 17:09:06 -04:00
Trond Myklebust
33852a1f2b NFS: Reduce the NFS mount code stack usage.
This appears to fix the Oops reported in
  http://bugzilla.kernel.org/show_bug.cgi?id=10826

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-06-23 17:09:05 -04:00
Miklos Szeredi
cdd16d0265 [patch 2/3] vfs: dcache cleanups
Comment from Al Viro: add prepend_name() wrapper.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 13:07:00 -04:00
Miklos Szeredi
31f3e0b3a1 [patch 1/3] vfs: dcache sparse fixes
Fix the following sparse warnings:

fs/dcache.c:2183:19: warning: symbol 'filp_cachep' was not declared. Should it be static?
fs/dcache.c:115:3: warning: context imbalance in 'dentry_iput' - unexpected unlock
fs/dcache.c:188:2: warning: context imbalance in 'dput' - different lock contexts for basic block
fs/dcache.c:400:2: warning: context imbalance in 'prune_one_dentry' - different lock contexts for basic block
fs/dcache.c:431:22: warning: context imbalance in 'prune_dcache' - different lock contexts for basic block
fs/dcache.c:563:2: warning: context imbalance in 'shrink_dcache_sb' - different lock contexts for basic block
fs/dcache.c:1385:6: warning: context imbalance in 'd_delete' - wrong count at exit
fs/dcache.c:1636:2: warning: context imbalance in '__d_unalias' - unexpected unlock
fs/dcache.c:1735:2: warning: context imbalance in 'd_materialise_unique' - different lock contexts for basic block

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 13:06:36 -04:00
Andreas Gruenbacher
be285c712b [patch 3/3] vfs: make d_path() consistent across mount operations
The path that __d_path() computes can become slightly inconsistent when it
races with mount operations: it grabs the vfsmount_lock when traversing mount
points but immediately drops it again, only to re-grab it when it reaches the
next mount point.  The result is that the filename computed is not always
consisent, and the file may never have had that name. (This is unlikely, but
still possible.)

Fix this by grabbing the vfsmount_lock for the whole duration of
__d_path().

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: John Johansen <jjohansen@suse.de>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 13:06:13 -04:00
Miklos Szeredi
8837abcab3 nfsd: rename MAY_ flags
Rename nfsd_permission() specific MAY_* flags to NFSD_MAY_* to make it
clear, that these are not used outside nfsd, and to avoid name and
number space conflicts with the VFS.

[comment from hch: rename MAY_READ, MAY_WRITE and MAY_EXEC as well]

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:50 -04:00
NeilBrown
599eb3046a knfsd: nfsd: Handle ERESTARTSYS from syscalls.
OCFS2 can return -ERESTARTSYS from write requests (and possibly
elsewhere) if there is a signal pending.

If nfsd is shutdown (by sending a signal to each thread) while there
is still an IO load from the client, each thread could handle one last
request with a signal pending.  This can result in -ERESTARTSYS
which is not understood by nfserrno() and so is reflected back to
the client as nfserr_io aka -EIO.  This is wrong.

Instead, interpret ERESTARTSYS to mean "try again later" by returning
nfserr_jukebox.  The client will resend and - if the server is
restarted - the write will (hopefully) be successful and everyone will
be happy.

 The symptom that I narrowed down to this was:
    copy a large file via NFS to an OCFS2 filesystem, and restart
    the nfs server during the copy.
    The 'cp' might get an -EIO, and the file will be corrupted -
    presumably holes in the middle where writes appeared to fail.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:50 -04:00
Neil Brown
c7d106c90e nfsd: fix race in nfsd_nrthreads()
We need the nfsd_mutex before accessing nfsd_serv->sv_nrthreads or we
can't even guarantee nfsd_serv will still be there.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:50 -04:00
Jeff Layton
abd1ec4efd lockd: close potential race with rapid lockd_up/lockd_down cycle
If lockd_down is called very rapidly after lockd_up returns, then
there is a slim chance that lockd() will never be called. kthread()
will return before calling the function, so we'll end up never
actually calling the cleanup functions for the thread.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:50 -04:00
Jeff Layton
a75c5d01e4 sunrpc: remove sv_kill_signal field from svc_serv struct
Since we no longer make any distinction between shutdown signals with
nfsd, then it becomes easier to just standardize on a particular signal
to use to bring it down (SIGINT, in this case).

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:49 -04:00
Jeff Layton
9867d76ca1 knfsd: convert knfsd to kthread API
This patch is rather large, but I couldn't figure out a way to break it
up that would remain bisectable. It does several things:

- change svc_thread_fn typedef to better match what kthread_create expects
- change svc_pool_map_set_cpumask to be more kthread friendly. Make it
  take a task arg and and get rid of the "oldmask"
- have svc_set_num_threads call kthread_create directly
- eliminate __svc_create_thread

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:49 -04:00
Jeff Layton
e096bbc648 knfsd: remove special handling for SIGHUP
The special handling for SIGHUP in knfsd is a holdover from much
earlier versions of Linux where reloading the export table was
more expensive. That facility is not really needed anymore and
to my knowledge, is seldom-used.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:49 -04:00
Jeff Layton
3dd98a3bcc knfsd: clean up nfsd filesystem interfaces
Several of the nfsd filesystem interfaces allow changes to parameters
that don't have any effect on a running nfsd service. They are only ever
checked when nfsd is started. This patch fixes it so that changes to
those procfiles return -EBUSY if nfsd is already running to make it
clear that changes on the fly don't work.

The patch should also close some relatively harmless races between
changing the info in those interfaces and starting nfsd, since these
variables are being moved under the protection of the nfsd_mutex.

Finally, the nfsv4recoverydir file always returns -EINVAL if read. This
patch fixes it to return the recoverydir path as expected.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:49 -04:00
Neil Brown
bedbdd8bad knfsd: Replace lock_kernel with a mutex for nfsd thread startup/shutdown locking.
This removes the BKL from the RPC service creation codepath. The BKL
really isn't adequate for this job since some of this info needs
protection across sleeps.

Also, add some comments to try and clarify how the locking should work
and to make it clear that the BKL isn't necessary as long as there is
adequate locking between tasks when touching the svc_serv fields.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:49 -04:00
Benny Halevy
13b1867cac nfsd: make nfs4xdr WRITEMEM safe against zero count
WRITEMEM zeroes the last word in the destination buffer
for padding purposes, but this must not be done if
no bytes are to be copied, as it would result
in zeroing of the word right before the array.

The current implementation works since it's always called
with non zero nbytes or it follows an encoding of the
string (or opaque) length which, if equal to zero,
can be overwritten with zero.

Nevertheless, it seems safer to check for this case.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:48 -04:00
J. Bruce Fields
3b12cd9862 nfsd: add dprintk of compound return
We already print each operation of the compound when debugging is turned
on; printing the result could also help with remote debugging.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23 13:02:48 -04:00
Denis V. Lunev
f9f48ec72b [patch 4/4] flock: remove unused fields from file_lock_operations
fl_insert and fl_remove are not used right now in the kernel. Remove them.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 11:52:30 -04:00
Marcin Slusarz
694a1764d6 [patch 3/4] vfs: fix ERR_PTR abuse in generic_readlink
generic_readlink calls ERR_PTR for negative and positive values
(vfs_readlink returns length of "link"), but it should not
(not an errno) and does not need to.

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 11:52:30 -04:00
Jan Engelhardt
20d4fdc1a7 [patch 2/4] fs: make struct file arg to d_path const
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 11:52:30 -04:00
Jan Blunck
c8e7f449b2 [patch 1/4] vfs: path_{get,put}() cleanups
Here are some more places where path_{get,put}() can be used instead of
dput()/mntput() pair.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 11:52:29 -04:00
Michael Kerrisk
c70f844174 [patch for 2.6.26 4/4] vfs: utimensat(): fix write access check for futimens()
The POSIX.1 draft spec for futimens()/utimensat() says:

        Only a process with the effective user ID equal to the
        user ID of the file, *or with write access to the file*,
        or with appropriate privileges may use futimens() or
        utimensat() with a null pointer as the times argument
        or with both tv_nsec fields set to the special value
        UTIME_NOW.

The important piece here is "with write access to the file", and
this matters for futimens(), which deals with an argument that
is a file descriptor referring to the file whose timestamps are
being updated,  The standard is saying that the "writability"
check is based on the file permissions, not the access mode with
which the file is opened.  (This behavior is consistent with the
semantics of FreeBSD's futimes().)  However, Linux is currently
doing the latter -- futimens(fd, times) is a library
function implemented as

       utimensat(fd, NULL, times, 0)

and within the utimensat() implementation we have the code:

                f = fget(dfd);  // dfd is 'fd'
                ...
                if (f) {
                        if (!(f->f_mode & FMODE_WRITE))
                                goto mnt_drop_write_and_out;

The check should instead be based on the file permissions.

Thanks to Miklos for pointing out how to do this check.
Miklos also pointed out a simplification that could be
made to my first version of this patch, since the checks
for the pathname and file descriptor cases can now be
conflated.

Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 08:43:52 -04:00
Michael Kerrisk
4cca92264e [patch for 2.6.26 3/4] vfs: utimensat(): fix error checking for {UTIME_NOW,UTIME_OMIT} case
The POSIX.1 draft spec for utimensat() says:

    Only a process with the effective user ID equal to the
    user ID of the file or with appropriate privileges may use
    futimens() or utimensat() with a non-null times argument
    that does not have both tv_nsec fields set to UTIME_NOW
    and does not have both tv_nsec fields set to UTIME_OMIT.

If this condition is violated, then the error EPERM should result.
However, the current implementation does not generate EPERM if
one tv_nsec field is UTIME_NOW while the other is UTIME_OMIT.
It should give this error for that case.

This patch:

a) Repairs that problem.
b) Removes the now unneeded nsec_special() helper function.
c) Adds some comments to explain the checks that are being
   performed.

Thanks to Miklos, who provided comments on the previous iteration
of this patch.  As a result, this version is a little simpler and
and its logic is better structured.

Miklos suggested an alternative idea, migrating the
is_owner_or_cap() checks into fs/attr.c:inode_change_ok() via
the use of an ATTR_OWNER_CHECK flag.  Maybe we could do that
later, but for now I've gone with this version, which is
IMO simpler, and can be more easily read as being correct.

Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 08:43:04 -04:00
Michael Kerrisk
94c70b9ba7 [patch for 2.6.26 1/4] vfs: utimensat(): ignore tv_sec if tv_nsec == UTIME_OMIT or UTIME_NOW
The POSIX.1 draft spec for utimensat() says that if a times[n].tv_nsec
field is UTIME_OMIT or UTIME_NOW, then the value in the corresponding
tv_sec field is ignored.  See the last sentence of this para, from
the spec:

    If the tv_nsec field of a timespec structure has
    the special value UTIME_NOW, the file's relevant
    timestamp shall be set to the greatest value
    supported by the file system that is not greater than
    the current time. If the tv_nsec field has the
    special value UTIME_OMIT, the file's relevant
    timestamp shall not be changed. In either case,
    the tv_sec field shall be ignored.

However the current Linux implementation requires the tv_sec value to be
zero (or the EINVAL error results). This requirement should be removed.

Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 08:43:04 -04:00
Michael Kerrisk
12fd0d3088 [patch for 2.6.26 2/4] vfs: utimensat(): be consistent with utime() for immutable and append-only files
This patch fixes utimensat() to make its behavior consistent
with that of utime()/utimes() when dealing with files marked
immutable and append-only.

The current utimensat() implementation also returns EPERM if
'times' is non-NULL and the tv_nsec fields are both UTIME_NOW.
For consistency, the

(times != NULL && times[0].tv_nsec == UTIME_NOW &&
                  times[1].tv_nsec == UTIME_NOW)

case should be treated like the traditional utimes() case where
'times' is NULL.  That is, the call should succeed for a file
marked append-only and should give the error EACCES if the file
is marked as immutable.

The simple way to do this is to set 'times' to NULL
if (times[0].tv_nsec == UTIME_NOW && times[1].tv_nsec == UTIME_NOW).

This is also the natural approach, since POSIX.1 semantics consider the
times == {{x, UTIME_NOW}, {y, UTIME_NOW}}
to be exactly equivalent to the case for
times == NULL.

(Thanks to Miklos for pointing this out.)

Patch 3 in this series relies on the simplification provided
by this patch.

Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 08:43:03 -04:00
Al Viro
fe6e9c1f25 [PATCH] fix cgroup-inflicted breakage in block_dev.c
devcgroup_inode_permission() expects MAY_FOO, not FMODE_FOO; kindly
keep your misdesign consistent if you positively have to inflict it
on the kernel.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 08:30:55 -04:00