There is no guarantee that the strings in the nfs_cache_array will be
NULL-terminated. In the event that we end up hitting a readdir loop, we
need to ensure that we pass the warning message the length of the
string.
Reported-by: Lachlan McIlroy <lmcilroy@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If we interrupt the nfs4_wait_for_completion_rpc_task() call in
nfs4_run_open_task(), then we don't prevent the RPC call from
completing. So freeing up the opendata->f_attr.mdsthreshold
in the error path in _nfs4_do_open() leads to a use-after-free
when the XDR decoder tries to decode the mdsthreshold information
from the server.
Fixes: 82be417aa3 (NFSv4.1 cache mdsthreshold values on OPEN)
Tested-by: Steve Dickson <SteveD@redhat.com>
Cc: stable@vger.kernel.org # 3.5+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If a timeout or a signal interrupts the NFSv4 trunking discovery
SETCLIENTID_CONFIRM call, then we don't know whether or not the
server has changed the callback identifier on us.
Assume that it did, and schedule a 'path down' recovery...
Tested-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
NFSv4.0 clients use the SETCLIENTID operation to inform NFS servers
how to contact a client's callback service. If a server cannot
contact a client's callback service, that server will not delegate
to that client, which results in a performance loss.
Our client advertises "rdma" as the callback netid when the forward
channel is "rdma". But our client always starts only "tcp" and
"tcp6" callback services.
Instead of advertising the forward channel netid, advertise "tcp"
or "tcp6" as the callback netid, based on the value of the
clientaddr mount option, since those are what our client currently
supports.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=69171
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Security labels go with each directory entry, thus they are always
stored in the page cache, not in the head buffer. The length of the
reply that goes in head[0] should not have changed to support
NFSv4.2 labels.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If a file is sillyrenamed, then the generic vfs_unlink code will skip
emitting fsnotify events for it.
This patch has the sillyrename code do that instead.
In truth this is a little bit odd since we aren't actually removing the
dentry per-se, but renaming it. Still, this is probably the right thing
to do since it's what userland apps expect to see when an unlink()
occurs or some file is renamed on top of the dentry.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that nfs_rename uses the async infrastructure, we can remove this.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
There isn't much sense in maintaining two separate versions of rename
code. Convert nfs_rename to use the asynchronous rename infrastructure
that nfs_sillyrename uses, and emulate synchronous behavior by having
the task just wait on the reply.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
...and move the prototype for nfs_sillyrename to internal.h.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The async rename code is currently "polluted" with some parts that are
really just for sillyrenames. Add a new "complete" operation vector to
the nfs_renamedata to separate out the stuff that just needs to be done
for a sillyrename.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the open stateid could not be recovered, or the file locks were lost,
then we should fail the truncate() operation altogether.
Reported-by: Andy Adamson <andros@netapp.com>
Link: http://lkml.kernel.org/r/1393954269-3974-1-git-send-email-andros@netapp.com
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
In commit 5521abfdcf (NFSv4: Resend the READ/WRITE RPC call
if a stateid change causes an error), we overloaded the return value of
nfs4_select_rw_stateid() to cause it to return -EWOULDBLOCK if an RPC
call is outstanding that would cause the NFSv4 lock or open stateid
to change.
That is all redundant when we actually copy the stateid used in the
read/write RPC call that failed, and check that against the current
stateid. It is doubly so, when we consider that in the NFSv4.1 case,
we also set the stateid's seqid to the special value '0', which means
'match the current valid stateid'.
Reported-by: Andy Adamson <andros@netapp.com>
Link: http://lkml.kernel.org/r/1393954269-3974-1-git-send-email-andros@netapp.com
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When nfs4_set_rw_stateid() can fails by returning EIO to indicate that
the stateid is completely invalid, then it makes no sense to have it
trigger a retry of the READ or WRITE operation. Instead, we should just
have it fall through and attempt a recovery.
This fixes an infinite loop in which the client keeps replaying the same
bad stateid back to the server.
Reported-by: Andy Adamson <andros@netapp.com>
Link: http://lkml.kernel.org/r/1393954269-3974-1-git-send-email-andros@netapp.com
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The clean-up in commit 36281caa83 ended up removing a NULL pointer check
that is needed in order to prevent an Oops in
nfs_async_inode_return_delegation().
Reported-by: "Yan, Zheng" <zheng.z.yan@intel.com>
Link: http://lkml.kernel.org/r/5313E9F6.2020405@intel.com
Fixes: 36281caa83 (NFSv4: Further clean-ups of delegation stateid validation)
Cc: stable@vger.kernel.org # 3.4+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs4_release_lockowner needs to set the rpc_message reply to point to
the nfs4_sequence_res in order to avoid another Oopsable situation
in nfs41_assign_slot.
Fixes: fbd4bfd1d9 (NFS: Add nfs4_sequence calls for RELEASE_LOCKOWNER)
Cc: stable@vger.kernel.org # 3.12+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
RFC3530 and RFC5661 both prescribe that the 'opaque' field of the
open stateid returned by new OPEN/OPEN_DOWNGRADE/CLOSE calls for
the same file and open owner should match.
If this is not the case, assume that the open state has been lost,
and that we need to recover it.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The stateid and state->flags should be updated atomically under
protection of the state->seqlock.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the server returns a completely new layout stateid in response to our
LAYOUTGET, then make sure to free any existing layout segments.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the filehandles match, but the igrab() fails, or the layout is
freed before we can get it, then just return NULL.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It is not sufficient to compare filehandles when we receive a layout
recall from the server; we also need to check that the layout stateids
match.
Reported-by: shaobingqing <shaobingqing@bwstor.com.cn>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Subtraction of signed integers does not have well defined wraparound
semantics in the C99 standard. In order to be wraparound-safe, we
have to use unsigned subtraction, and then cast the result.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We need to use the same net namespace that was used to resolve
the hostname and sockaddr arguments.
Fixes: 32e62b7c3e (NFS: Add nfs4_update_server)
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Try to detect 'ls -l' by having nfs_getattr() look at whether or not
there is an opendir() file descriptor for the parent directory.
If so, then assume that we want to force use of readdirplus in order
to avoid the multiple GETATTR calls over the wire.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Commit aa9c266962 (NFS: Client implementation of Labeled-NFS) introduces
a performance regression. When nfs_zap_caches_locked is called, it sets
the NFS_INO_INVALID_LABEL flag irrespectively of whether or not the
NFS server supports security labels. Since that flag is never cleared,
it means that all calls to nfs_revalidate_inode() will now trigger
an on-the-wire GETATTR call.
This patch ensures that we never set the NFS_INO_INVALID_LABEL unless the
server advertises support for labeled NFS.
It also causes nfs_setsecurity() to clear NFS_INO_INVALID_LABEL when it
has successfully set the security label for the inode.
Finally it gets rid of the NFS_INO_INVALID_LABEL cruft from nfs_update_inode,
which has nothing to do with labeled NFS.
Reported-by: Neil Brown <neilb@suse.de>
Cc: stable@vger.kernel.org # 3.11+
Tested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs3_proc_setacls is used internally by the NFSv3 create operations
to set the acl after the file has been created. If the operation
fails because the server doesn't support acls, then it must return '0',
not -EOPNOTSUPP.
Reported-by: Russell King <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/20140201010328.GI15937@n2100.arm.linux.org.uk
Cc: Christoph Hellwig <hch@lst.de>
Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
There may still be timers active on the session waitqueues. Make sure
that we kill them before freeing the memory.
Cc: stable@vger.kernel.org # 3.12+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs41_wake_and_assign_slot() relies on the task->tk_msg.rpc_argp and
task->tk_msg.rpc_resp always pointing to the session sequence arguments.
nfs4_proc_open_confirm tries to pull a fast one by reusing the open
sequence structure, thus causing corruption of the NFSv4 slot table.
Cc: stable@vger.kernel.org # 3.12+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs3_get_acl() tries to skip posix equivalent ACLs, but misinterprets
the return value of posix_acl_equiv_mode(). Fix it.
This is a regression introduced by
"nfs: use generic posix ACL infrastructure for v3 Posix ACLs"
CC: Christoph Hellwig <hch@infradead.org>
CC: linux-nfs@vger.kernel.org
CC: linux-fsdevel@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Highlights:
- Fix several races in nfs_revalidate_mapping
- NFSv4.1 slot leakage in the pNFS files driver
- Stable fix for a slot leak in nfs40_sequence_done
- Don't reject NFSv4 servers that support ACLs with only ALLOW aces
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=B7f0
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.14-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights:
- Fix several races in nfs_revalidate_mapping
- NFSv4.1 slot leakage in the pNFS files driver
- Stable fix for a slot leak in nfs40_sequence_done
- Don't reject NFSv4 servers that support ACLs with only ALLOW aces"
* tag 'nfs-for-3.14-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
nfs: initialize the ACL support bits to zero.
NFSv4.1: Cleanup
NFSv4.1: Clean up nfs41_sequence_done
NFSv4: Fix a slot leak in nfs40_sequence_done
NFSv4.1 free slot before resending I/O to MDS
nfs: add memory barriers around NFS_INO_INVALID_DATA and NFS_INO_INVALIDATING
NFS: Fix races in nfs_revalidate_mapping
sunrpc: turn warn_gssd() log message into a dprintk()
NFS: fix the handling of NFS_INO_INVALID_DATA flag in nfs_revalidate_mapping
nfs: handle servers that support only ALLOW ACE type.
Avoid returning incorrect acl mask attributes when the server doesn't
support ACLs.
Signed-off-by: Malahal Naineni <malahal@us.ibm.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull core block IO changes from Jens Axboe:
"The major piece in here is the immutable bio_ve series from Kent, the
rest is fairly minor. It was supposed to go in last round, but
various issues pushed it to this release instead. The pull request
contains:
- Various smaller blk-mq fixes from different folks. Nothing major
here, just minor fixes and cleanups.
- Fix for a memory leak in the error path in the block ioctl code
from Christian Engelmayer.
- Header export fix from CaiZhiyong.
- Finally the immutable biovec changes from Kent Overstreet. This
enables some nice future work on making arbitrarily sized bios
possible, and splitting more efficient. Related fixes to immutable
bio_vecs:
- dm-cache immutable fixup from Mike Snitzer.
- btrfs immutable fixup from Muthu Kumar.
- bio-integrity fix from Nic Bellinger, which is also going to stable"
* 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits)
xtensa: fixup simdisk driver to work with immutable bio_vecs
block/blk-mq-cpu.c: use hotcpu_notifier()
blk-mq: for_each_* macro correctness
block: Fix memory leak in rw_copy_check_uvector() handling
bio-integrity: Fix bio_integrity_verify segment start bug
block: remove unrelated header files and export symbol
blk-mq: uses page->list incorrectly
blk-mq: use __smp_call_function_single directly
btrfs: fix missing increment of bi_remaining
Revert "block: Warn and free bio if bi_end_io is not set"
block: Warn and free bio if bi_end_io is not set
blk-mq: fix initializing request's start time
block: blk-mq: don't export blk_mq_free_queue()
block: blk-mq: make blk_sync_queue support mq
block: blk-mq: support draining mq queue
dm cache: increment bi_remaining when bi_end_io is restored
block: fixup for generic bio chaining
block: Really silence spurious compiler warnings
block: Silence spurious compiler warnings
block: Kill bio_pair_split()
...
Chris Mason reported a NULL pointer derefernence in generic_getxattr()
that was due to sb->s_xattr being NULL.
The reason is that the nfs #ifdef's for ACL support were misplaced, and
the nfs3 inode operations had the xattr operation pointers set up, even
though xattrs were not actually supported. As a result, the xattr code
was being called without the infrastructure having been set up.
Move the #ifdef's appropriately.
Reported-and-tested-by: Chris Mason <clm@fb.com>
Acked-by: Al Viro viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the test for res->sr_slot == NULL out of the nfs41_sequence_free_slot
helper and into the main function for efficiency.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The check for whether or not we sent an RPC call in nfs40_sequence_done
is insufficient to decide whether or not we are holding a session slot,
and thus should not be used to decide when to free that slot.
This patch replaces the RPC_WAS_SENT() test with the correct test for
whether or not slot == NULL.
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org # 3.12+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fix a dynamic session slot leak where a slot is preallocated and I/O is
resent through the MDS.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the setting of NFS_INO_INVALIDATING gets reordered to before the
clearing of NFS_INO_INVALID_DATA, then another task may hit a race
window where both appear to be clear, even though the inode's pages are
still in need of invalidation. Fix this by adding the appropriate memory
barriers.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Highlights include:
- Stable fix for an infinite loop in RPC state machine
- Stable fix for a use after free situation in the NFSv4 trunking discovery
- Stable fix for error handling in the NFSv4 trunking discovery
- Stable fix for the page write update code
- Stable fix for the NFSv4.1 mount time security negotiation
- Stable fix for the NFSv4 open code.
- O_DIRECT locking fixes
- fix an Oops in the pnfs file commit code
- RPC layer needs finer grained handling of connection errors
- More RPC GSS upcall fixes
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=abfY
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
- stable fix for an infinite loop in RPC state machine
- stable fix for a use after free situation in the NFSv4 trunking discovery
- stable fix for error handling in the NFSv4 trunking discovery
- stable fix for the page write update code
- stable fix for the NFSv4.1 mount time security negotiation
- stable fix for the NFSv4 open code.
- O_DIRECT locking fixes
- fix an Oops in the pnfs file commit code
- RPC layer needs finer grained handling of connection errors
- more RPC GSS upcall fixes"
* tag 'nfs-for-3.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (30 commits)
pnfs: Proper delay for NFS4ERR_RECALLCONFLICT in layout_get_done
pnfs: fix BUG in filelayout_recover_commit_reqs
nfs4: fix discover_server_trunking use after free
NFSv4.1: Handle errors correctly in nfs41_walk_client_list
nfs: always make sure page is up-to-date before extending a write to cover the entire page
nfs: page cache invalidation for dio
nfs: take i_mutex during direct I/O reads
nfs: merge nfs_direct_write into nfs_file_direct_write
nfs: merge nfs_direct_read into nfs_file_direct_read
nfs: increment i_dio_count for reads, too
nfs: defer inode_dio_done call until size update is done
nfs: fix size updates for aio writes
nfs4.1: properly handle ENOTSUP in SECINFO_NO_NAME
NFSv4.1: Fix a race in nfs4_write_inode
NFSv4.1: Don't trust attributes if a pNFS LAYOUTCOMMIT is outstanding
point to the right include file in a comment (left over from a9004abc3)
NFS: dprintk() should not print negative fileids and inode numbers
nfs: fix dead code of ipv6_addr_scope
sunrpc: Fix infinite loop in RPC state machine
SUNRPC: Add tracepoint for socket errors
...
Commit d529ef83c3 (NFS: fix the handling
of NFS_INO_INVALID_DATA flag in nfs_revalidate_mapping) introduces
a potential race, since it doesn't test the value of nfsi->cache_validity
and set the bitlock in nfsi->flags atomically.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Jeff Layton <jlayton@redhat.com>
The original printk() made sense when the GSSAPI codepaths were called
only when sec=krb5* was explicitly requested. Now however, in many cases
the nfs client will try to acquire GSSAPI credentials by default, even
when it's not requested.
Since we don't have a great mechanism to distinguish between the two
cases, just turn the pr_warn into a dprintk instead. With this change we
can also get rid of the ratelimiting.
We do need to keep the EXPORT_SYMBOL(gssd_running) in place since
auth_gss.ko needs it and sunrpc.ko provides it. We can however,
eliminate the gssd_running call in the nfs code since that's a bit of a
layering violation.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
There is a possible race in how the nfs_invalidate_mapping function is
handled. Currently, we go and invalidate the pages in the file and then
clear NFS_INO_INVALID_DATA.
The problem is that it's possible for a stale page to creep into the
mapping after the page was invalidated (i.e., via readahead). If another
writer comes along and sets the flag after that happens but before
invalidate_inode_pages2 returns then we could clear the flag
without the cache having been properly invalidated.
So, we must clear the flag first and then invalidate the pages. Doing
this however, opens another race:
It's possible to have two concurrent read() calls that end up in
nfs_revalidate_mapping at the same time. The first one clears the
NFS_INO_INVALID_DATA flag and then goes to call nfs_invalidate_mapping.
Just before calling that though, the other task races in, checks the
flag and finds it cleared. At that point, it trusts that the mapping is
good and gets the lock on the page, allowing the read() to be satisfied
from the cache even though the data is no longer valid.
These effects are easily manifested by running diotest3 from the LTP
test suite on NFS. That program does a series of DIO writes and buffered
reads. The operations are serialized and page-aligned but the existing
code fails the test since it occasionally allows a read to come out of
the cache incorrectly. While mixing direct and buffered I/O isn't
recommended, I believe it's possible to hit this in other ways that just
use buffered I/O, though that situation is much harder to reproduce.
The problem is that the checking/clearing of that flag and the
invalidation of the mapping really need to be atomic. Fix this by
serializing concurrent invalidations with a bitlock.
At the same time, we also need to allow other places that check
NFS_INO_INVALID_DATA to check whether we might be in the middle of
invalidating the file, so fix up a couple of places that do that
to look for the new NFS_INO_INVALIDATING flag.
Doing this requires us to be careful not to set the bitlock
unnecessarily, so this code only does that if it believes it will
be doing an invalidation.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Currently we support ACLs if the NFS server file system supports both
ALLOW and DENY ACE types. This patch makes the Linux client work with
ACLs even if the server supports only 'ALLOW' ACE type.
Signed-off-by: Malahal Naineni <malahal@us.ibm.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This causes a small behaviour change in that we don't bother to set
ACLs on file creation if the mode bit can express the access permissions
fully, and thus behaving identical to local filesystems.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
