The object store limit needs to be updated after writing,
and this can be done provided the corresponding object has already
been initialized. Current object initialization is done asynchrously,
which introduce a race if a file is opened, then immediately followed
by a writing, the initialization may have not completed, the code will
reach the ASSERT in fscache_submit_exclusive_op() to cause kernel
bug.
Tested-by: Milosz Tanski <milosz@adfin.com>
Signed-off-by: Yunchuan Wen <yunchuanwen@ubuntukylin.com>
Signed-off-by: Min Chen <minchen@ubuntukylin.com>
Signed-off-by: Li Wang <liwang@ubuntukylin.com>
Synchronize object->store_limit[_l] with new inode->i_size after file writing.
Tested-by: Milosz Tanski <milosz@adfin.com>
Signed-off-by: Yunchuan Wen <yunchuanwen@ubuntukylin.com>
Signed-off-by: Min Chen <minchen@ubuntukylin.com>
Signed-off-by: Li Wang <liwang@ubuntukylin.com>
Add an interface to explicitly synchronize object->store_limit[_l]
with inode->i_size
Tested-by: Milosz Tanski <milosz@adfin.com>
Signed-off-by: Yunchuan Wen <yunchuanwen@ubuntukylin.com>
Signed-off-by: Min Chen <minchen@ubuntukylin.com>
Signed-off-by: Li Wang <liwang@ubuntukylin.com>
This is racy--we do not know whather d_parent has changed out from
underneath us because i_mutex is not held on the source inode's directory.
Also, taking this reference is useless.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Yan, Zheng <zheng.z.yan@intel.com>
Do not assume that r_old_dentry implies that r_old_dentry_dir is also
true. Separate out the ref cleanup and make the debugs dump behave when
it is NULL.
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Yan, Zheng <zheng.z.yan@intel.com>
The fsync(dirfd) only covers namespace operations, not inode updates.
We do not need to cover setattr variants or O_TRUNC.
Reported-by: Al Viro <viro@xeniv.linux.org.uk>
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Yan, Zheng <zheng.z.yan@intel.com>
This is just old_dir; no reason to abuse the dcache pointers.
Reported-by: Al Viro <viro.zeniv.linux.org.uk>
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Yan, Zheng <zheng.z.yan@intel.com>
If readdir 'frag' is adjusted, readdir 'offset' should be reset.
Otherwise some dentries may be lost when readdir and fragmenting
directory happen at the some.
Another way to fix this issue is let MDS adjust readdir 'frag'.
The code that handles MDS reply reset the readdir 'offset' if
the readdir reply is different than the requested one.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
When changing readdir postion, fi->next_offset should be set to 0
if the new postion is not in the first dirfrag.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Comparing offset with inode->i_sb->s_maxbytes doesn't make sense for
directory. For a fragmented directory, offset (frag_t, off) can be
larger than inode->i_sb->s_maxbytes.
At the very beginning of ceph_dir_llseek(), local variable old_offset
is initialized to parameter offset. This doesn't make sense neither.
Old_offset should be ceph_make_fpos(fi->frag, fi->next_offset).
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Pull vfs fixes from Al Viro:
"Switch mnt_hash to hlist, turning the races between __lookup_mnt() and
hash modifications into false negatives from __lookup_mnt() (instead
of hangs)"
On the false negatives from __lookup_mnt():
"The *only* thing we care about is not getting stuck in __lookup_mnt().
If it misses an entry because something in front of it just got moved
around, etc, we are fine. We'll notice that mount_lock mismatch and
that'll be it"
* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
switch mnt_hash to hlist
don't bother with propagate_mnt() unless the target is shared
keep shadowed vfsmounts together
resizable namespace.c hashes
Use cmpxchg() to atomically set i_flags instead of clearing out the
S_IMMUTABLE, S_APPEND, etc. flags and then setting them from the
EXT4_IMMUTABLE_FL, EXT4_APPEND_FL flags, since this opens up a race
where an immutable file has the immutable flag cleared for a brief
window of time.
Reported-by: John Sullivan <jsrhbz@kanargh.force9.co.uk>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fixes RCU bug - walking through hlist is safe in face of element moves,
since it's self-terminating. Cyclic lists are not - if we end up jumping
to another hash chain, we'll loop infinitely without ever hitting the
original list head.
[fix for dumb braino folded]
Spotted by: Max Kellermann <mk@cm4all.com>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If the dest_mnt is not shared, propagate_mnt() does nothing -
there's no mounts to propagate to and thus no copies to create.
Might as well don't bother calling it in that case.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch allocation to alloc_large_system_hash()
* make sizes overridable by boot parameters (mhash_entries=, mphash_entries=)
* switch mountpoint_hashtable from list_head to hlist_head
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Commit c74a3bdd9b ("ocfs2: add clustername to cluster connection") is
trying to strlcpy a string which was explicitly passed as NULL in the
very same patch, triggering a NULL ptr deref.
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: strlcpy (lib/string.c:388 lib/string.c:151)
CPU: 19 PID: 19426 Comm: trinity-c19 Tainted: G W 3.14.0-rc7-next-20140325-sasha-00014-g9476368-dirty #274
RIP: strlcpy (lib/string.c:388 lib/string.c:151)
Call Trace:
ocfs2_cluster_connect (fs/ocfs2/stackglue.c:350)
ocfs2_cluster_connect_agnostic (fs/ocfs2/stackglue.c:396)
user_dlm_register (fs/ocfs2/dlmfs/userdlm.c:679)
dlmfs_mkdir (fs/ocfs2/dlmfs/dlmfs.c:503)
vfs_mkdir (fs/namei.c:3467)
SyS_mkdirat (fs/namei.c:3488 fs/namei.c:3472)
tracesys (arch/x86/kernel/entry_64.S:749)
akpm: this patch probably disables the feature. A temporary thing to
avoid triviel oopses.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently we allocated anon_inode_inode in anon_inodefs_mount. This is
somewhat fragile as if that function ever gets called again, it will
overwrite anon_inode_inode pointer. So move the initialization of
anon_inode_inode to anon_inode_init().
Signed-off-by: Jan Kara <jack@suse.cz>
[ Further simplified on suggestion from Dave Jones ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The previous commit removed the register_filesystem() call and the
associated error handling, but left the label for the error path that no
longer exists. Remove that too.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
anon_inodefs filesystem is a kernel internal filesystem userspace
shouldn't mess with. Remove registration of it so userspace cannot
even try to mount it (which would fail anyway because the filesystem is
MS_NOUSER).
This fixes an oops triggered by trinity when it tried mounting
anon_inodefs which overwrote anon_inode_inode pointer while other CPU
has been in anon_inode_getfile() between ihold() and d_instantiate().
Thus effectively creating dentry pointing to an inode without holding a
reference to it.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull nfsd fix frm Bruce Fields:
"J R Okajima sent this early and I was just slow to pass it along,
apologies. Fortunately it's a simple fix"
* 'nfsd-next' of git://linux-nfs.org/~bfields/linux:
nfsd: fix lost nfserrno() call in nfsd_setattr()
We can get false negative from __lookup_mnt() if an unrelated vfsmount
gets moved. In that case legitimize_mnt() is guaranteed to fail,
and we will fall back to non-RCU walk... unless we end up running
into a hard error on a filesystem object we wouldn't have reached
if not for that false negative. IOW, delaying that check until
the end of pathname resolution is wrong - we should recheck right
after we attempt to cross the mountpoint. We don't need to recheck
unless we see d_mountpoint() being true - in that case even if
we have just raced with mount/umount, we can simply go on as if
we'd come at the moment when the sucker wasn't a mountpoint; if we
run into a hard error as the result, it was a legitimate outcome.
__lookup_mnt() returning NULL is different in that respect, since
it might've happened due to operation on completely unrelated
mountpoint.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In all callchains leading to prepend_name(), the value left in *buflen
is eventually discarded unused if prepend_name() has returned a negative.
So we are free to do what prepend() does, and subtract from *buflen
*before* checking for underflow (which turns into checking the sign
of subtraction result, of course).
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Commit bd2a31d522 ("get rid of fget_light()") introduced the
__fdget_pos() function, which returns the resulting file pointer and
fdput flags combined in an 'unsigned long'. However, it also changed the
behavior to return files with FMODE_PATH set, which shouldn't happen
because read(), write(), lseek(), etc. aren't allowed on such files.
This commit restores the old behavior.
This regression actually had no effect on read() and write() since
FMODE_READ and FMODE_WRITE are not set on file descriptors opened with
O_PATH, but it did cause lseek() on a file descriptor opened with O_PATH
to fail with ESPIPE rather than EBADF.
Signed-off-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Commit 9c225f2655 ("vfs: atomic f_pos accesses as per POSIX") changed
several system calls to use fdget_pos() instead of fdget(), but missed
sys_llseek(). Fix it.
Signed-off-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull CIFS fixes from Steve French:
"A fix for the problem which Al spotted in cifs_writev and a followup
(noticed when fixing CVE-2014-0069) patch to ensure that cifs never
sends more than the smb frame length over the socket (as we saw with
that cifs_iovec_write problem that Jeff fixed last month)"
* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
cifs: mask off top byte in get_rfc1002_length()
cifs: sanity check length of data to send before sending
CIFS: Fix wrong pos argument of cifs_find_lock_conflict
Merge misc fixes from Andrew Morton:
"Nine fixes"
* emailed patches from Andrew Morton akpm@linux-foundation.org>:
cris: convert ffs from an object-like macro to a function-like macro
hfsplus: add HFSX subfolder count support
tools/testing/selftests/ipc/msgque.c: handle msgget failure return correctly
MAINTAINERS: blackfin: add git repository
revert "kallsyms: fix absolute addresses for kASLR"
mm/Kconfig: fix URL for zsmalloc benchmark
fs/proc/base.c: fix GPF in /proc/$PID/map_files
mm/compaction: break out of loop on !PageBuddy in isolate_freepages_block
mm: fix GFP_THISNODE callers and clarify
Adds support for HFSX 'HasFolderCount' flag and a corresponding
'folderCount' field in folder records. (For reference see
HFS_FOLDERCOUNT and kHFSHasFolderCountBit/kHFSHasFolderCountMask in
Apple's source code.)
Ignoring subfolder count leads to fs errors found by Mac:
...
Checking catalog hierarchy.
HasFolderCount flag needs to be set (id = 105)
(It should be 0x10 instead of 0)
Incorrect folder count in a directory (id = 2)
(It should be 7 instead of 6)
...
Steps to reproduce:
Format with "newfs_hfs -s /dev/diskXXX".
Mount in Linux.
Create a new directory in root.
Unmount.
Run "fsck_hfs /dev/diskXXX".
The patch handles directory creation, deletion, and rename.
Signed-off-by: Sergei Antonov <saproj@gmail.com>
Reviewed-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The expected logic of proc_map_files_get_link() is either to return 0
and initialize 'path' or return an error and leave 'path' uninitialized.
By the time dname_to_vma_addr() returns 0 the corresponding vma may have
already be gone. In this case the path is not initialized but the
return value is still 0. This results in 'general protection fault'
inside d_path().
Steps to reproduce:
CONFIG_CHECKPOINT_RESTORE=y
fd = open(...);
while (1) {
mmap(fd, ...);
munmap(fd, ...);
}
ls -la /proc/$PID/map_files
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=68991
Signed-off-by: Artem Fetishev <artem_fetishev@epam.com>
Signed-off-by: Aleksandr Terekhov <aleksandr_terekhov@epam.com>
Reported-by: <wiebittewas@gmail.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs fixes from Al Viro.
Clean up file table accesses (get rid of fget_light() in favor of the
fdget() interface), add proper file position locking.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
get rid of fget_light()
sockfd_lookup_light(): switch to fdget^W^Waway from fget_light
vfs: atomic f_pos accesses as per POSIX
ocfs2 syncs the wrong range...
instead of returning the flags by reference, we can just have the
low-level primitive return those in lower bits of unsigned long,
with struct file * derived from the rest.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Our write() system call has always been atomic in the sense that you get
the expected thread-safe contiguous write, but we haven't actually
guaranteed that concurrent writes are serialized wrt f_pos accesses, so
threads (or processes) that share a file descriptor and use "write()"
concurrently would quite likely overwrite each others data.
This violates POSIX.1-2008/SUSv4 Section XSI 2.9.7 that says:
"2.9.7 Thread Interactions with Regular File Operations
All of the following functions shall be atomic with respect to each
other in the effects specified in POSIX.1-2008 when they operate on
regular files or symbolic links: [...]"
and one of the effects is the file position update.
This unprotected file position behavior is not new behavior, and nobody
has ever cared. Until now. Yongzhi Pan reported unexpected behavior to
Michael Kerrisk that was due to this.
This resolves the issue with a f_pos-specific lock that is taken by
read/write/lseek on file descriptors that may be shared across threads
or processes.
Reported-by: Yongzhi Pan <panyongzhi@gmail.com>
Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Highlights include:
- Fix another nfs4_sequence corruptor in RELEASE_LOCKOWNER
- Fix an Oopsable delegation callback race
- Fix another bad stateid infinite loop
- Fail the data server I/O is the stateid represents a lost lock
- Fix an Oopsable sunrpc trace event
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Merge tag 'nfs-for-3.14-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- Fix another nfs4_sequence corruptor in RELEASE_LOCKOWNER
- Fix an Oopsable delegation callback race
- Fix another bad stateid infinite loop
- Fail the data server I/O is the stateid represents a lost lock
- Fix an Oopsable sunrpc trace event"
* tag 'nfs-for-3.14-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
SUNRPC: Fix oops when trace sunrpc_task events in nfs client
NFSv4: Fail the truncate() if the lock/open stateid is invalid
NFSv4.1 Fail data server I/O if stateid represents a lost lock
NFSv4: Fix the return value of nfs4_select_rw_stateid
NFSv4: nfs4_stateid_is_current should return 'true' for an invalid stateid
NFS: Fix a delegation callback race
NFSv4: Fix another nfs4_sequence corruptor
Pull block fixes from Jens Axboe:
"Small collection of fixes for 3.14-rc. It contains:
- Three minor update to blk-mq from Christoph.
- Reduce number of unaligned (< 4kb) in-flight writes on mtip32xx to
two. From Micron.
- Make the blk-mq CPU notify spinlock raw, since it can't be a
sleeper spinlock on RT. From Mike Galbraith.
- Drop now bogus BUG_ON() for bio iteration with blk integrity. From
Nic Bellinger.
- Properly propagate the SYNC flag on requests. From Shaohua"
* 'for-linus' of git://git.kernel.dk/linux-block:
blk-mq: add REQ_SYNC early
rt,blk,mq: Make blk_mq_cpu_notify_lock a raw spinlock
bio-integrity: Drop bio_integrity_verify BUG_ON in post bip->bip_iter world
blk-mq: support partial I/O completions
blk-mq: merge blk_mq_insert_request and blk_mq_run_request
blk-mq: remove blk_mq_alloc_rq
mtip32xx: Reduce the number of unaligned writes to 2
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>
Current implementation of HFS+ driver has small issue with remount
option. Namely, for example, you are unable to remount from RO mode
into RW mode by means of command "mount -o remount,rw /dev/loop0
/mnt/hfsplus". Trying to execute sequence of commands results in an
error message:
mount /dev/loop0 /mnt/hfsplus
mount -o remount,ro /dev/loop0 /mnt/hfsplus
mount -o remount,rw /dev/loop0 /mnt/hfsplus
mount: you must specify the filesystem type
mount -t hfsplus -o remount,rw /dev/loop0 /mnt/hfsplus
mount: /mnt/hfsplus not mounted or bad option
The reason of such issue is failure of mount syscall:
mount("/dev/loop0", "/mnt/hfsplus", 0x2282a60, MS_MGC_VAL|MS_REMOUNT, NULL) = -1 EINVAL (Invalid argument)
Namely, hfsplus_parse_options_remount() method receives empty "input"
argument and return false in such case. As a result, hfsplus_remount()
returns -EINVAL error code.
This patch fixes the issue by means of return true for the case of empty
"input" argument in hfsplus_parse_options_remount() method.
Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Global quota files are accessed from different nodes. Thus we cannot
cache offset of quota structure in the quota file after we drop our node
reference count to it because after that moment quota structure may be
freed and reallocated elsewhere by a different node resulting in
corruption of quota file.
Fix the problem by clearing dq_off when we are releasing dquot structure.
We also remove the DB_READ_B handling because it is useless -
DQ_ACTIVE_B is set iff DQ_READ_B is set.
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit bf6bddf192 ("mm: introduce compaction and migration for
ballooned pages") introduces page_count(page) into memory compaction
which dereferences page->first_page if PageTail(page).
This results in a very rare NULL pointer dereference on the
aforementioned page_count(page). Indeed, anything that does
compound_head(), including page_count() is susceptible to racing with
prep_compound_page() and seeing a NULL or dangling page->first_page
pointer.
This patch uses Andrea's implementation of compound_trans_head() that
deals with such a race and makes it the default compound_head()
implementation. This includes a read memory barrier that ensures that
if PageTail(head) is true that we return a head page that is neither
NULL nor dangling. The patch then adds a store memory barrier to
prep_compound_page() to ensure page->first_page is set.
This is the safest way to ensure we see the head page that we are
expecting, PageTail(page) is already in the unlikely() path and the
memory barriers are unfortunately required.
Hugetlbfs is the exception, we don't enforce a store memory barrier
during init since no race is possible.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Holger Kiehl <Holger.Kiehl@dwd.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
Here is a single sysfs fix for 3.14-rc5. It fixes a reported problem
with the namespace code in sysfs.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull sysfs fix from Greg KH:
"Here is a single sysfs fix for 3.14-rc5. It fixes a reported problem
with the namespace code in sysfs"
* tag 'driver-core-3.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
sysfs: fix namespace refcnt leak
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>
The rfc1002 length actually includes a type byte, which we aren't
masking off. In most cases, it's not a problem since the
RFC1002_SESSION_MESSAGE type is 0, but when doing a RFC1002 session
establishment, the type is non-zero and that throws off the returned
length.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Pull filesystem fixes from Jan Kara:
"Notification, writeback, udf, quota fixes
The notification patches are (with one exception) a fallout of my
fsnotify rework which went into -rc1 (I've extented LTP to cover these
cornercases to avoid similar breakage in future).
The UDF patch is a nasty data corruption Al has recently reported,
the revert of the writeback patch is due to possibility of violating
sync(2) guarantees, and a quota bug can lead to corruption of quota
files in ocfs2"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fsnotify: Allocate overflow events with proper type
fanotify: Handle overflow in case of permission events
fsnotify: Fix detection whether overflow event is queued
Revert "writeback: do not sync data dirtied after sync start"
quota: Fix race between dqput() and dquot_scan_active()
udf: Fix data corruption on file type conversion
inotify: Fix reporting of cookies for inotify events
As mount() and kill_sb() is not a one-to-one match, we shoudn't get
ns refcnt unconditionally in sysfs_mount(), and instead we should
get the refcnt only when kernfs_mount() allocated a new superblock.
v2:
- Changed the name of the new argument, suggested by Tejun.
- Made the argument optional, suggested by Tejun.
v3:
- Make the new argument as second-to-last arg, suggested by Tejun.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
---
fs/kernfs/mount.c | 8 +++++++-
fs/sysfs/mount.c | 5 +++--
include/linux/kernfs.h | 9 +++++----
3 files changed, 15 insertions(+), 7 deletions(-)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 7053aee26a "fsnotify: do not share events between notification
groups" used overflow event statically allocated in a group with the
size of the generic notification event. This causes problems because
some code looks at type specific parts of event structure and gets
confused by a random data it sees there and causes crashes.
Fix the problem by allocating overflow event with type corresponding to
the group type so code cannot get confused.
Signed-off-by: Jan Kara <jack@suse.cz>
If the event queue overflows when we are handling permission event, we
will never get response from userspace. So we must avoid waiting for it.
Change fsnotify_add_notify_event() to return whether overflow has
happened so that we can detect it in fanotify_handle_event() and act
accordingly.
Signed-off-by: Jan Kara <jack@suse.cz>
