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40,643 commits

Author SHA1 Message Date
Al Viro
c8ce76e3c6 use ->d_seq to get coherency between ->d_inode and ->d_flags
[ Upstream commit a528aca7f3 ]

Games with ordering and barriers are way too brittle.  Just
bump ->d_seq before and after updating ->d_inode and ->d_flags
type bits, so that verifying ->d_seq would guarantee they are
coherent.

Cc: stable@vger.kernel.org # v3.13+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:20 -05:00
Peter Zijlstra
4950beba62 seqcount: Rename write_seqcount_barrier()
[ Upstream commit a7c6f571ff ]

I'll shortly be introducing another seqcount primitive that's useful
to provide ordering semantics and would like to use the
write_seqcount_barrier() name for that.

Seeing how there's only one user of the current primitive, lets rename
it to invalidate, as that appears what its doing.

While there, employ lockdep_assert_held() instead of
assert_spin_locked() to not generate debug code for regular kernels.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: ktkhai@parallels.com
Cc: rostedt@goodmis.org
Cc: juri.lelli@gmail.com
Cc: pang.xunlei@linaro.org
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: wanpeng.li@linux.intel.com
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: umgwanakikbuti@gmail.com
Link: http://lkml.kernel.org/r/20150611124743.279926217@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:20 -05:00
Yadan Fan
092bb6bd43 Fix cifs_uniqueid_to_ino_t() function for s390x
[ Upstream commit 1ee9f4bd1a ]

This issue is caused by commit 02323db17e ("cifs: fix
cifs_uniqueid_to_ino_t not to ever return 0"), when BITS_PER_LONG
is 64 on s390x, the corresponding cifs_uniqueid_to_ino_t()
function will cast 64-bit fileid to 32-bit by using (ino_t)fileid,
because ino_t (typdefed __kernel_ino_t) is int type.

It's defined in arch/s390/include/uapi/asm/posix_types.h

    #ifndef __s390x__

    typedef unsigned long   __kernel_ino_t;
    ...
    #else /* __s390x__ */

    typedef unsigned int    __kernel_ino_t;

So the #ifdef condition is wrong for s390x, we can just still use
one cifs_uniqueid_to_ino_t() function with comparing sizeof(ino_t)
and sizeof(u64) to choose the correct execution accordingly.

Signed-off-by: Yadan Fan <ydfan@suse.com>
CC: stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:17 -05:00
Pavel Shilovsky
78b821d76e CIFS: Fix SMB2+ interim response processing for read requests
[ Upstream commit 6cc3b24235 ]

For interim responses we only need to parse a header and update
a number credits. Now it is done for all SMB2+ command except
SMB2_READ which is wrong. Fix this by adding such processing.

Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Tested-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:16 -05:00
Justin Maggard
94a7d752e4 cifs: fix out-of-bounds access in lease parsing
[ Upstream commit deb7deff2f ]

When opening a file, SMB2_open() attempts to parse the lease state from the
SMB2 CREATE Response.  However, the parsing code was not careful to ensure
that the create contexts are not empty or invalid, which can lead to out-
of-bounds memory access.  This can be seen easily by trying
to read a file from a OSX 10.11 SMB3 server.  Here is sample crash output:

BUG: unable to handle kernel paging request at ffff8800a1a77cc6
IP: [<ffffffff8828a734>] SMB2_open+0x804/0x960
PGD 8f77067 PUD 0
Oops: 0000 [#1] SMP
Modules linked in:
CPU: 3 PID: 2876 Comm: cp Not tainted 4.5.0-rc3.x86_64.1+ #14
Hardware name: NETGEAR ReadyNAS 314          /ReadyNAS 314          , BIOS 4.6.5 10/11/2012
task: ffff880073cdc080 ti: ffff88005b31c000 task.ti: ffff88005b31c000
RIP: 0010:[<ffffffff8828a734>]  [<ffffffff8828a734>] SMB2_open+0x804/0x960
RSP: 0018:ffff88005b31fa08  EFLAGS: 00010282
RAX: 0000000000000015 RBX: 0000000000000000 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff88007eb8c8b0
RBP: ffff88005b31fad8 R08: 666666203d206363 R09: 6131613030383866
R10: 3030383866666666 R11: 00000000000002b0 R12: ffff8800660fd800
R13: ffff8800a1a77cc2 R14: 00000000424d53fe R15: ffff88005f5a28c0
FS:  00007f7c8a2897c0(0000) GS:ffff88007eb80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff8800a1a77cc6 CR3: 000000005b281000 CR4: 00000000000006e0
Stack:
 ffff88005b31fa70 ffffffff88278789 00000000000001d3 ffff88005f5a2a80
 ffffffff00000003 ffff88005d029d00 ffff88006fde05a0 0000000000000000
 ffff88005b31fc78 ffff88006fde0780 ffff88005b31fb2f 0000000100000fe0
Call Trace:
 [<ffffffff88278789>] ? cifsConvertToUTF16+0x159/0x2d0
 [<ffffffff8828cf68>] smb2_open_file+0x98/0x210
 [<ffffffff8811e80c>] ? __kmalloc+0x1c/0xe0
 [<ffffffff882685f4>] cifs_open+0x2a4/0x720
 [<ffffffff88122cef>] do_dentry_open+0x1ff/0x310
 [<ffffffff88268350>] ? cifsFileInfo_get+0x30/0x30
 [<ffffffff88123d92>] vfs_open+0x52/0x60
 [<ffffffff88131dd0>] path_openat+0x170/0xf70
 [<ffffffff88097d48>] ? remove_wait_queue+0x48/0x50
 [<ffffffff88133a29>] do_filp_open+0x79/0xd0
 [<ffffffff8813f2ca>] ? __alloc_fd+0x3a/0x170
 [<ffffffff881240c4>] do_sys_open+0x114/0x1e0
 [<ffffffff881241a9>] SyS_open+0x19/0x20
 [<ffffffff8896e257>] entry_SYSCALL_64_fastpath+0x12/0x6a
Code: 4d 8d 6c 07 04 31 c0 4c 89 ee e8 47 6f e5 ff 31 c9 41 89 ce 44 89 f1 48 c7 c7 28 b1 bd 88 31 c0 49 01 cd 4c 89 ee e8 2b 6f e5 ff <45> 0f b7 75 04 48 c7 c7 31 b1 bd 88 31 c0 4d 01 ee 4c 89 f6 e8
RIP  [<ffffffff8828a734>] SMB2_open+0x804/0x960
 RSP <ffff88005b31fa08>
CR2: ffff8800a1a77cc6
---[ end trace d9f69ba64feee469 ]---

Signed-off-by: Justin Maggard <jmaggard@netgear.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:16 -05:00
Al Viro
9b77cd137f namei: ->d_inode of a pinned dentry is stable only for positives
[ Upstream commit d4565649b6 ]

both do_last() and walk_component() risk picking a NULL inode out
of dentry about to become positive, *then* checking its flags and
seeing that it's not negative anymore and using (already stale by
then) value they'd fetched earlier.  Usually ends up oopsing soon
after that...

Cc: stable@vger.kernel.org # v3.13+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:13 -05:00
Al Viro
3960cde3e3 do_last(): don't let a bogus return value from ->open() et.al. to confuse us
[ Upstream commit c80567c82a ]

... into returning a positive to path_openat(), which would interpret that
as "symlink had been encountered" and proceed to corrupt memory, etc.
It can only happen due to a bug in some ->open() instance or in some LSM
hook, etc., so we report any such event *and* make sure it doesn't trick
us into further unpleasantness.

Cc: stable@vger.kernel.org # v3.6+, at least
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:12 -05:00
Mikulas Patocka
6cb69cb284 hpfs: don't truncate the file when delete fails
[ Upstream commit b6853f78e7 ]

The delete opration can allocate additional space on the HPFS filesystem
due to btree split. The HPFS driver checks in advance if there is
available space, so that it won't corrupt the btree if we run out of space
during splitting.

If there is not enough available space, the HPFS driver attempted to
truncate the file, but this results in a deadlock since the commit
7dd29d8d86 ("HPFS: Introduce a global mutex
and lock it on every callback from VFS").

This patch removes the code that tries to truncate the file and -ENOSPC is
returned instead. If the user hits -ENOSPC on delete, he should try to
delete other files (that are stored in a leaf btree node), so that the
delete operation will make some space for deleting the file stored in
non-leaf btree node.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: stable@vger.kernel.org	# 2.6.39+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:12 -05:00
David Woodhouse
49f76896f8 Fix directory hardlinks from deleted directories
[ Upstream commit be629c62a6 ]

When a directory is deleted, we don't take too much care about killing off
all the dirents that belong to it — on the basis that on remount, the scan
will conclude that the directory is dead anyway.

This doesn't work though, when the deleted directory contained a child
directory which was moved *out*. In the early stages of the fs build
we can then end up with an apparent hard link, with the child directory
appearing both in its true location, and as a child of the original
directory which are this stage of the mount process we don't *yet* know
is defunct.

To resolve this, take out the early special-casing of the "directories
shall not have hard links" rule in jffs2_build_inode_pass1(), and let the
normal nlink processing happen for directories as well as other inodes.

Then later in the build process we can set ic->pino_nlink to the parent
inode#, as is required for directories during normal operaton, instead
of the nlink. And complain only *then* about hard links which are still
in evidence even after killing off all the unreachable paths.

Reported-by: Liu Song <liu.song11@zte.com.cn>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:07 -05:00
David Woodhouse
e0dae728bf jffs2: Fix page lock / f->sem deadlock
[ Upstream commit 49e91e7079 ]

With this fix, all code paths should now be obtaining the page lock before
f->sem.

Reported-by: Szabó Tamás <sztomi89@gmail.com>
Tested-by: Thomas Betker <thomas.betker@rohde-schwarz.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:07 -05:00
Thomas Betker
74d11976ff Revert "jffs2: Fix lock acquisition order bug in jffs2_write_begin"
[ Upstream commit 157078f64b ]

This reverts commit 5ffd3412ae
("jffs2: Fix lock acquisition order bug in jffs2_write_begin").

The commit modified jffs2_write_begin() to remove a deadlock with
jffs2_garbage_collect_live(), but this introduced new deadlocks found
by multiple users. page_lock() actually has to be called before
mutex_lock(&c->alloc_sem) or mutex_lock(&f->sem) because
jffs2_write_end() and jffs2_readpage() are called with the page locked,
and they acquire c->alloc_sem and f->sem, resp.

In other words, the lock order in jffs2_write_begin() was correct, and
it is the jffs2_garbage_collect_live() path that has to be changed.

Revert the commit to get rid of the new deadlocks, and to clear the way
for a better fix of the original deadlock.

Reported-by: Deng Chao <deng.chao1@zte.com.cn>
Reported-by: Ming Liu <liu.ming50@gmail.com>
Reported-by: wangzaiwei <wangzaiwei@top-vision.cn>
Signed-off-by: Thomas Betker <thomas.betker@rohde-schwarz.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-09 13:15:06 -05:00
Benjamin Coddington
038d8248fc NFSv4: Fix a dentry leak on alias use
[ Upstream commit d9dfd8d741 ]

In the case where d_add_unique() finds an appropriate alias to use it will
have already incremented the reference count.  An additional dget() to swap
the open context's dentry is unnecessary and will leak a reference.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: 275bb30786 ("NFSv4: Move dentry instantiation into the NFSv4-...")
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-07 12:27:25 -05:00
Jan Kara
62adae8f26 ext4: fix crashes in dioread_nolock mode
[ Upstream commit 74dae42785 ]

Competing overwrite DIO in dioread_nolock mode will just overwrite
pointer to io_end in the inode. This may result in data corruption or
extent conversion happening from IO completion interrupt because we
don't properly set buffer_defer_completion() when unlocked DIO races
with locked DIO to unwritten extent.

Since unlocked DIO doesn't need io_end for anything, just avoid
allocating it and corrupting pointer from inode for locked DIO.
A cleaner fix would be to avoid these games with io_end pointer from the
inode but that requires more intrusive changes so we leave that for
later.

Cc: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-04 10:25:45 -05:00
Eryu Guan
a285eee1ce ext4: don't read blocks from disk after extents being swapped
[ Upstream commit bcff24887d ]

I notice ext4/307 fails occasionally on ppc64 host, reporting md5
checksum mismatch after moving data from original file to donor file.

The reason is that move_extent_per_page() calls __block_write_begin()
and block_commit_write() to write saved data from original inode blocks
to donor inode blocks, but __block_write_begin() not only maps buffer
heads but also reads block content from disk if the size is not block
size aligned.  At this time the physical block number in mapped buffer
head is pointing to the donor file not the original file, and that
results in reading wrong data to page, which get written to disk in
following block_commit_write call.

This also can be reproduced by the following script on 1k block size ext4
on x86_64 host:

    mnt=/mnt/ext4
    donorfile=$mnt/donor
    testfile=$mnt/testfile
    e4compact=~/xfstests/src/e4compact

    rm -f $donorfile $testfile

    # reserve space for donor file, written by 0xaa and sync to disk to
    # avoid EBUSY on EXT4_IOC_MOVE_EXT
    xfs_io -fc "pwrite -S 0xaa 0 1m" -c "fsync" $donorfile

    # create test file written by 0xbb
    xfs_io -fc "pwrite -S 0xbb 0 1023" -c "fsync" $testfile

    # compute initial md5sum
    md5sum $testfile | tee md5sum.txt
    # drop cache, force e4compact to read data from disk
    echo 3 > /proc/sys/vm/drop_caches

    # test defrag
    echo "$testfile" | $e4compact -i -v -f $donorfile
    # check md5sum
    md5sum -c md5sum.txt

Fix it by creating & mapping buffer heads only but not reading blocks
from disk, because all the data in page is guaranteed to be up-to-date
in mext_page_mkuptodate().

Cc: stable@vger.kernel.org
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-04 10:25:42 -05:00
Insu Yun
9d7679794e ext4: fix potential integer overflow
[ Upstream commit 46901760b4 ]

Since sizeof(ext_new_group_data) > sizeof(ext_new_flex_group_data),
integer overflow could be happened.
Therefore, need to fix integer overflow sanitization.

Cc: stable@vger.kernel.org
Signed-off-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-04 10:25:42 -05:00
David Sterba
3a68deb667 btrfs: properly set the termination value of ctx->pos in readdir
[ Upstream commit bc4ef7592f ]

The value of ctx->pos in the last readdir call is supposed to be set to
INT_MAX due to 32bit compatibility, unless 'pos' is intentially set to a
larger value, then it's LLONG_MAX.

There's a report from PaX SIZE_OVERFLOW plugin that "ctx->pos++"
overflows (https://forums.grsecurity.net/viewtopic.php?f=1&t=4284), on a
64bit arch, where the value is 0x7fffffffffffffff ie. LLONG_MAX before
the increment.

We can get to that situation like that:

* emit all regular readdir entries
* still in the same call to readdir, bump the last pos to INT_MAX
* next call to readdir will not emit any entries, but will reach the
  bump code again, finds pos to be INT_MAX and sets it to LLONG_MAX

Normally this is not a problem, but if we call readdir again, we'll find
'pos' set to LLONG_MAX and the unconditional increment will overflow.

The report from Victor at
(http://thread.gmane.org/gmane.comp.file-systems.btrfs/49500) with debugging
print shows that pattern:

 Overflow: e
 Overflow: 7fffffff
 Overflow: 7fffffffffffffff
 PAX: size overflow detected in function btrfs_real_readdir
   fs/btrfs/inode.c:5760 cicus.935_282 max, count: 9, decl: pos; num: 0;
   context: dir_context;
 CPU: 0 PID: 2630 Comm: polkitd Not tainted 4.2.3-grsec #1
 Hardware name: Gigabyte Technology Co., Ltd. H81ND2H/H81ND2H, BIOS F3 08/11/2015
  ffffffff81901608 0000000000000000 ffffffff819015e6 ffffc90004973d48
  ffffffff81742f0f 0000000000000007 ffffffff81901608 ffffc90004973d78
  ffffffff811cb706 0000000000000000 ffff8800d47359e0 ffffc90004973ed8
 Call Trace:
  [<ffffffff81742f0f>] dump_stack+0x4c/0x7f
  [<ffffffff811cb706>] report_size_overflow+0x36/0x40
  [<ffffffff812ef0bc>] btrfs_real_readdir+0x69c/0x6d0
  [<ffffffff811dafc8>] iterate_dir+0xa8/0x150
  [<ffffffff811e6d8d>] ? __fget_light+0x2d/0x70
  [<ffffffff811dba3a>] SyS_getdents+0xba/0x1c0
 Overflow: 1a
  [<ffffffff811db070>] ? iterate_dir+0x150/0x150
  [<ffffffff81749b69>] entry_SYSCALL_64_fastpath+0x12/0x83

The jump from 7fffffff to 7fffffffffffffff happens when new dir entries
are not yet synced and are processed from the delayed list. Then the code
could go to the bump section again even though it might not emit any new
dir entries from the delayed list.

The fix avoids entering the "bump" section again once we've finished
emitting the entries, both for synced and delayed entries.

References: https://forums.grsecurity.net/viewtopic.php?f=1&t=4284
Reported-by: Victor <services@swwu.com>
CC: stable@vger.kernel.org
Signed-off-by: David Sterba <dsterba@suse.com>
Tested-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-04 10:25:42 -05:00
Anton Protopopov
4f55047bff cifs: fix erroneous return value
[ Upstream commit 4b550af519 ]

The setup_ntlmv2_rsp() function may return positive value ENOMEM instead
of -ENOMEM in case of kmalloc failure.

Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-03-04 10:25:41 -05:00
Herton R. Krzesinski
38bdf7e3fb pty: make sure super_block is still valid in final /dev/tty close
[ Upstream commit 1f55c718c2 ]

Considering current pty code and multiple devpts instances, it's possible
to umount a devpts file system while a program still has /dev/tty opened
pointing to a previosuly closed pty pair in that instance. In the case all
ptmx and pts/N files are closed, umount can be done. If the program closes
/dev/tty after umount is done, devpts_kill_index will use now an invalid
super_block, which was already destroyed in the umount operation after
running ->kill_sb. This is another "use after free" type of issue, but now
related to the allocated super_block instance.

To avoid the problem (warning at ida_remove and potential crashes) for
this specific case, I added two functions in devpts which grabs additional
references to the super_block, which pty code now uses so it makes sure
the super block structure is still valid until pty shutdown is done.
I also moved the additional inode references to the same functions, which
also covered similar case with inode being freed before /dev/tty final
close/shutdown.

Signed-off-by: Herton R. Krzesinski <herton@redhat.com>
Cc: stable@vger.kernel.org # 2.6.29+
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-28 00:09:50 -05:00
Filipe Manana
79179a6845 Btrfs: fix hang on extent buffer lock caused by the inode_paths ioctl
[ Upstream commit 0c0fe3b0fa ]

While doing some tests I ran into an hang on an extent buffer's rwlock
that produced the following trace:

[39389.800012] NMI watchdog: BUG: soft lockup - CPU#15 stuck for 22s! [fdm-stress:32166]
[39389.800016] NMI watchdog: BUG: soft lockup - CPU#14 stuck for 22s! [fdm-stress:32165]
[39389.800016] Modules linked in: btrfs dm_mod ppdev xor sha256_generic hmac raid6_pq drbg ansi_cprng aesni_intel i2c_piix4 acpi_cpufreq aes_x86_64 ablk_helper tpm_tis parport_pc i2c_core sg cryptd evdev psmouse lrw tpm parport gf128mul serio_raw pcspkr glue_helper processor button loop autofs4 ext4 crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring crc32c_intel scsi_mod e1000 virtio floppy [last unloaded: btrfs]
[39389.800016] irq event stamp: 0
[39389.800016] hardirqs last  enabled at (0): [<          (null)>]           (null)
[39389.800016] hardirqs last disabled at (0): [<ffffffff8104e58d>] copy_process+0x638/0x1a35
[39389.800016] softirqs last  enabled at (0): [<ffffffff8104e58d>] copy_process+0x638/0x1a35
[39389.800016] softirqs last disabled at (0): [<          (null)>]           (null)
[39389.800016] CPU: 14 PID: 32165 Comm: fdm-stress Not tainted 4.4.0-rc6-btrfs-next-18+ #1
[39389.800016] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[39389.800016] task: ffff880175b1ca40 ti: ffff8800a185c000 task.ti: ffff8800a185c000
[39389.800016] RIP: 0010:[<ffffffff810902af>]  [<ffffffff810902af>] queued_spin_lock_slowpath+0x57/0x158
[39389.800016] RSP: 0018:ffff8800a185fb80  EFLAGS: 00000202
[39389.800016] RAX: 0000000000000101 RBX: ffff8801710c4e9c RCX: 0000000000000101
[39389.800016] RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000001
[39389.800016] RBP: ffff8800a185fb98 R08: 0000000000000001 R09: 0000000000000000
[39389.800016] R10: ffff8800a185fb68 R11: 6db6db6db6db6db7 R12: ffff8801710c4e98
[39389.800016] R13: ffff880175b1ca40 R14: ffff8800a185fc10 R15: ffff880175b1ca40
[39389.800016] FS:  00007f6d37fff700(0000) GS:ffff8802be9c0000(0000) knlGS:0000000000000000
[39389.800016] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[39389.800016] CR2: 00007f6d300019b8 CR3: 0000000037c93000 CR4: 00000000001406e0
[39389.800016] Stack:
[39389.800016]  ffff8801710c4e98 ffff8801710c4e98 ffff880175b1ca40 ffff8800a185fbb0
[39389.800016]  ffffffff81091e11 ffff8801710c4e98 ffff8800a185fbc8 ffffffff81091895
[39389.800016]  ffff8801710c4e98 ffff8800a185fbe8 ffffffff81486c5c ffffffffa067288c
[39389.800016] Call Trace:
[39389.800016]  [<ffffffff81091e11>] queued_read_lock_slowpath+0x46/0x60
[39389.800016]  [<ffffffff81091895>] do_raw_read_lock+0x3e/0x41
[39389.800016]  [<ffffffff81486c5c>] _raw_read_lock+0x3d/0x44
[39389.800016]  [<ffffffffa067288c>] ? btrfs_tree_read_lock+0x54/0x125 [btrfs]
[39389.800016]  [<ffffffffa067288c>] btrfs_tree_read_lock+0x54/0x125 [btrfs]
[39389.800016]  [<ffffffffa0622ced>] ? btrfs_find_item+0xa7/0xd2 [btrfs]
[39389.800016]  [<ffffffffa069363f>] btrfs_ref_to_path+0xd6/0x174 [btrfs]
[39389.800016]  [<ffffffffa0693730>] inode_to_path+0x53/0xa2 [btrfs]
[39389.800016]  [<ffffffffa0693e2e>] paths_from_inode+0x117/0x2ec [btrfs]
[39389.800016]  [<ffffffffa0670cff>] btrfs_ioctl+0xd5b/0x2793 [btrfs]
[39389.800016]  [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[39389.800016]  [<ffffffff81276727>] ? __this_cpu_preempt_check+0x13/0x15
[39389.800016]  [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[39389.800016]  [<ffffffff8118b3d4>] ? rcu_read_unlock+0x3e/0x5d
[39389.800016]  [<ffffffff811822f8>] do_vfs_ioctl+0x42b/0x4ea
[39389.800016]  [<ffffffff8118b4f3>] ? __fget_light+0x62/0x71
[39389.800016]  [<ffffffff8118240e>] SyS_ioctl+0x57/0x79
[39389.800016]  [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f
[39389.800016] Code: b9 01 01 00 00 f7 c6 00 ff ff ff 75 32 83 fe 01 89 ca 89 f0 0f 45 d7 f0 0f b1 13 39 f0 74 04 89 c6 eb e2 ff ca 0f 84 fa 00 00 00 <8b> 03 84 c0 74 04 f3 90 eb f6 66 c7 03 01 00 e9 e6 00 00 00 e8
[39389.800012] Modules linked in: btrfs dm_mod ppdev xor sha256_generic hmac raid6_pq drbg ansi_cprng aesni_intel i2c_piix4 acpi_cpufreq aes_x86_64 ablk_helper tpm_tis parport_pc i2c_core sg cryptd evdev psmouse lrw tpm parport gf128mul serio_raw pcspkr glue_helper processor button loop autofs4 ext4 crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring crc32c_intel scsi_mod e1000 virtio floppy [last unloaded: btrfs]
[39389.800012] irq event stamp: 0
[39389.800012] hardirqs last  enabled at (0): [<          (null)>]           (null)
[39389.800012] hardirqs last disabled at (0): [<ffffffff8104e58d>] copy_process+0x638/0x1a35
[39389.800012] softirqs last  enabled at (0): [<ffffffff8104e58d>] copy_process+0x638/0x1a35
[39389.800012] softirqs last disabled at (0): [<          (null)>]           (null)
[39389.800012] CPU: 15 PID: 32166 Comm: fdm-stress Tainted: G             L  4.4.0-rc6-btrfs-next-18+ #1
[39389.800012] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[39389.800012] task: ffff880179294380 ti: ffff880034a60000 task.ti: ffff880034a60000
[39389.800012] RIP: 0010:[<ffffffff81091e8d>]  [<ffffffff81091e8d>] queued_write_lock_slowpath+0x62/0x72
[39389.800012] RSP: 0018:ffff880034a639f0  EFLAGS: 00000206
[39389.800012] RAX: 0000000000000101 RBX: ffff8801710c4e98 RCX: 0000000000000000
[39389.800012] RDX: 00000000000000ff RSI: 0000000000000000 RDI: ffff8801710c4e9c
[39389.800012] RBP: ffff880034a639f8 R08: 0000000000000001 R09: 0000000000000000
[39389.800012] R10: ffff880034a639b0 R11: 0000000000001000 R12: ffff8801710c4e98
[39389.800012] R13: 0000000000000001 R14: ffff880172cbc000 R15: ffff8801710c4e00
[39389.800012] FS:  00007f6d377fe700(0000) GS:ffff8802be9e0000(0000) knlGS:0000000000000000
[39389.800012] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[39389.800012] CR2: 00007f6d3d3c1000 CR3: 0000000037c93000 CR4: 00000000001406e0
[39389.800012] Stack:
[39389.800012]  ffff8801710c4e98 ffff880034a63a10 ffffffff81091963 ffff8801710c4e98
[39389.800012]  ffff880034a63a30 ffffffff81486f1b ffffffffa0672cb3 ffff8801710c4e00
[39389.800012]  ffff880034a63a78 ffffffffa0672cb3 ffff8801710c4e00 ffff880034a63a58
[39389.800012] Call Trace:
[39389.800012]  [<ffffffff81091963>] do_raw_write_lock+0x72/0x8c
[39389.800012]  [<ffffffff81486f1b>] _raw_write_lock+0x3a/0x41
[39389.800012]  [<ffffffffa0672cb3>] ? btrfs_tree_lock+0x119/0x251 [btrfs]
[39389.800012]  [<ffffffffa0672cb3>] btrfs_tree_lock+0x119/0x251 [btrfs]
[39389.800012]  [<ffffffffa061aeba>] ? rcu_read_unlock+0x5b/0x5d [btrfs]
[39389.800012]  [<ffffffffa061ce13>] ? btrfs_root_node+0xda/0xe6 [btrfs]
[39389.800012]  [<ffffffffa061ce83>] btrfs_lock_root_node+0x22/0x42 [btrfs]
[39389.800012]  [<ffffffffa062046b>] btrfs_search_slot+0x1b8/0x758 [btrfs]
[39389.800012]  [<ffffffff810fc6b0>] ? time_hardirqs_on+0x15/0x28
[39389.800012]  [<ffffffffa06365db>] btrfs_lookup_inode+0x31/0x95 [btrfs]
[39389.800012]  [<ffffffff8108d62f>] ? trace_hardirqs_on+0xd/0xf
[39389.800012]  [<ffffffff8148482b>] ? mutex_lock_nested+0x397/0x3bc
[39389.800012]  [<ffffffffa068821b>] __btrfs_update_delayed_inode+0x59/0x1c0 [btrfs]
[39389.800012]  [<ffffffffa068858e>] __btrfs_commit_inode_delayed_items+0x194/0x5aa [btrfs]
[39389.800012]  [<ffffffff81486ab7>] ? _raw_spin_unlock+0x31/0x44
[39389.800012]  [<ffffffffa0688a48>] __btrfs_run_delayed_items+0xa4/0x15c [btrfs]
[39389.800012]  [<ffffffffa0688d62>] btrfs_run_delayed_items+0x11/0x13 [btrfs]
[39389.800012]  [<ffffffffa064048e>] btrfs_commit_transaction+0x234/0x96e [btrfs]
[39389.800012]  [<ffffffffa0618d10>] btrfs_sync_fs+0x145/0x1ad [btrfs]
[39389.800012]  [<ffffffffa0671176>] btrfs_ioctl+0x11d2/0x2793 [btrfs]
[39389.800012]  [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[39389.800012]  [<ffffffff81140261>] ? __might_fault+0x4c/0xa7
[39389.800012]  [<ffffffff81140261>] ? __might_fault+0x4c/0xa7
[39389.800012]  [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[39389.800012]  [<ffffffff8118b3d4>] ? rcu_read_unlock+0x3e/0x5d
[39389.800012]  [<ffffffff811822f8>] do_vfs_ioctl+0x42b/0x4ea
[39389.800012]  [<ffffffff8118b4f3>] ? __fget_light+0x62/0x71
[39389.800012]  [<ffffffff8118240e>] SyS_ioctl+0x57/0x79
[39389.800012]  [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f
[39389.800012] Code: f0 0f b1 13 85 c0 75 ef eb 2a f3 90 8a 03 84 c0 75 f8 f0 0f b0 13 84 c0 75 f0 ba ff 00 00 00 eb 0a f0 0f b1 13 ff c8 74 0b f3 90 <8b> 03 83 f8 01 75 f7 eb ed c6 43 04 00 5b 5d c3 0f 1f 44 00 00

This happens because in the code path executed by the inode_paths ioctl we
end up nesting two calls to read lock a leaf's rwlock when after the first
call to read_lock() and before the second call to read_lock(), another
task (running the delayed items as part of a transaction commit) has
already called write_lock() against the leaf's rwlock. This situation is
illustrated by the following diagram:

         Task A                       Task B

  btrfs_ref_to_path()               btrfs_commit_transaction()
    read_lock(&eb->lock);

                                      btrfs_run_delayed_items()
                                        __btrfs_commit_inode_delayed_items()
                                          __btrfs_update_delayed_inode()
                                            btrfs_lookup_inode()

                                              write_lock(&eb->lock);
                                                --> task waits for lock

    read_lock(&eb->lock);
    --> makes this task hang
        forever (and task B too
	of course)

So fix this by avoiding doing the nested read lock, which is easily
avoidable. This issue does not happen if task B calls write_lock() after
task A does the second call to read_lock(), however there does not seem
to exist anything in the documentation that mentions what is the expected
behaviour for recursive locking of rwlocks (leaving the idea that doing
so is not a good usage of rwlocks).

Also, as a side effect necessary for this fix, make sure we do not
needlessly read lock extent buffers when the input path has skip_locking
set (used when called from send).

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-28 00:09:41 -05:00
xuejiufei
ff5ecd2953 ocfs2/dlm: clear refmap bit of recovery lock while doing local recovery cleanup
[ Upstream commit c95a51807b ]

When recovery master down, dlm_do_local_recovery_cleanup() only remove
the $RECOVERY lock owned by dead node, but do not clear the refmap bit.
Which will make umount thread falling in dead loop migrating $RECOVERY
to the dead node.

Signed-off-by: xuejiufei <xuejiufei@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-15 15:45:36 -05:00
Trond Myklebust
9295dee2df pNFS/flexfiles: Fix an XDR encoding bug in layoutreturn
[ Upstream commit 082fa37d13 ]

We must not skip encoding the statistics, or the server will see an
XDR encoding error.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-15 15:45:19 -05:00
Tariq Saeed
b085ab71a7 ocfs2: NFS hangs in __ocfs2_cluster_lock due to race with ocfs2_unblock_lock
[ Upstream commit b1b1e15ef6 ]

NFS on a 2 node ocfs2 cluster each node exporting dir.  The lock causing
the hang is the global bit map inode lock.  Node 1 is master, has the
lock granted in PR mode; Node 2 is in the converting list (PR -> EX).
There are no holders of the lock on the master node so it should
downconvert to NL and grant EX to node 2 but that does not happen.
BLOCKED + QUEUED in lock res are set and it is on osb blocked list.
Threads are waiting in __ocfs2_cluster_lock on BLOCKED.  One thread
wants EX, rest want PR.  So it is as though the downconvert thread needs
to be kicked to complete the conv.

The hang is caused by an EX req coming into __ocfs2_cluster_lock on the
heels of a PR req after it sets BUSY (drops l_lock, releasing EX
thread), forcing the incoming EX to wait on BUSY without doing anything.
PR has called ocfs2_dlm_lock, which sets the node 1 lock from NL -> PR,
queues ast.

At this time, upconvert (PR ->EX) arrives from node 2, finds conflict
with node 1 lock in PR, so the lock res is put on dlm thread's dirty
listt.

After ret from ocf2_dlm_lock, PR thread now waits behind EX on BUSY till
awoken by ast.

Now it is dlm_thread that serially runs dlm_shuffle_lists, ast, bast, in
that order.  dlm_shuffle_lists ques a bast on behalf of node 2 (which
will be run by dlm_thread right after the ast).  ast does its part, sets
UPCONVERT_FINISHING, clears BUSY and wakes its waiters.  Next,
dlm_thread runs bast.  It sets BLOCKED and kicks dc thread.  dc thread
runs ocfs2_unblock_lock, but since UPCONVERT_FINISHING set, skips doing
anything and reques.

Inside of __ocfs2_cluster_lock, since EX has been waiting on BUSY ahead
of PR, it wakes up first, finds BLOCKED set and skips doing anything but
clearing UPCONVERT_FINISHING (which was actually "meant" for the PR
thread), and this time waits on BLOCKED.  Next, the PR thread comes out
of wait but since UPCONVERT_FINISHING is not set, it skips updating the
l_ro_holders and goes straight to wait on BLOCKED.  So there, we have a
hang! Threads in __ocfs2_cluster_lock wait on BLOCKED, lock res in osb
blocked list.  Only when dc thread is awoken, it will run
ocfs2_unblock_lock and things will unhang.

One way to fix this is to wake the dc thread on the flag after clearing
UPCONVERT_FINISHING

Orabug: 20933419
Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Eric Ren <zren@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-15 15:45:19 -05:00
Filipe Manana
e004a09725 Btrfs: fix deadlock running delayed iputs at transaction commit time
[ Upstream commit c2d6cb1636 ]

While running a stress test I ran into a deadlock when running the delayed
iputs at transaction time, which produced the following report and trace:

[  886.399989] =============================================
[  886.400871] [ INFO: possible recursive locking detected ]
[  886.401663] 4.4.0-rc6-btrfs-next-18+ #1 Not tainted
[  886.402384] ---------------------------------------------
[  886.403182] fio/8277 is trying to acquire lock:
[  886.403568]  (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs]
[  886.403568]
[  886.403568] but task is already holding lock:
[  886.403568]  (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs]
[  886.403568]
[  886.403568] other info that might help us debug this:
[  886.403568]  Possible unsafe locking scenario:
[  886.403568]
[  886.403568]        CPU0
[  886.403568]        ----
[  886.403568]   lock(&fs_info->delayed_iput_sem);
[  886.403568]   lock(&fs_info->delayed_iput_sem);
[  886.403568]
[  886.403568]  *** DEADLOCK ***
[  886.403568]
[  886.403568]  May be due to missing lock nesting notation
[  886.403568]
[  886.403568] 3 locks held by fio/8277:
[  886.403568]  #0:  (sb_writers#11){.+.+.+}, at: [<ffffffff81174c4c>] __sb_start_write+0x5f/0xb0
[  886.403568]  #1:  (&sb->s_type->i_mutex_key#15){+.+.+.}, at: [<ffffffffa054620d>] btrfs_file_write_iter+0x73/0x408 [btrfs]
[  886.403568]  #2:  (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs]
[  886.403568]
[  886.403568] stack backtrace:
[  886.403568] CPU: 6 PID: 8277 Comm: fio Not tainted 4.4.0-rc6-btrfs-next-18+ #1
[  886.403568] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[  886.403568]  0000000000000000 ffff88009f80f770 ffffffff8125d4fd ffffffff82af1fc0
[  886.403568]  ffff88009f80f830 ffffffff8108e5f9 0000000200000000 ffff88009fd92290
[  886.403568]  0000000000000000 ffffffff82af1fc0 ffffffff829cfb01 00042b216d008804
[  886.403568] Call Trace:
[  886.403568]  [<ffffffff8125d4fd>] dump_stack+0x4e/0x79
[  886.403568]  [<ffffffff8108e5f9>] __lock_acquire+0xd42/0xf0b
[  886.403568]  [<ffffffff810c22db>] ? __module_address+0xdf/0x108
[  886.403568]  [<ffffffff8108eb77>] lock_acquire+0x10d/0x194
[  886.403568]  [<ffffffff8108eb77>] ? lock_acquire+0x10d/0x194
[  886.403568]  [<ffffffffa0538823>] ? btrfs_run_delayed_iputs+0x36/0xbf [btrfs]
[  886.489542]  [<ffffffff8148556b>] down_read+0x3e/0x4d
[  886.489542]  [<ffffffffa0538823>] ? btrfs_run_delayed_iputs+0x36/0xbf [btrfs]
[  886.489542]  [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs]
[  886.489542]  [<ffffffffa0533953>] btrfs_commit_transaction+0x8f5/0x96e [btrfs]
[  886.489542]  [<ffffffffa0521d7a>] flush_space+0x435/0x44a [btrfs]
[  886.489542]  [<ffffffffa052218b>] ? reserve_metadata_bytes+0x26a/0x384 [btrfs]
[  886.489542]  [<ffffffffa05221ae>] reserve_metadata_bytes+0x28d/0x384 [btrfs]
[  886.489542]  [<ffffffffa052256c>] ? btrfs_block_rsv_refill+0x58/0x96 [btrfs]
[  886.489542]  [<ffffffffa0522584>] btrfs_block_rsv_refill+0x70/0x96 [btrfs]
[  886.489542]  [<ffffffffa053d747>] btrfs_evict_inode+0x394/0x55a [btrfs]
[  886.489542]  [<ffffffff81188e31>] evict+0xa7/0x15c
[  886.489542]  [<ffffffff81189878>] iput+0x1d3/0x266
[  886.489542]  [<ffffffffa053887c>] btrfs_run_delayed_iputs+0x8f/0xbf [btrfs]
[  886.489542]  [<ffffffffa0533953>] btrfs_commit_transaction+0x8f5/0x96e [btrfs]
[  886.489542]  [<ffffffff81085096>] ? signal_pending_state+0x31/0x31
[  886.489542]  [<ffffffffa0521191>] btrfs_alloc_data_chunk_ondemand+0x1d7/0x288 [btrfs]
[  886.489542]  [<ffffffffa0521282>] btrfs_check_data_free_space+0x40/0x59 [btrfs]
[  886.489542]  [<ffffffffa05228f5>] btrfs_delalloc_reserve_space+0x1e/0x4e [btrfs]
[  886.489542]  [<ffffffffa053620a>] btrfs_direct_IO+0x10c/0x27e [btrfs]
[  886.489542]  [<ffffffff8111d9a1>] generic_file_direct_write+0xb3/0x128
[  886.489542]  [<ffffffffa05463c3>] btrfs_file_write_iter+0x229/0x408 [btrfs]
[  886.489542]  [<ffffffff8108ae38>] ? __lock_is_held+0x38/0x50
[  886.489542]  [<ffffffff8117279e>] __vfs_write+0x7c/0xa5
[  886.489542]  [<ffffffff81172cda>] vfs_write+0xa0/0xe4
[  886.489542]  [<ffffffff811734cc>] SyS_write+0x50/0x7e
[  886.489542]  [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f
[ 1081.852335] INFO: task fio:8244 blocked for more than 120 seconds.
[ 1081.854348]       Not tainted 4.4.0-rc6-btrfs-next-18+ #1
[ 1081.857560] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1081.863227] fio        D ffff880213f9bb28     0  8244   8240 0x00000000
[ 1081.868719]  ffff880213f9bb28 00ffffff810fc6b0 ffffffff0000000a ffff88023ed55240
[ 1081.872499]  ffff880206b5d400 ffff880213f9c000 ffff88020a4d5318 ffff880206b5d400
[ 1081.876834]  ffffffff00000001 ffff880206b5d400 ffff880213f9bb40 ffffffff81482ba4
[ 1081.880782] Call Trace:
[ 1081.881793]  [<ffffffff81482ba4>] schedule+0x7f/0x97
[ 1081.883340]  [<ffffffff81485eb5>] rwsem_down_write_failed+0x2d5/0x325
[ 1081.895525]  [<ffffffff8108d48d>] ? trace_hardirqs_on_caller+0x16/0x1ab
[ 1081.897419]  [<ffffffff81269723>] call_rwsem_down_write_failed+0x13/0x20
[ 1081.899251]  [<ffffffff81269723>] ? call_rwsem_down_write_failed+0x13/0x20
[ 1081.901063]  [<ffffffff81089fae>] ? __down_write_nested.isra.0+0x1f/0x21
[ 1081.902365]  [<ffffffff814855bd>] down_write+0x43/0x57
[ 1081.903846]  [<ffffffffa05211b0>] ? btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs]
[ 1081.906078]  [<ffffffffa05211b0>] btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs]
[ 1081.908846]  [<ffffffff8108d461>] ? mark_held_locks+0x56/0x6c
[ 1081.910409]  [<ffffffffa0521282>] btrfs_check_data_free_space+0x40/0x59 [btrfs]
[ 1081.912482]  [<ffffffffa05228f5>] btrfs_delalloc_reserve_space+0x1e/0x4e [btrfs]
[ 1081.914597]  [<ffffffffa053620a>] btrfs_direct_IO+0x10c/0x27e [btrfs]
[ 1081.919037]  [<ffffffff8111d9a1>] generic_file_direct_write+0xb3/0x128
[ 1081.920754]  [<ffffffffa05463c3>] btrfs_file_write_iter+0x229/0x408 [btrfs]
[ 1081.922496]  [<ffffffff8108ae38>] ? __lock_is_held+0x38/0x50
[ 1081.923922]  [<ffffffff8117279e>] __vfs_write+0x7c/0xa5
[ 1081.925275]  [<ffffffff81172cda>] vfs_write+0xa0/0xe4
[ 1081.926584]  [<ffffffff811734cc>] SyS_write+0x50/0x7e
[ 1081.927968]  [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f
[ 1081.985293] INFO: lockdep is turned off.
[ 1081.986132] INFO: task fio:8249 blocked for more than 120 seconds.
[ 1081.987434]       Not tainted 4.4.0-rc6-btrfs-next-18+ #1
[ 1081.988534] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1081.990147] fio        D ffff880218febbb8     0  8249   8240 0x00000000
[ 1081.991626]  ffff880218febbb8 00ffffff81486b8e ffff88020000000b ffff88023ed75240
[ 1081.993258]  ffff8802120a9a00 ffff880218fec000 ffff88020a4d5318 ffff8802120a9a00
[ 1081.994850]  ffffffff00000001 ffff8802120a9a00 ffff880218febbd0 ffffffff81482ba4
[ 1081.996485] Call Trace:
[ 1081.997037]  [<ffffffff81482ba4>] schedule+0x7f/0x97
[ 1081.998017]  [<ffffffff81485eb5>] rwsem_down_write_failed+0x2d5/0x325
[ 1081.999241]  [<ffffffff810852a5>] ? finish_wait+0x6d/0x76
[ 1082.000306]  [<ffffffff81269723>] call_rwsem_down_write_failed+0x13/0x20
[ 1082.001533]  [<ffffffff81269723>] ? call_rwsem_down_write_failed+0x13/0x20
[ 1082.002776]  [<ffffffff81089fae>] ? __down_write_nested.isra.0+0x1f/0x21
[ 1082.003995]  [<ffffffff814855bd>] down_write+0x43/0x57
[ 1082.005000]  [<ffffffffa05211b0>] ? btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs]
[ 1082.007403]  [<ffffffffa05211b0>] btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs]
[ 1082.008988]  [<ffffffffa0545064>] btrfs_fallocate+0x7c1/0xc2f [btrfs]
[ 1082.010193]  [<ffffffff8108a1ba>] ? percpu_down_read+0x4e/0x77
[ 1082.011280]  [<ffffffff81174c4c>] ? __sb_start_write+0x5f/0xb0
[ 1082.012265]  [<ffffffff81174c4c>] ? __sb_start_write+0x5f/0xb0
[ 1082.013021]  [<ffffffff811712e4>] vfs_fallocate+0x170/0x1ff
[ 1082.013738]  [<ffffffff81181ebb>] ioctl_preallocate+0x89/0x9b
[ 1082.014778]  [<ffffffff811822d7>] do_vfs_ioctl+0x40a/0x4ea
[ 1082.015778]  [<ffffffff81176ea7>] ? SYSC_newfstat+0x25/0x2e
[ 1082.016806]  [<ffffffff8118b4de>] ? __fget_light+0x4d/0x71
[ 1082.017789]  [<ffffffff8118240e>] SyS_ioctl+0x57/0x79
[ 1082.018706]  [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f

This happens because we can recursively acquire the semaphore
fs_info->delayed_iput_sem when attempting to allocate space to satisfy
a file write request as shown in the first trace above - when committing
a transaction we acquire (down_read) the semaphore before running the
delayed iputs, and when running a delayed iput() we can end up calling
an inode's eviction handler, which in turn commits another transaction
and attempts to acquire (down_read) again the semaphore to run more
delayed iput operations.
This results in a deadlock because if a task acquires multiple times a
semaphore it should invoke down_read_nested() with a different lockdep
class for each level of recursion.

Fix this by simplifying the implementation and use a mutex instead that
is acquired by the cleaner kthread before it runs the delayed iputs
instead of always acquiring a semaphore before delayed references are
run from anywhere.

Fixes: d7c151717a (btrfs: Fix NO_SPACE bug caused by delayed-iput)
Cc: stable@vger.kernel.org   # 4.1+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 16:23:21 -05:00
David Sterba
f3eaec3850 btrfs: put delayed item hook into inode
[ Upstream commit 8089fe62c6 ]

Inodes for delayed iput allocate a trivial helper structure, let's place
the list hook directly into the inode and save a kmalloc (killing a
__GFP_NOFAIL as a bonus) at the cost of increasing size of btrfs_inode.

The inode can be put into the delayed_iputs list more than once and we
have to keep the count. This means we can't use the list_splice to
process a bunch of inodes because we'd lost track of the count if the
inode is put into the delayed iputs again while it's processed.

Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 16:23:21 -05:00
Dave Chinner
4126014e7c xfs: log mount failures don't wait for buffers to be released
[ Upstream commit 85bec5460a ]

Recently I've been seeing xfs/051 fail on 1k block size filesystems.
Trying to trace the events during the test lead to the problem going
away, indicating that it was a race condition that lead to this
ASSERT failure:

XFS: Assertion failed: atomic_read(&pag->pag_ref) == 0, file: fs/xfs/xfs_mount.c, line: 156
.....
[<ffffffff814e1257>] xfs_free_perag+0x87/0xb0
[<ffffffff814e21b9>] xfs_mountfs+0x4d9/0x900
[<ffffffff814e5dff>] xfs_fs_fill_super+0x3bf/0x4d0
[<ffffffff811d8800>] mount_bdev+0x180/0x1b0
[<ffffffff814e3ff5>] xfs_fs_mount+0x15/0x20
[<ffffffff811d90a8>] mount_fs+0x38/0x170
[<ffffffff811f4347>] vfs_kern_mount+0x67/0x120
[<ffffffff811f7018>] do_mount+0x218/0xd60
[<ffffffff811f7e5b>] SyS_mount+0x8b/0xd0

When I finally caught it with tracing enabled, I saw that AG 2 had
an elevated reference count and a buffer was responsible for it. I
tracked down the specific buffer, and found that it was missing the
final reference count release that would put it back on the LRU and
hence be found by xfs_wait_buftarg() calls in the log mount failure
handling.

The last four traces for the buffer before the assert were (trimmed
for relevance)

kworker/0:1-5259   xfs_buf_iodone:        hold 2  lock 0 flags ASYNC
kworker/0:1-5259   xfs_buf_ioerror:       hold 2  lock 0 error -5
mount-7163	   xfs_buf_lock_done:     hold 2  lock 0 flags ASYNC
mount-7163	   xfs_buf_unlock:        hold 2  lock 1 flags ASYNC

This is an async write that is completing, so there's nobody waiting
for it directly.  Hence we call xfs_buf_relse() once all the
processing is complete. That does:

static inline void xfs_buf_relse(xfs_buf_t *bp)
{
	xfs_buf_unlock(bp);
	xfs_buf_rele(bp);
}

Now, it's clear that mount is waiting on the buffer lock, and that
it has been released by xfs_buf_relse() and gained by mount. This is
expected, because at this point the mount process is in
xfs_buf_delwri_submit() waiting for all the IO it submitted to
complete.

The mount process, however, is waiting on the lock for the buffer
because it is in xfs_buf_delwri_submit(). This waits for IO
completion, but it doesn't wait for the buffer reference owned by
the IO to go away. The mount process collects all the completions,
fails the log recovery, and the higher level code then calls
xfs_wait_buftarg() to free all the remaining buffers in the
filesystem.

The issue is that on unlocking the buffer, the scheduler has decided
that the mount process has higher priority than the the kworker
thread that is running the IO completion, and so immediately
switched contexts to the mount process from the semaphore unlock
code, hence preventing the kworker thread from finishing the IO
completion and releasing the IO reference to the buffer.

Hence by the time that xfs_wait_buftarg() is run, the buffer still
has an active reference and so isn't on the LRU list that the
function walks to free the remaining buffers. Hence we miss that
buffer and continue onwards to tear down the mount structures,
at which time we get find a stray reference count on the perag
structure. On a non-debug kernel, this will be ignored and the
structure torn down and freed. Hence when the kworker thread is then
rescheduled and the buffer released and freed, it will access a
freed perag structure.

The problem here is that when the log mount fails, we still need to
quiesce the log to ensure that the IO workqueues have returned to
idle before we run xfs_wait_buftarg(). By synchronising the
workqueues, we ensure that all IO completions are fully processed,
not just to the point where buffers have been unlocked. This ensures
we don't end up in the situation above.

cc: <stable@vger.kernel.org> # 3.18
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 16:23:20 -05:00
xuejiufei
8467278d96 ocfs2/dlm: ignore cleaning the migration mle that is inuse
[ Upstream commit bef5502de0 ]

We have found that migration source will trigger a BUG that the refcount
of mle is already zero before put when the target is down during
migration.  The situation is as follows:

dlm_migrate_lockres
  dlm_add_migration_mle
  dlm_mark_lockres_migrating
  dlm_get_mle_inuse
  <<<<<< Now the refcount of the mle is 2.
  dlm_send_one_lockres and wait for the target to become the
  new master.
  <<<<<< o2hb detect the target down and clean the migration
  mle. Now the refcount is 1.

dlm_migrate_lockres woken, and put the mle twice when found the target
goes down which trigger the BUG with the following message:

  "ERROR: bad mle: ".

Signed-off-by: Jiufei Xue <xuejiufei@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 16:23:16 -05:00
Vasily Averin
c5882812d2 cifs_dbg() outputs an uninitialized buffer in cifs_readdir()
[ Upstream commit 01b9b0b286 ]

In some cases tmp_bug can be not filled in cifs_filldir and stay uninitialized,
therefore its printk with "%s" modifier can leak content of kernelspace memory.
If old content of this buffer does not contain '\0' access bejond end of
allocated object can crash the host.

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Steve French <sfrench@localhost.localdomain>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 16:23:16 -05:00
Rabin Vincent
99b79b15df cifs: fix race between call_async() and reconnect()
[ Upstream commit 820962dc70 ]

cifs_call_async() queues the MID to the pending list and calls
smb_send_rqst().  If smb_send_rqst() performs a partial send, it sets
the tcpStatus to CifsNeedReconnect and returns an error code to
cifs_call_async().  In this case, cifs_call_async() removes the MID
from the list and returns to the caller.

However, cifs_call_async() releases the server mutex _before_ removing
the MID.  This means that a cifs_reconnect() can race with this function
and manage to remove the MID from the list and delete the entry before
cifs_call_async() calls cifs_delete_mid().  This leads to various
crashes due to the use after free in cifs_delete_mid().

Task1				Task2

cifs_call_async():
 - rc = -EAGAIN
 - mutex_unlock(srv_mutex)

				cifs_reconnect():
				 - mutex_lock(srv_mutex)
				 - mutex_unlock(srv_mutex)
				 - list_delete(mid)
				 - mid->callback()
				 	cifs_writev_callback():
				 		- mutex_lock(srv_mutex)
						- delete(mid)
				 		- mutex_unlock(srv_mutex)

 - cifs_delete_mid(mid) <---- use after free

Fix this by removing the MID in cifs_call_async() before releasing the
srv_mutex.  Also hold the srv_mutex in cifs_reconnect() until the MIDs
are moved out of the pending list.

Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <sfrench@localhost.localdomain>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 16:23:15 -05:00
Jamie Bainbridge
ca7342a8a3 cifs: Ratelimit kernel log messages
[ Upstream commit ec7147a99e ]

Under some conditions, CIFS can repeatedly call the cifs_dbg() logging
wrapper. If done rapidly enough, the console framebuffer can softlockup
or "rcu_sched self-detected stall". Apply the built-in log ratelimiters
to prevent such hangs.

Signed-off-by: Jamie Bainbridge <jamie.bainbridge@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 16:23:15 -05:00
Dave Chinner
e52b0623ee xfs: handle dquot buffer readahead in log recovery correctly
[ Upstream commit 7d6a13f023 ]

When we do dquot readahead in log recovery, we do not use a verifier
as the underlying buffer may not have dquots in it. e.g. the
allocation operation hasn't yet been replayed. Hence we do not want
to fail recovery because we detect an operation to be replayed has
not been run yet. This problem was addressed for inodes in commit
d891400 ("xfs: inode buffers may not be valid during recovery
readahead") but the problem was not recognised to exist for dquots
and their buffers as the dquot readahead did not have a verifier.

The result of not using a verifier is that when the buffer is then
next read to replay a dquot modification, the dquot buffer verifier
will only be attached to the buffer if *readahead is not complete*.
Hence we can read the buffer, replay the dquot changes and then add
it to the delwri submission list without it having a verifier
attached to it. This then generates warnings in xfs_buf_ioapply(),
which catches and warns about this case.

Fix this and make it handle the same readahead verifier error cases
as for inode buffers by adding a new readahead verifier that has a
write operation as well as a read operation that marks the buffer as
not done if any corruption is detected.  Also make sure we don't run
readahead if the dquot buffer has been marked as cancelled by
recovery.

This will result in readahead either succeeding and the buffer
having a valid write verifier, or readahead failing and the buffer
state requiring the subsequent read to resubmit the IO with the new
verifier.  In either case, this will result in the buffer always
ending up with a valid write verifier on it.

Note: we also need to fix the inode buffer readahead error handling
to mark the buffer with EIO. Brian noticed the code I copied from
there wrong during review, so fix it at the same time. Add comments
linking the two functions that handle readahead verifier errors
together so we don't forget this behavioural link in future.

cc: <stable@vger.kernel.org> # 3.12 - current
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 14:01:46 -05:00
Dave Chinner
848235ac48 xfs: inode recovery readahead can race with inode buffer creation
[ Upstream commit b79f4a1c68 ]

When we do inode readahead in log recovery, we do can do the
readahead before we've replayed the icreate transaction that stamps
the buffer with inode cores. The inode readahead verifier catches
this and marks the buffer as !done to indicate that it doesn't yet
contain valid inodes.

In adding buffer error notification  (i.e. setting b_error = -EIO at
the same time as as we clear the done flag) to such a readahead
verifier failure, we can then get subsequent inode recovery failing
with this error:

XFS (dm-0): metadata I/O error: block 0xa00060 ("xlog_recover_do..(read#2)") error 5 numblks 32

This occurs when readahead completion races with icreate item replay
such as:

	inode readahead
		find buffer
		lock buffer
		submit RA io
	....
	icreate recovery
	    xfs_trans_get_buffer
		find buffer
		lock buffer
		<blocks on RA completion>
	.....
	<ra completion>
		fails verifier
		clear XBF_DONE
		set bp->b_error = -EIO
		release and unlock buffer
	<icreate gains lock>
	icreate initialises buffer
	marks buffer as done
	adds buffer to delayed write queue
	releases buffer

At this point, we have an initialised inode buffer that is up to
date but has an -EIO state registered against it. When we finally
get to recovering an inode in that buffer:

	inode item recovery
	    xfs_trans_read_buffer
		find buffer
		lock buffer
		sees XBF_DONE is set, returns buffer
	    sees bp->b_error is set
		fail log recovery!

Essentially, we need xfs_trans_get_buf_map() to clear the error status of
the buffer when doing a lookup. This function returns uninitialised
buffers, so the buffer returned can not be in an error state and
none of the code that uses this function expects b_error to be set
on return. Indeed, there is an ASSERT(!bp->b_error); in the
transaction case in xfs_trans_get_buf_map() that would have caught
this if log recovery used transactions....

This patch firstly changes the inode readahead failure to set -EIO
on the buffer, and secondly changes xfs_buf_get_map() to never
return a buffer with an error state set so this first change doesn't
cause unexpected log recovery failures.

cc: <stable@vger.kernel.org> # 3.12 - current
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 14:01:46 -05:00
Vegard Nossum
4e623240d3 uml: fix hostfs mknod()
[ Upstream commit 9f2dfda2f2 ]

An inverted return value check in hostfs_mknod() caused the function
to return success after handling it as an error (and cleaning up).

It resulted in the following segfault when trying to bind() a named
unix socket:

  Pid: 198, comm: a.out Not tainted 4.4.0-rc4
  RIP: 0033:[<0000000061077df6>]
  RSP: 00000000daae5d60  EFLAGS: 00010202
  RAX: 0000000000000000 RBX: 000000006092a460 RCX: 00000000dfc54208
  RDX: 0000000061073ef1 RSI: 0000000000000070 RDI: 00000000e027d600
  RBP: 00000000daae5de0 R08: 00000000da980ac0 R09: 0000000000000000
  R10: 0000000000000003 R11: 00007fb1ae08f72a R12: 0000000000000000
  R13: 000000006092a460 R14: 00000000daaa97c0 R15: 00000000daaa9a88
  Kernel panic - not syncing: Kernel mode fault at addr 0x40, ip 0x61077df6
  CPU: 0 PID: 198 Comm: a.out Not tainted 4.4.0-rc4 #1
  Stack:
   e027d620 dfc54208 0000006f da981398
   61bee000 0000c1ed daae5de0 0000006e
   e027d620 dfcd4208 00000005 6092a460
  Call Trace:
   [<60dedc67>] SyS_bind+0xf7/0x110
   [<600587be>] handle_syscall+0x7e/0x80
   [<60066ad7>] userspace+0x3e7/0x4e0
   [<6006321f>] ? save_registers+0x1f/0x40
   [<6006c88e>] ? arch_prctl+0x1be/0x1f0
   [<60054985>] fork_handler+0x85/0x90

Let's also get rid of the "cosmic ray protection" while we're at it.

Fixes: e9193059b1 "hostfs: fix races in dentry_name() and inode_name()"
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 14:01:45 -05:00
Jeff Layton
2e21928b85 locks: fix unlock when fcntl_setlk races with a close
[ Upstream commit 7f3697e24d ]

Dmitry reported that he was able to reproduce the WARN_ON_ONCE that
fires in locks_free_lock_context when the flc_posix list isn't empty.

The problem turns out to be that we're basically rebuilding the
file_lock from scratch in fcntl_setlk when we discover that the setlk
has raced with a close. If the l_whence field is SEEK_CUR or SEEK_END,
then we may end up with fl_start and fl_end values that differ from
when the lock was initially set, if the file position or length of the
file has changed in the interim.

Fix this by just reusing the same lock request structure, and simply
override fl_type value with F_UNLCK as appropriate. That ensures that
we really are unlocking the lock that was initially set.

While we're there, make sure that we do pop a WARN_ON_ONCE if the
removal ever fails. Also return -EBADF in this event, since that's
what we would have returned if the close had happened earlier.

Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Fixes: c293621bbf (stale POSIX lock handling)
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Acked-by: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 14:01:44 -05:00
David Sterba
1ecdadef5d btrfs: handle invalid num_stripes in sys_array
[ Upstream commit f5cdedd73f ]

We can handle the special case of num_stripes == 0 directly inside
btrfs_read_sys_array. The BUG_ON in btrfs_chunk_item_size is there to
catch other unhandled cases where we fail to validate external data.

A crafted or corrupted image crashes at mount time:

BTRFS: device fsid 9006933e-2a9a-44f0-917f-514252aeec2c devid 1 transid 7 /dev/loop0
BTRFS info (device loop0): disk space caching is enabled
BUG: failure at fs/btrfs/ctree.h:337/btrfs_chunk_item_size()!
Kernel panic - not syncing: BUG!
CPU: 0 PID: 313 Comm: mount Not tainted 4.2.5-00657-ge047887-dirty #25
Stack:
 637af890 60062489 602aeb2e 604192ba
 60387961 00000011 637af8a0 6038a835
 637af9c0 6038776b 634ef32b 00000000
Call Trace:
 [<6001c86d>] show_stack+0xfe/0x15b
 [<6038a835>] dump_stack+0x2a/0x2c
 [<6038776b>] panic+0x13e/0x2b3
 [<6020f099>] btrfs_read_sys_array+0x25d/0x2ff
 [<601cfbbe>] open_ctree+0x192d/0x27af
 [<6019c2c1>] btrfs_mount+0x8f5/0xb9a
 [<600bc9a7>] mount_fs+0x11/0xf3
 [<600d5167>] vfs_kern_mount+0x75/0x11a
 [<6019bcb0>] btrfs_mount+0x2e4/0xb9a
 [<600bc9a7>] mount_fs+0x11/0xf3
 [<600d5167>] vfs_kern_mount+0x75/0x11a
 [<600d710b>] do_mount+0xa35/0xbc9
 [<600d7557>] SyS_mount+0x95/0xc8
 [<6001e884>] handle_syscall+0x6b/0x8e

Reported-by: Jiri Slaby <jslaby@suse.com>
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
CC: stable@vger.kernel.org	# 3.19+
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-03 14:01:44 -05:00
Andrew Gabbasov
516a102b0a udf: Check output buffer length when converting name to CS0
[ Upstream commit bb00c898ad ]

If a name contains at least some characters with Unicode values
exceeding single byte, the CS0 output should have 2 bytes per character.
And if other input characters have single byte Unicode values, then
the single input byte is converted to 2 output bytes, and the length
of output becomes larger than the length of input. And if the input
name is long enough, the output length may exceed the allocated buffer
length.

All this means that conversion from UTF8 or NLS to CS0 requires
checking of output length in order to stop when it exceeds the given
output buffer size.

[JK: Make code return -ENAMETOOLONG instead of silently truncating the
name]

CC: stable@vger.kernel.org
Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 14:54:15 -05:00
Andrew Gabbasov
d6341753c4 udf: Prevent buffer overrun with multi-byte characters
[ Upstream commit ad402b265e ]

udf_CS0toUTF8 function stops the conversion when the output buffer
length reaches UDF_NAME_LEN-2, which is correct maximum name length,
but, when checking, it leaves the space for a single byte only,
while multi-bytes output characters can take more space, causing
buffer overflow.

Similar error exists in udf_CS0toNLS function, that restricts
the output length to UDF_NAME_LEN, while actual maximum allowed
length is UDF_NAME_LEN-2.

In these cases the output can override not only the current buffer
length field, causing corruption of the name buffer itself, but also
following allocation structures, causing kernel crash.

Adjust the output length checks in both functions to prevent buffer
overruns in case of multi-bytes UTF8 or NLS characters.

CC: stable@vger.kernel.org
Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 14:54:12 -05:00
Trond Myklebust
8572f2fa31 NFS: Fix attribute cache revalidation
[ Upstream commit ade14a7df7 ]

If a NFSv4 client uses the cache_consistency_bitmask in order to
request only information about the change attribute, timestamps and
size, then it has not revalidated all attributes, and hence the
attribute timeout timestamp should not be updated.

Reported-by: Donald Buczek <buczek@molgen.mpg.de>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 14:53:22 -05:00
Trond Myklebust
226864aff7 NFS: Remove the "NFS_CAP_CHANGE_ATTR" capability
[ Upstream commit cd81259979 ]

Setting the change attribute has been mandatory for all NFS versions, since
commit 3a1556e866 ("NFSv2/v3: Simulate the change attribute"). We should
therefore not have anything be conditional on it being set/unset.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 14:53:19 -05:00
Andrew Elble
40b7566cb9 nfs: Fix race in __update_open_stateid()
[ Upstream commit 361cad3c89 ]

We've seen this in a packet capture - I've intermixed what I
think was going on. The fix here is to grab the so_lock sooner.

1964379 -> #1 open (for write) reply seqid=1
1964393 -> #2 open (for read) reply seqid=2

  __nfs4_close(), state->n_wronly--
  nfs4_state_set_mode_locked(), changes state->state = [R]
  state->flags is [RW]
  state->state is [R], state->n_wronly == 0, state->n_rdonly == 1

1964398 -> #3 open (for write) call -> because close is already running
1964399 -> downgrade (to read) call seqid=2 (close of #1)
1964402 -> #3 open (for write) reply seqid=3

 __update_open_stateid()
   nfs_set_open_stateid_locked(), changes state->flags
   state->flags is [RW]
   state->state is [R], state->n_wronly == 0, state->n_rdonly == 1
   new sequence number is exposed now via nfs4_stateid_copy()

   next step would be update_open_stateflags(), pending so_lock

1964403 -> downgrade reply seqid=2, fails with OLD_STATEID (close of #1)

   nfs4_close_prepare() gets so_lock and recalcs flags -> send close

1964405 -> downgrade (to read) call seqid=3 (close of #1 retry)

   __update_open_stateid() gets so_lock
 * update_open_stateflags() updates state->n_wronly.
   nfs4_state_set_mode_locked() updates state->state

   state->flags is [RW]
   state->state is [RW], state->n_wronly == 1, state->n_rdonly == 1

 * should have suppressed the preceding nfs4_close_prepare() from
   sending open_downgrade

1964406 -> write call
1964408 -> downgrade (to read) reply seqid=4 (close of #1 retry)

   nfs_clear_open_stateid_locked()
   state->flags is [R]
   state->state is [RW], state->n_wronly == 1, state->n_rdonly == 1

1964409 -> write reply (fails, openmode)

Signed-off-by: Andrew Elble <aweits@rit.edu>
Cc: stable@vger,kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 12:39:50 -05:00
Vegard Nossum
4476dc6770 udf: limit the maximum number of indirect extents in a row
[ Upstream commit b0918d9f47 ]

udf_next_aext() just follows extent pointers while extents are marked as
indirect. This can loop forever for corrupted filesystem. Limit number
the of indirect extents we are willing to follow in a row.

[JK: Updated changelog, limit, style]

Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Cc: stable@vger.kernel.org
Cc: Jan Kara <jack@suse.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 12:39:42 -05:00
Konstantin Khlebnikov
1cbc3b7717 ovl: check dentry positiveness in ovl_cleanup_whiteouts()
[ Upstream commit 84889d4933 ]

This patch fixes kernel crash at removing directory which contains
whiteouts from lower layers.

Cache of directory content passed as "list" contains entries from all
layers, including whiteouts from lower layers. So, lookup in upper dir
(moved into work at this stage) will return negative entry. Plus this
cache is filled long before and we can race with external removal.

Example:
 mkdir -p lower0/dir lower1/dir upper work overlay
 touch lower0/dir/a lower0/dir/b
 mknod lower1/dir/a c 0 0
 mount -t overlay none overlay -o lowerdir=lower1:lower0,upperdir=upper,workdir=work
 rm -fr overlay/dir

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org> # 3.18+
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 11:37:35 -05:00
Miklos Szeredi
c8e1bebf86 ovl: setattr: check permissions before copy-up
[ Upstream commit cf9a6784f7 ]

Without this copy-up of a file can be forced, even without actually being
allowed to do anything on the file.

[Arnd Bergmann] include <linux/pagemap.h> for PAGE_CACHE_SIZE (used by
MAX_LFS_FILESIZE definition).

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 11:37:32 -05:00
Miklos Szeredi
ba122961c9 ovl: root: copy attr
[ Upstream commit ed06e06977 ]

We copy i_uid and i_gid of underlying inode into overlayfs inode.  Except
for the root inode.

Fix this omission.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 11:37:12 -05:00
Vito Caputo
3c0a63d74b ovl: use a minimal buffer in ovl_copy_xattr
[ Upstream commit e4ad29fa0d ]

Rather than always allocating the high-order XATTR_SIZE_MAX buffer
which is costly and prone to failure, only allocate what is needed and
realloc if necessary.

Fixes https://github.com/coreos/bugs/issues/489

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 10:39:24 -05:00
Miklos Szeredi
c000201d0b ovl: allow zero size xattr
[ Upstream commit 97daf8b97a ]

When ovl_copy_xattr() encountered a zero size xattr no more xattrs were
copied and the function returned success.  This is clearly not the desired
behavior.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-02-01 10:39:21 -05:00
Al Viro
57b7d61c2d fix the regression from "direct-io: Fix negative return from dio read beyond eof"
commit 2d4594acbf upstream.

Sure, it's better to bail out of past-the-eof read and return 0 than return
a bogus negative value on such.  Only we'd better make sure we are bailing out
with 0 and not -ENOMEM...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31 11:23:40 -08:00
Jan Kara
8885e7f3d7 direct-io: Fix negative return from dio read beyond eof
commit 74cedf9b6c upstream.

Assume a filesystem with 4KB blocks. When a file has size 1000 bytes and
we issue direct IO read at offset 1024, blockdev_direct_IO() reads the
tail of the last block and the logic for handling short DIO reads in
dio_complete() results in a return value -24 (1000 - 1024) which
obviously confuses userspace.

Fix the problem by bailing out early once we sample i_size and can
reliably check that direct IO read starts beyond i_size.

Reported-by: Avi Kivity <avi@scylladb.com>
Fixes: 9fe55eea7e
CC: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31 11:23:40 -08:00
Arnd Bergmann
3b16e64154 ceph: fix message length computation
commit 777d738a5e upstream.

create_request_message() computes the maximum length of a message,
but uses the wrong type for the time stamp: sizeof(struct timespec)
may be 8 or 16 depending on the architecture, while sizeof(struct
ceph_timespec) is always 8, and that is what gets put into the
message.

Found while auditing the uses of timespec for y2038 problems.

Fixes: b8e69066d8 ("ceph: include time stamp in every MDS request")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 21:24:37 -08:00
Junxiao Bi
273ef13347 ocfs2: fix umask ignored issue
commit 8f1eb48758 upstream.

New created file's mode is not masked with umask, and this makes umask not
work for ocfs2 volume.

Fixes: 702e5bc ("ocfs2: use generic posix ACL infrastructure")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Gang He <ghe@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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 21:24:37 -08:00
Jeff Layton
2cc11ce906 nfs: if we have no valid attrs, then don't declare the attribute cache valid
commit c812012f9c upstream.

If we pass in an empty nfs_fattr struct to nfs_update_inode, it will
(correctly) not update any of the attributes, but it then clears the
NFS_INO_INVALID_ATTR flag, which indicates that the attributes are
up to date. Don't clear the flag if the fattr struct has no valid
attrs to apply.

Reviewed-by: Steve French <steve.french@primarydata.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 21:24:37 -08:00