linux/fs
Jan Kara ed8ad83808 ext4: fix bh->b_state corruption
ext4 can update bh->b_state non-atomically in _ext4_get_block() and
ext4_da_get_block_prep(). Usually this is fine since bh is just a
temporary storage for mapping information on stack but in some cases it
can be fully living bh attached to a page. In such case non-atomic
update of bh->b_state can race with an atomic update which then gets
lost. Usually when we are mapping bh and thus updating bh->b_state
non-atomically, nobody else touches the bh and so things work out fine
but there is one case to especially worry about: ext4_finish_bio() uses
BH_Uptodate_Lock on the first bh in the page to synchronize handling of
PageWriteback state. So when blocksize < pagesize, we can be atomically
modifying bh->b_state of a buffer that actually isn't under IO and thus
can race e.g. with delalloc trying to map that buffer. The result is
that we can mistakenly set / clear BH_Uptodate_Lock bit resulting in the
corruption of PageWriteback state or missed unlock of BH_Uptodate_Lock.

Fix the problem by always updating bh->b_state bits atomically.

CC: stable@vger.kernel.org
Reported-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-02-19 00:18:25 -05:00
..
9p wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
adfs fs/adfs/adfs.h: tidy up comments 2016-01-20 17:09:18 -08:00
affs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
afs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
autofs4 switch ->get_link() to delayed_call, kill ->put_link() 2015-12-30 13:01:03 -05:00
befs kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
bfs kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
btrfs Merge branch 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2016-01-29 15:46:49 -08:00
cachefiles wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2016-01-24 12:34:13 -08:00
cifs Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6 2016-01-24 12:31:12 -08:00
coda Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
configfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
cramfs don't put symlink bodies in pagecache into highmem 2015-12-08 22:41:36 -05:00
debugfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
devpts wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
dlm [regression] fix braino in fs/dlm/user.c 2016-01-21 17:45:15 -05:00
ecryptfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
efivarfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
efs kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
exofs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
exportfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
ext2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
ext4 ext4: fix bh->b_state corruption 2016-02-19 00:18:25 -05:00
f2fs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
fat wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
freevxfs don't put symlink bodies in pagecache into highmem 2015-12-08 22:41:36 -05:00
fscache FS-Cache: Handle a write to the page immediately beyond the EOF marker 2015-11-11 02:11:02 -05:00
fuse wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
gfs2 wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
hfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
hfsplus wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
hostfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
hpfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
hugetlbfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
isofs kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
jbd2 fs: use block_device name vsprintf helper 2016-01-06 13:03:18 -05:00
jffs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
jfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
kernfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
lockd lockd: constify nlmsvc_binding structure 2016-01-07 10:10:50 -05:00
logfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
minix kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
ncpfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
nfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
nfs_common
nfsd wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
nilfs2 wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
nls
notify fsnotify: destroy marks with call_srcu instead of dedicated thread 2016-01-14 16:00:49 -08:00
ntfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
ocfs2 wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
omfs
openpromfs kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
overlayfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
proc wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
pstore wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
qnx4 kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
qnx6 kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
quota wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
ramfs don't put symlink bodies in pagecache into highmem 2015-12-08 22:41:36 -05:00
reiserfs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
romfs kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
squashfs kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
sysfs platform/chrome: Branch for v4.4 2015-11-13 21:53:18 -08:00
sysv kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
tracefs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
ubifs wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
udf Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
ufs kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
xfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
aio.c
anon_inodes.c
attr.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
bad_inode.c fs/bad_inode.c: is_bad_inode can be boolean 2015-12-06 21:17:14 -05:00
binfmt_aout.c
binfmt_elf_fdpic.c libnvdimm for 4.4: 2015-11-10 12:07:22 -08:00
binfmt_elf.c ELF: Also pass any interpreter's file header to `arch_check_elf' 2016-01-20 00:39:20 +01:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
binfmt_script.c
block_dev.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
buffer.c fs: use block_device name vsprintf helper 2016-01-06 13:03:18 -05:00
char_dev.c
compat_binfmt_elf.c
compat_ioctl.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-12 17:11:47 -08:00
compat.c saner calling conventions for copy_mount_options() 2016-01-04 10:28:32 -05:00
coredump.c fs/coredump: prevent "" / "." / ".." core path components 2016-01-20 17:09:18 -08:00
dax.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
dcache.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
dcookies.c
direct-io.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
drop_caches.c
eventfd.c Documentation: filesystem: Fix typo in fs/eventfd.c 2015-12-08 14:52:03 +01:00
eventpoll.c epoll: add EPOLLEXCLUSIVE flag 2016-01-20 17:09:18 -08:00
exec.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
fcntl.c fcntl: allow to set O_DIRECT flag on pipe 2016-01-09 02:55:37 -05:00
fhandle.c
file_table.c
file.c kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
filesystems.c find_filesystem(): simplify comparison 2016-01-19 12:02:23 -05:00
fs_pin.c
fs_struct.c
fs-writeback.c cgroup, memcg, writeback: drop spurious rcu locking around mem_cgroup_css_from_page() 2016-01-15 17:56:32 -08:00
inode.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-01-23 12:24:56 -08:00
internal.h Merge branch 'for-linus' into work.misc 2016-01-08 21:20:11 -05:00
ioctl.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
Kconfig dax: re-enable dax pmd mappings 2016-01-15 17:56:32 -08:00
Kconfig.binfmt
libfs.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
locks.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
Makefile
mbcache.c
mount.h
mpage.c
namei.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
namespace.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
no-block.c
nsfs.c
open.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
pipe.c pipe: limit the per-user amount of pages allocated in pipes 2016-01-19 19:25:21 -05:00
pnode.c
pnode.h
posix_acl.c xattr handlers: Simplify list operation 2015-12-13 19:46:12 -05:00
proc_namespace.c vfs: show_vfsstat: remove redundant initialization and check of error code 2015-12-06 21:17:16 -05:00
read_write.c vfs: abort dedupe loop if fatal signals are pending 2016-01-22 20:29:55 -05:00
readdir.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
select.c poll: plug an unused argument to do_poll 2016-01-06 08:26:52 -05:00
seq_file.c fs, seqfile: always allow oom killer 2015-11-06 17:50:42 -08:00
signalfd.c
splice.c fs: __generic_file_splice_read retry lookup on AOP_TRUNCATED_PAGE 2016-01-09 02:55:35 -05:00
stack.c
stat.c fs/stat.c: drop the last new_valid_dev check 2016-01-16 11:17:23 -08:00
statfs.c
super.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2016-01-14 17:04:19 -08:00
sync.c
timerfd.c timerfd: Handle relative timers with CONFIG_TIME_LOW_RES proper 2016-01-17 11:13:55 +01:00
userfaultfd.c
utimes.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
xattr.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00