fs/hfsplus/extents.c: fix concurrent acess of alloc_blocks
authorSougata Santra <sougata@tuxera.com>
Thu, 3 Apr 2014 21:50:34 +0000 (14:50 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 3 Apr 2014 23:21:26 +0000 (16:21 -0700)
commitd7bdb996aef67ea24c62707ca4e29b07025e9683
tree619189c603f5ff8dca0f83880bc38382da61039d
parentabfeb724b43f371ea70ec2c1290ed33e6f65db60
fs/hfsplus/extents.c: fix concurrent acess of alloc_blocks

Concurrent access to alloc_blocks in hfsplus_inode_info() is protected
by extents_lock mutex.  This patch fixes two instances where
alloc_blocks modification was not protected with this lock.

This fixes possible allocation bitmap corruption in race conditions
while extending and truncating files.

[akpm@linux-foundation.org: take extents_lock before taking a copy of ->alloc_blocks]
[akpm@linux-foundation.org: remove now-unused label `out']
Signed-off-by: Sougata Santra <sougata@tuxera.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/hfsplus/extents.c