From: Frederic Weisbecker Date: Wed, 24 Nov 2010 20:57:15 +0000 (-0800) Subject: reiserfs: fix inode mutex - reiserfs lock misordering X-Git-Tag: firefly_0821_release~9833^2~79^2^2~198 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=fec32bc5795b53a354d991c9652b671359e9f494;p=firefly-linux-kernel-4.4.55.git reiserfs: fix inode mutex - reiserfs lock misordering commit da905873effecd1c0166e578bc4b5006f041b18b upstream. reiserfs_unpack() locks the inode mutex with reiserfs_mutex_lock_safe() to protect against reiserfs lock dependency. However this protection requires to have the reiserfs lock to be locked. This is the case if reiserfs_unpack() is called by reiserfs_ioctl but not from reiserfs_quota_on() when it tries to unpack tails of quota files. Fix the ordering of the two locks in reiserfs_unpack() to fix this issue. Signed-off-by: Frederic Weisbecker Reported-by: Markus Gapp Reported-by: Jan Kara Cc: Jeff Mahoney Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/reiserfs/ioctl.c b/fs/reiserfs/ioctl.c index 5cbb81e134ac..4131f4a49391 100644 --- a/fs/reiserfs/ioctl.c +++ b/fs/reiserfs/ioctl.c @@ -186,12 +186,11 @@ int reiserfs_unpack(struct inode *inode, struct file *filp) return 0; } - /* we need to make sure nobody is changing the file size beneath - ** us - */ - reiserfs_mutex_lock_safe(&inode->i_mutex, inode->i_sb); depth = reiserfs_write_lock_once(inode->i_sb); + /* we need to make sure nobody is changing the file size beneath us */ + reiserfs_mutex_lock_safe(&inode->i_mutex, inode->i_sb); + write_from = inode->i_size & (blocksize - 1); /* if we are on a block boundary, we are already unpacked. */ if (write_from == 0) {