tree c51fa9b5eb8a39ec51afcaf836b2a7ad597743cd
parent 443a8c41cd49de66a3fda45b32b9860ea0292b84
author Jan Kara <jack@suse.cz> 1470933535 -0400
committer Theodore Ts'o <tytso@mit.edu> 1470933535 -0400

ext4: avoid deadlock when expanding inode size

When we need to move xattrs into external xattr block, we call
ext4_xattr_block_set() from ext4_expand_extra_isize_ea(). That may end
up calling ext4_mark_inode_dirty() again which will recurse back into
the inode expansion code leading to deadlocks.

Protect from recursion using EXT4_STATE_NO_EXPAND inode flag and move
its management into ext4_expand_extra_isize_ea() since its manipulation
is safe there (due to xattr_sem) from possible races with
ext4_xattr_set_handle() which plays with it as well.

CC: stable@vger.kernel.org   # 4.4.x
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>