Commit 4013d47a authored by Jan Kara's avatar Jan Kara Committed by Theodore Ts'o
Browse files

ext4: make sure to reset inode lockdep class when quota enabling fails 



When we succeed in enabling some quota type but fail to enable another
one with quota feature, we correctly disable all enabled quota types.
However we forget to reset i_data_sem lockdep class. When the inode gets
freed and reused, it will inherit this lockdep class (i_data_sem is
initialized only when a slab is created) and thus eventually lockdep
barfs about possible deadlocks.

Reported-and-tested-by: default avatar <syzbot+3b6f9218b1301ddda3e2@syzkaller.appspotmail.com>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20211007155336.12493-3-jack@suse.cz


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 15fc69bb

fs/ext4/super.c

+12 −1
Original line number Diff line number Diff line
@@ -6837,8 +6837,19 @@ int ext4_enable_quotas(struct super_block *sb) 
					"Failed to enable quota tracking "

					"(type=%d, err=%d). Please run "

					"e2fsck to fix.", type, err);

				for (type--; type >= 0; type--)

				for (type--; type >= 0; type--) {

					struct inode *inode;



					inode = sb_dqopt(sb)->files[type];

					if (inode)

						inode = igrab(inode);

					dquot_quota_off(sb, type);

					if (inode) {

						lockdep_set_quota_inode(inode,

							I_DATA_SEM_NORMAL);

						iput(inode);

					}

				}



				return err;

			}