From: Jan Kara jack@suse.cz
stable inclusion from linux-4.19.226 commit ef41f72716c469a670b9d556b65e5ed83a3a5fd7
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commit 4013d47a5307fdb5c13370b5392498b00fedd274 upstream.
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: syzbot+3b6f9218b1301ddda3e2@syzkaller.appspotmail.com Signed-off-by: Jan Kara jack@suse.cz Cc: stable@kernel.org Link: https://lore.kernel.org/r/20211007155336.12493-3-jack@suse.cz Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yongqiang Liu liuyongqiang13@huawei.com Signed-off-by: Laibin Qiu qiulaibin@huawei.com --- fs/ext4/super.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 8f9d60ec607e..3100f4aa2d59 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -6166,8 +6166,19 @@ static 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; }