3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pan Bian <bianpan2016@xxxxxxx> commit 61157b24e60fb3cd1f85f2c76a7b1d628f970144 upstream. The function frees qf_inode via iput but then pass qf_inode to lockdep_set_quota_inode on the failure path. This may result in a use-after-free bug. The patch frees df_inode only when it is never used. Fixes: daf647d2dd5 ("ext4: add lockdep annotations for i_data_sem") Cc: stable@xxxxxxxxxx # 4.6 Reviewed-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Pan Bian <bianpan2016@xxxxxxx> Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ext4/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5389,9 +5389,9 @@ static int ext4_quota_enable(struct supe qf_inode->i_flags |= S_NOQUOTA; lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA); err = dquot_enable(qf_inode, type, format_id, flags); - iput(qf_inode); if (err) lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL); + iput(qf_inode); return err; }