From b9b8a41adeff5666b402996020b698504c927353 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Mon, 20 Aug 2018 11:25:33 +0300 Subject: btrfs: use after free in btrfs_quota_enable The issue here is that btrfs_commit_transaction() frees "trans" on both the error and the success path. So the problem would be if btrfs_commit_transaction() succeeds, and then qgroup_rescan_init() fails. That means that "ret" is non-zero and "trans" is non-NULL and it leads to a use after free inside the btrfs_end_transaction() macro. Fixes: 340f1aa27f36 ("btrfs: qgroups: Move transaction management inside btrfs_quota_enable/disable") Signed-off-by: Dan Carpenter Reviewed-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/qgroup.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index 4353bb69bb86..d4917c0cddf5 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -1019,10 +1019,9 @@ out_add_root: spin_unlock(&fs_info->qgroup_lock); ret = btrfs_commit_transaction(trans); - if (ret) { - trans = NULL; + trans = NULL; + if (ret) goto out_free_path; - } ret = qgroup_rescan_init(fs_info, 0, 1); if (!ret) { -- cgit v1.2.3