Re: [syzbot] [gfs2?] KASAN: slab-use-after-free Write in gfs2_qd_dealloc (2)

[Edward Adam Davis]

please test uaf in gfs2_qd_dealloc

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 18737353cca0

diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 572d58e86296..91103e0307ac 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -1321,6 +1321,8 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc)
 fail_delete_wq:
 	destroy_workqueue(sdp->sd_delete_wq);
 fail_free:
+	wait_event(sdp->sd_kill_wait,
+                atomic_read(&sdp->sd_quota_count) == 0);
 	free_sbd(sdp);
 	sb->s_fs_info = NULL;
 	return error;