gfs2: Fix slab-use-after-free in gfs2_qd_dealloc

In gfs2_put_super(), whether withdrawn or not, the quota should
be cleaned up by gfs2_quota_cleanup().

Otherwise, struct gfs2_sbd will be freed before gfs2_qd_dealloc (rcu
callback) has run for all gfs2_quota_data objects, resulting in
use-after-free.

Also, gfs2_destroy_threads() and gfs2_quota_cleanup() is already called
by gfs2_make_fs_ro(), so in gfs2_put_super(), after calling
gfs2_make_fs_ro(), there is no need to call them again.

Reported-by: syzbot+29c47e9e51895928698c@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=29c47e9e51895928698c
Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This commit is contained in:
Juntong Deng 2023-10-30 05:10:06 +08:00 committed by Andreas Gruenbacher
parent 074d7306a4
commit bdcb8aa434

View file

@ -602,13 +602,15 @@ static void gfs2_put_super(struct super_block *sb)
}
spin_unlock(&sdp->sd_jindex_spin);
if (!sb_rdonly(sb)) {
if (!sb_rdonly(sb))
gfs2_make_fs_ro(sdp);
}
if (gfs2_withdrawn(sdp)) {
gfs2_destroy_threads(sdp);
else {
if (gfs2_withdrawn(sdp))
gfs2_destroy_threads(sdp);
gfs2_quota_cleanup(sdp);
}
WARN_ON(gfs2_withdrawing(sdp));
/* At this point, we're through modifying the disk */