From bdcb8aa434c6d36b5c215d02a9ef07551be25a37 Mon Sep 17 00:00:00 2001 From: Juntong Deng Date: Mon, 30 Oct 2023 05:10:06 +0800 Subject: gfs2: Fix slab-use-after-free in gfs2_qd_dealloc In gfs2_put_super(), whether withdrawn or not, the quota should be cleaned up by gfs2_quota_cleanup().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 Signed-off-by: Andreas Gruenbacher --- fs/gfs2/super.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'fs/gfs2') diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index 726f062bc490..84e88b50ed92 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -602,13 +602,15 @@ restart: } 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 */ -- cgit