From fe5e7ba11fcf1d75af8173836309e8562aefedef Mon Sep 17 00:00:00 2001 From: Bob Peterson Date: Thu, 14 Nov 2019 09:49:11 -0500 Subject: gfs2: fix glock reference problem in gfs2_trans_remove_revoke Commit 9287c6452d2b fixed a situation in which gfs2 could use a glock after it had been freed. To do that, it temporarily added a new glock reference by calling gfs2_glock_hold in function gfs2_add_revoke. However, if the bd element was removed by gfs2_trans_remove_revoke, it failed to drop the additional reference. This patch adds logic to gfs2_trans_remove_revoke to properly drop the additional glock reference. Fixes: 9287c6452d2b ("gfs2: Fix occasional glock use-after-free") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher --- fs/gfs2/trans.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/gfs2/trans.c') diff --git a/fs/gfs2/trans.c b/fs/gfs2/trans.c index 35e3059255fe..9d4227330de4 100644 --- a/fs/gfs2/trans.c +++ b/fs/gfs2/trans.c @@ -262,6 +262,8 @@ void gfs2_trans_remove_revoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len) list_del_init(&bd->bd_list); gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke); sdp->sd_log_num_revoke--; + if (bd->bd_gl) + gfs2_glock_remove_revoke(bd->bd_gl); kmem_cache_free(gfs2_bufdata_cachep, bd); tr->tr_num_revoke--; if (--n == 0) -- cgit v1.2.3