summaryrefslogtreecommitdiff
path: root/fs/gfs2
diff options
context:
space:
mode:
authorBob Peterson <rpeterso@redhat.com>2021-02-25 19:11:09 +0300
committerAndreas Gruenbacher <agruenba@redhat.com>2021-03-07 19:04:55 +0300
commit1a5a2cfd34c17db73c53ef127272c8c1ae220485 (patch)
tree2239078721418ae2c4ec7acca720e9ec44326c9c /fs/gfs2
parenteb602521f43876b3f76c4686de596c9804977228 (diff)
downloadlinux-1a5a2cfd34c17db73c53ef127272c8c1ae220485.tar.xz
gfs2: fix use-after-free in trans_drain
This patch adds code to function trans_drain to remove drained bd elements from the ail lists, if queued, before freeing the bd. If we don't remove the bd from the ail, function ail_drain will try to reference the bd after it has been freed by trans_drain. Thanks to Andy Price for his analysis of the problem. Reported-by: Andy Price <anprice@redhat.com> Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Diffstat (limited to 'fs/gfs2')
-rw-r--r--fs/gfs2/log.c4
-rw-r--r--fs/gfs2/trans.c2
2 files changed, 6 insertions, 0 deletions
diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index 16937ebb2a3e..760af666576c 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -998,12 +998,16 @@ static void trans_drain(struct gfs2_trans *tr)
while (!list_empty(head)) {
bd = list_first_entry(head, struct gfs2_bufdata, bd_list);
list_del_init(&bd->bd_list);
+ if (!list_empty(&bd->bd_ail_st_list))
+ gfs2_remove_from_ail(bd);
kmem_cache_free(gfs2_bufdata_cachep, bd);
}
head = &tr->tr_databuf;
while (!list_empty(head)) {
bd = list_first_entry(head, struct gfs2_bufdata, bd_list);
list_del_init(&bd->bd_list);
+ if (!list_empty(&bd->bd_ail_st_list))
+ gfs2_remove_from_ail(bd);
kmem_cache_free(gfs2_bufdata_cachep, bd);
}
}
diff --git a/fs/gfs2/trans.c b/fs/gfs2/trans.c
index ab96cf0bf26b..63fec11ef2ce 100644
--- a/fs/gfs2/trans.c
+++ b/fs/gfs2/trans.c
@@ -169,6 +169,8 @@ static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
bd->bd_bh = bh;
bd->bd_gl = gl;
INIT_LIST_HEAD(&bd->bd_list);
+ INIT_LIST_HEAD(&bd->bd_ail_st_list);
+ INIT_LIST_HEAD(&bd->bd_ail_gl_list);
bh->b_private = bd;
return bd;
}