4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Cong Wang xiyou.wangcong@gmail.com
commit ba7cd5d95f25cc6005f687dabdb4e7a6063adda9 upstream.
xt_cgroup_info_v1->priv is an internal pointer only used for kernel, we should not trust what user-space provides.
Reported-by: syzbot+4fbcfcc0d2e6592bd641@syzkaller.appspotmail.com Fixes: c38c4597e4bf ("netfilter: implement xt_cgroup cgroup2 path match") Cc: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Cong Wang xiyou.wangcong@gmail.com Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/netfilter/xt_cgroup.c | 1 + 1 file changed, 1 insertion(+)
--- a/net/netfilter/xt_cgroup.c +++ b/net/netfilter/xt_cgroup.c @@ -52,6 +52,7 @@ static int cgroup_mt_check_v1(const stru return -EINVAL; }
+ info->priv = NULL; if (info->has_path) { cgrp = cgroup_get_from_path(info->path); if (IS_ERR(cgrp)) {