From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shakeel Butt Subject: [PATCH] netfilter: account ebt_table_info to kmemcg Date: Fri, 28 Dec 2018 17:55:24 -0800 Message-ID: <20181229015524.222741-1-shakeelb@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: linux-mm@kvack.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, bridge@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Shakeel Butt , syzbot+7713f3aa67be76b1552c@syzkaller.appspotmail.com To: Pablo Neira Ayuso , Florian Westphal , Jozsef Kadlecsik , Roopa Prabhu , Nikolay Aleksandrov , Michal Hocko , Andrew Morton Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org The [ip,ip6,arp]_tables use x_tables_info internally and the underlying memory is already accounted to kmemcg. Do the same for ebtables. The syzbot, by using setsockopt(EBT_SO_SET_ENTRIES), was able to OOM the whole system from a restricted memcg, a potential DoS. Reported-by: syzbot+7713f3aa67be76b1552c@syzkaller.appspotmail.com Signed-off-by: Shakeel Butt --- net/bridge/netfilter/ebtables.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 491828713e0b..5e55cef0cec3 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -1137,14 +1137,16 @@ static int do_replace(struct net *net, const void __user *user, tmp.name[sizeof(tmp.name) - 1] = 0; countersize = COUNTER_OFFSET(tmp.nentries) * nr_cpu_ids; - newinfo = vmalloc(sizeof(*newinfo) + countersize); + newinfo = __vmalloc(sizeof(*newinfo) + countersize, GFP_KERNEL_ACCOUNT, + PAGE_KERNEL); if (!newinfo) return -ENOMEM; if (countersize) memset(newinfo->counters, 0, countersize); - newinfo->entries = vmalloc(tmp.entries_size); + newinfo->entries = __vmalloc(tmp.entries_size, GFP_KERNEL_ACCOUNT, + PAGE_KERNEL); if (!newinfo->entries) { ret = -ENOMEM; goto free_newinfo; -- 2.20.1.415.g653613c723-goog