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+7713f3aa67be76b15...@syzkaller.appspotmail.com
Signed-off-by: Shakeel Butt <shake...@google.com>
---
 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

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