net: ipv4: fix rcu lockdep splat due to wrong annotation

syzbot triggered following splat when strict netlink
validation is enabled:

net/ipv4/devinet.c:1766 suspicious rcu_dereference_check() usage!

This occurs because we hold RTNL mutex, but no rcu read lock.
The second call site holds both, so just switch to the _rtnl variant.

Reported-by: syzbot+bad6e32808a3a97b1515@syzkaller.appspotmail.com
Fixes: 2638eb8b50 ("net: ipv4: provide __rcu annotation for ifa_list")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Florian Westphal 2019-06-03 22:41:44 +02:00 committed by David S. Miller
parent ae95f9c1a5
commit d3e6e285ff

View file

@ -1763,7 +1763,7 @@ static int in_dev_dump_addr(struct in_device *in_dev, struct sk_buff *skb,
int ip_idx = 0;
int err;
in_dev_for_each_ifa_rcu(ifa, in_dev) {
in_dev_for_each_ifa_rtnl(ifa, in_dev) {
if (ip_idx < s_ip_idx) {
ip_idx++;
continue;