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+bad6e32808a3a97b1...@syzkaller.appspotmail.com
Fixes: 2638eb8b50cf ("net: ipv4: provide __rcu annotation for ifa_list")
Signed-off-by: Florian Westphal <f...@strlen.de>
---
net/ipv4/devinet.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index ebaea05b4033..ed2e2dc745cd 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -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;
--
2.21.0
