ipv4: fix a deadlock in ip_ra_control
Similar to commit 87e9f0315952
("ipv4: fix a potential deadlock in mcast getsockopt() path"),
there is a deadlock scenario for IP_ROUTER_ALERT too:
CPU0 CPU1
---- ----
lock(rtnl_mutex);
lock(sk_lock-AF_INET);
lock(rtnl_mutex);
lock(sk_lock-AF_INET);
Fix this by always locking RTNL first on all setsockopt() paths.
Note, after this patch ip_ra_lock is no longer needed either.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
3 files changed
