inet: lockless getsockopt(IP_MTU)

sk_dst_get() does not require socket lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet
2023-09-22 03:42:18 +00:00
committed by David S. Miller
parent a4725d0d89
commit 3523bc91e4

View File

@@ -1620,13 +1620,6 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname,
return -EFAULT;
return 0;
}
}
if (needs_rtnl)
rtnl_lock();
sockopt_lock_sock(sk);
switch (optname) {
case IP_MTU:
{
struct dst_entry *dst;
@@ -1636,12 +1629,17 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname,
val = dst_mtu(dst);
dst_release(dst);
}
if (!val) {
sockopt_release_sock(sk);
if (!val)
return -ENOTCONN;
}
break;
goto copyval;
}
}
if (needs_rtnl)
rtnl_lock();
sockopt_lock_sock(sk);
switch (optname) {
case IP_UNICAST_IF:
val = (__force int)htonl((__u32) inet->uc_index);
break;