ipv6: fix IPV6_ADDRFORM operation logic

Socket option IPV6_ADDRFORM supports UDP/UDPLITE and TCP at present. Previously the checking logic looks like: if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE) do_some_check; else if (sk->sk_protocol != IPPROTO_TCP) break; After commit b6f6118 ("ipv6: restrict IPV6_ADDRFORM operation"), TCP was blocked as the logic changed to: if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE) do_some_check; else if (sk->sk_protocol == IPPROTO_TCP) do_some_check; break; else break; Then after commit 82c9ae4 ("ipv6: fix restrict IPV6_ADDRFORM operation") UDP/UDPLITE were blocked as the logic changed to: if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE) do_some_check; if (sk->sk_protocol == IPPROTO_TCP) do_some_check; if (sk->sk_protocol != IPPROTO_TCP) break; Fix it by using Eric's code and simply remove the break in TCP check, which looks like: if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE) do_some_check; else if (sk->sk_protocol == IPPROTO_TCP) do_some_check; else break; Fixes: 82c9ae4 ("ipv6: fix restrict IPV6_ADDRFORM operation") Signed-off-by: Hangbin Liu <[email protected]> Signed-off-by: David S. Miller <[email protected]>
zandrey · Jun 1, 2020 · 79a1f0c · 79a1f0c
1 parent 4c21daa
commit 79a1f0c
Showing 1 changed file with 7 additions and 6 deletions.
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
@@ -218,14 +218,15 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 					retv = -EBUSY;
 					break;
 				}
-			}
-			if (sk->sk_protocol == IPPROTO_TCP &&
-			    sk->sk_prot != &tcpv6_prot) {
-				retv = -EBUSY;
+			} else if (sk->sk_protocol == IPPROTO_TCP) {
+				if (sk->sk_prot != &tcpv6_prot) {
+					retv = -EBUSY;
+					break;
+				}
+			} else {
 				break;
 			}
-			if (sk->sk_protocol != IPPROTO_TCP)
-				break;
+
 			if (sk->sk_state != TCP_ESTABLISHED) {
 				retv = -ENOTCONN;
 				break;