ipv4: use IS_ENABLED instead of ifdef

Checking for ifdef CONFIG_x fails if CONFIG_x=m. Use IS_ENABLED instead, which is true for both built-ins and modules. Otherwise, a > ip -4 route add 1.2.3.4/32 via inet6 fe80::2 dev eth1 fails with the message "Error: IPv6 support not enabled in kernel." if CONFIG_IPV6 is `m`. In the spirit of b812711. Fixes: d156626 ("ipv4: Allow ipv6 gateway with ipv4 routes") Cc: Kim Phillips <[email protected]> Signed-off-by: Florian Klink <[email protected]> Reviewed-by: David Ahern <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>
berg · Nov 18, 2020 · c09c8a2 · c09c8a2
1 parent 93be526
commit c09c8a2
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
@@ -696,7 +696,7 @@ int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
 		cfg->fc_gw4 = *((__be32 *)via->rtvia_addr);
 		break;
 	case AF_INET6:
-#ifdef CONFIG_IPV6
+#if IS_ENABLED(CONFIG_IPV6)
 		if (alen != sizeof(struct in6_addr)) {
 			NL_SET_ERR_MSG(extack, "Invalid IPv6 address in RTA_VIA");
 			return -EINVAL;