ipv6: Check attribute length for RTA_GATEWAY when deleting multipath route

dsahern · davem330 · commit 1ff15a710a86 · 2021-12-31T14:31:59.000Z
Make sure RTA_GATEWAY for IPv6 multipath route has enough bytes to hold an IPv6 address. Fixes: 6b9ea5a ("ipv6: fix multipath route replace error recovery") Signed-off-by: David Ahern <dsahern@kernel.org> Cc: Roopa Prabhu <roopa@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
@@ -5453,7 +5453,11 @@ static int ip6_route_multipath_del(struct fib6_config *cfg,
 
 			nla = nla_find(attrs, attrlen, RTA_GATEWAY);
 			if (nla) {
-				nla_memcpy(&r_cfg.fc_gateway, nla, 16);
+				err = fib6_gw_from_attr(&r_cfg.fc_gateway, nla,
+							extack);
+				if (err)
+					return err;
+
 				r_cfg.fc_flags |= RTF_GATEWAY;
 			}
 		}

Original file line number	Diff line number	Diff line change
`@@ -5453,7 +5453,11 @@ static int ip6_route_multipath_del(struct fib6_config *cfg,`
`5453`	`5453`
`5454`	`5454`	`nla = nla_find(attrs, attrlen, RTA_GATEWAY);`
`5455`	`5455`	`if (nla) {`
`5456`		`- nla_memcpy(&r_cfg.fc_gateway, nla, 16);`
	`5456`	`+ err = fib6_gw_from_attr(&r_cfg.fc_gateway, nla,`
	`5457`	`+ extack);`
	`5458`	`+ if (err)`
	`5459`	`+ return err;`
	`5460`	`+`
`5457`	`5461`	`r_cfg.fc_flags \|= RTF_GATEWAY;`
`5458`	`5462`	`}`
`5459`	`5463`	`}`