From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, David Ahern <dsahern@kernel.org>,
        Nicolas Dichtel <nicolas.dichtel@6wind.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.19 15/21] ipv6: Continue processing multipath route even if gateway attribute is invalid
Date:   Mon, 10 Jan 2022 08:23:16 +0100
Message-Id: <20220110071814.448271281@linuxfoundation.org>
In-Reply-To: <20220110071813.967414697@linuxfoundation.org>
References: <20220110071813.967414697@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: David Ahern <dsahern@kernel.org>

[ Upstream commit e30a845b0376eb51c9c94f56bbd53b2e08ba822f ]

ip6_route_multipath_del loop continues processing the multipath
attribute even if delete of a nexthop path fails. For consistency,
do the same if the gateway attribute is invalid.

Fixes: 1ff15a710a86 ("ipv6: Check attribute length for RTA_GATEWAY when deleting multipath route")
Signed-off-by: David Ahern <dsahern@kernel.org>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://lore.kernel.org/r/20220103171911.94739-1-dsahern@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/ipv6/route.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 1bc81be07ccda..8a437c20eeccd 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -4608,8 +4608,10 @@ static int ip6_route_multipath_del(struct fib6_config *cfg,
 			if (nla) {
 				err = fib6_gw_from_attr(&r_cfg.fc_gateway, nla,
 							extack);
-				if (err)
-					return err;
+				if (err) {
+					last_err = err;
+					goto next_rtnh;
+				}
 
 				r_cfg.fc_flags |= RTF_GATEWAY;
 			}
@@ -4618,6 +4620,7 @@ static int ip6_route_multipath_del(struct fib6_config *cfg,
 		if (err)
 			last_err = err;
 
+next_rtnh:
 		rtnh = rtnh_next(rtnh, &remaining);
 	}
 
-- 
2.34.1