From: Guillaume Nault gnault@redhat.com
stable inclusion from linux-4.19.231 commit bbf7a1a2fc64d89896ba5eba494a40ca151a2675
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commit 23e7b1bfed61e301853b5e35472820d919498278 upstream.
Similar to commit 94e2238969e8 ("xfrm4: strip ECN bits from tos field"), clear the ECN bits from iph->tos when setting ->flowi4_tos. This ensures that the last bit of ->flowi4_tos is cleared, so ip_route_output_key_hash() isn't going to restrict the scope of the route lookup.
Use ~INET_ECN_MASK instead of IPTOS_RT_MASK, because we have no reason to clear the high order bits.
Found by code inspection, compile tested only.
Fixes: 4da3089f2b58 ("[IPSEC]: Use TOS when doing tunnel lookups") Signed-off-by: Guillaume Nault gnault@redhat.com Signed-off-by: Jakub Kicinski kuba@kernel.org [sudip: manually backport to previous location] Signed-off-by: Sudip Mukherjee sudipm.mukherjee@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yongqiang Liu liuyongqiang13@huawei.com Signed-off-by: Laibin Qiu qiulaibin@huawei.com --- net/ipv4/xfrm4_policy.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c index 1e5e2e4be0b2..e85b5f57d3e9 100644 --- a/net/ipv4/xfrm4_policy.c +++ b/net/ipv4/xfrm4_policy.c @@ -17,6 +17,7 @@ #include <net/xfrm.h> #include <net/ip.h> #include <net/l3mdev.h> +#include <net/inet_ecn.h>
static struct dst_entry *__xfrm4_dst_lookup(struct net *net, struct flowi4 *fl4, int tos, int oif, @@ -126,7 +127,7 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse) fl4->flowi4_proto = iph->protocol; fl4->daddr = reverse ? iph->saddr : iph->daddr; fl4->saddr = reverse ? iph->daddr : iph->saddr; - fl4->flowi4_tos = iph->tos; + fl4->flowi4_tos = iph->tos & ~INET_ECN_MASK;
if (!ip_is_fragment(iph)) { switch (iph->protocol) {