Patch "ipv4: Convert icmp_route_lookup() to dscp_t." has been added to the 6.1-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ipv4: Convert icmp_route_lookup() to dscp_t.

to the 6.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     ipv4-convert-icmp_route_lookup-to-dscp_t.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 58dc84dfc7fe7af13d34987cc888d07ad85f3155
Author: Guillaume Nault <gnault@xxxxxxxxxx>
Date:   Tue Oct 1 21:28:37 2024 +0200

    ipv4: Convert icmp_route_lookup() to dscp_t.
    
    [ Upstream commit 913c83a610bb7dd8e5952a2b4663e1feec0b5de6 ]
    
    Pass a dscp_t variable to icmp_route_lookup(), instead of a plain u8,
    to prevent accidental setting of ECN bits in ->flowi4_tos. Rename that
    variable ("tos" -> "dscp") to make the intent clear.
    
    While there, reorganise the function parameters to fill up horizontal
    space.
    
    Signed-off-by: Guillaume Nault <gnault@xxxxxxxxxx>
    Reviewed-by: David Ahern <dsahern@xxxxxxxxxx>
    Link: https://patch.msgid.link/294fead85c6035bcdc5fcf9a6bb4ce8798c45ba1.1727807926.git.gnault@xxxxxxxxxx
    Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
    Stable-dep-of: 27843ce6ba3d ("ipvlan: ensure network headers are in skb linear part")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index a154339845dd4..855fcef829e2c 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -484,13 +484,11 @@ static struct net_device *icmp_get_route_lookup_dev(struct sk_buff *skb)
 	return route_lookup_dev;
 }
 
-static struct rtable *icmp_route_lookup(struct net *net,
-					struct flowi4 *fl4,
+static struct rtable *icmp_route_lookup(struct net *net, struct flowi4 *fl4,
 					struct sk_buff *skb_in,
-					const struct iphdr *iph,
-					__be32 saddr, u8 tos, u32 mark,
-					int type, int code,
-					struct icmp_bxm *param)
+					const struct iphdr *iph, __be32 saddr,
+					dscp_t dscp, u32 mark, int type,
+					int code, struct icmp_bxm *param)
 {
 	struct net_device *route_lookup_dev;
 	struct rtable *rt, *rt2;
@@ -503,7 +501,7 @@ static struct rtable *icmp_route_lookup(struct net *net,
 	fl4->saddr = saddr;
 	fl4->flowi4_mark = mark;
 	fl4->flowi4_uid = sock_net_uid(net, NULL);
-	fl4->flowi4_tos = tos & INET_DSCP_MASK;
+	fl4->flowi4_tos = inet_dscp_to_dsfield(dscp);
 	fl4->flowi4_proto = IPPROTO_ICMP;
 	fl4->fl4_icmp_type = type;
 	fl4->fl4_icmp_code = code;
@@ -551,7 +549,7 @@ static struct rtable *icmp_route_lookup(struct net *net,
 		orefdst = skb_in->_skb_refdst; /* save old refdst */
 		skb_dst_set(skb_in, NULL);
 		err = ip_route_input(skb_in, fl4_dec.daddr, fl4_dec.saddr,
-				     tos, rt2->dst.dev);
+				     inet_dscp_to_dsfield(dscp), rt2->dst.dev);
 
 		dst_release(&rt2->dst);
 		rt2 = skb_rtable(skb_in);
@@ -747,8 +745,9 @@ void __icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info,
 	ipc.opt = &icmp_param.replyopts.opt;
 	ipc.sockc.mark = mark;
 
-	rt = icmp_route_lookup(net, &fl4, skb_in, iph, saddr, tos, mark,
-			       type, code, &icmp_param);
+	rt = icmp_route_lookup(net, &fl4, skb_in, iph, saddr,
+			       inet_dsfield_to_dscp(tos), mark, type, code,
+			       &icmp_param);
 	if (IS_ERR(rt))
 		goto out_unlock;