From 149bc7834d6fde88e896d61bd98fff9027681581 Mon Sep 17 00:00:00 2001 From: Sriram Yagnaraman Date: Thu, 31 Aug 2023 10:03:30 +0200 Subject: [PATCH] ipv4: ignore dst hint for multipath routes [ Upstream commit 6ac66cb03ae306c2e288a9be18226310529f5b25 ] Route hints when the nexthop is part of a multipath group causes packets in the same receive batch to be sent to the same nexthop irrespective of the multipath hash of the packet. So, do not extract route hint for packets whose destination is part of a multipath group. A new SKB flag IPSKB_MULTIPATH is introduced for this purpose, set the flag when route is looked up in ip_mkroute_input() and use it in ip_extract_route_hint() to check for the existence of the flag. Fixes: 02b24941619f ("ipv4: use dst hint for ipv4 list receive") Signed-off-by: Sriram Yagnaraman Reviewed-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- include/net/ip.h | 1 + net/ipv4/ip_input.c | 3 ++- net/ipv4/route.c | 1 + 3 files changed, 4 insertions(+), 1 deletion(-) diff --git a/include/net/ip.h b/include/net/ip.h index fc05e016be06..e1a93c339109 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -56,6 +56,7 @@ struct inet_skb_parm { #define IPSKB_FRAG_PMTU BIT(6) #define IPSKB_L3SLAVE BIT(7) #define IPSKB_NOPOLICY BIT(8) +#define IPSKB_MULTIPATH BIT(9) u16 frag_max_size; }; diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index 124bf8fdf924..5d0bc0dbdb4d 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -581,7 +581,8 @@ static void ip_sublist_rcv_finish(struct list_head *head) static struct sk_buff *ip_extract_route_hint(const struct net *net, struct sk_buff *skb, int rt_type) { - if (fib4_has_custom_rules(net) || rt_type == RTN_BROADCAST) + if (fib4_has_custom_rules(net) || rt_type == RTN_BROADCAST || + IPCB(skb)->flags & IPSKB_MULTIPATH) return NULL; return skb; diff --git a/net/ipv4/route.c b/net/ipv4/route.c index ca59b61fd3a3..bc6240d327a8 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2151,6 +2151,7 @@ static int ip_mkroute_input(struct sk_buff *skb, int h = fib_multipath_hash(res->fi->fib_net, NULL, skb, hkeys); fib_select_multipath(res, h); + IPCB(skb)->flags |= IPSKB_MULTIPATH; } #endif