From 89ebdf2d4fb4fc57349fba42365971e0f7d431b1 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 16 Feb 2026 14:28:28 +0000 Subject: icmp: prevent possible overflow in icmp_global_allow() [ Upstream commit 034bbd806298e9ba4197dd1587b0348ee30996ea ] Following expression can overflow if sysctl_icmp_msgs_per_sec is big enough. sysctl_icmp_msgs_per_sec * delta / HZ; Fixes: 4cdf507d5452 ("icmp: add a global rate limitation") Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260216142832.3834174-2-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/icmp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index d2c7509135a3..374ec3aba66e 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -247,7 +247,8 @@ bool icmp_global_allow(struct net *net) if (delta < HZ / 50) return false; - incr = READ_ONCE(net->ipv4.sysctl_icmp_msgs_per_sec) * delta / HZ; + incr = READ_ONCE(net->ipv4.sysctl_icmp_msgs_per_sec); + incr = div_u64((u64)incr * delta, HZ); if (!incr) return false; -- cgit v1.2.3