Commit 034bbd806298 for kernel
commit 034bbd806298e9ba4197dd1587b0348ee30996ea
Author: Eric Dumazet <edumazet@google.com>
Date: Mon Feb 16 14:28:28 2026 +0000
icmp: prevent possible overflow in icmp_global_allow()
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 <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260216142832.3834174-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index e216b6df6331..eff8487c0aba 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -250,7 +250,8 @@ 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;