From 1e443e2a01639f1d5d8c6a5569094b0204b193e0 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Wed, 2 Nov 2022 15:33:37 +0800 Subject: [PATCH] icmp: Fix data-races around sysctl. stable inclusion from stable-v5.10.132 commit e088ceb73c24ab4774da391d54a6426f4bfaefce category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5YS3T Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=e088ceb73c24ab4774da391d54a6426f4bfaefce -------------------------------- [ Upstream commit 48d7ee321ea5182c6a70782aa186422a70e67e22 ] While reading icmp sysctl variables, they can be changed concurrently. So, we need to add READ_ONCE() to avoid data-races. Fixes: 4cdf507d5452 ("icmp: add a global rate limitation") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Zheng Zengkai Acked-by: Xie XiuQi --- net/ipv4/icmp.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index cd65d3146c30..f22c0d55f479 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -261,11 +261,12 @@ bool icmp_global_allow(void) spin_lock(&icmp_global.lock); delta = min_t(u32, now - icmp_global.stamp, HZ); if (delta >= HZ / 50) { - incr = sysctl_icmp_msgs_per_sec * delta / HZ ; + incr = READ_ONCE(sysctl_icmp_msgs_per_sec) * delta / HZ; if (incr) WRITE_ONCE(icmp_global.stamp, now); } - credit = min_t(u32, icmp_global.credit + incr, sysctl_icmp_msgs_burst); + credit = min_t(u32, icmp_global.credit + incr, + READ_ONCE(sysctl_icmp_msgs_burst)); if (credit) { /* We want to use a credit of one in average, but need to randomize * it for security reasons. -- GitLab