From 05d92723f99cf5c15ae74cc196193c2dbaa9a12c Mon Sep 17 00:00:00 2001
From: Kuniyuki Iwashima <kuniyu@amazon.com>
Date: Tue, 23 Aug 2022 10:46:51 -0700
Subject: [PATCH] net: Fix a data-race around sysctl_net_busy_poll.
[ Upstream commit c42b7cddea47503411bfb5f2f93a4154aaffa2d9 ]
While reading sysctl_net_busy_poll, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.
Fixes: 060212928670 ("net: add low latency socket poll")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/net/busy_poll.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/net/busy_poll.h b/include/net/busy_poll.h
index c4898fcbf923..f90f0021f5f2 100644
--- a/include/net/busy_poll.h
+++ b/include/net/busy_poll.h
@@ -33,7 +33,7 @@ extern unsigned int sysctl_net_busy_poll __read_mostly;
static inline bool net_busy_loop_on(void)
{
- return sysctl_net_busy_poll;
+ return READ_ONCE(sysctl_net_busy_poll);
}
static inline bool sk_can_busy_loop(const struct sock *sk)