From: Eric Dumazet <edumazet@google.com>
Date: Thu, 4 Jun 2026 14:13:33 +0000 (+0000)
Subject: bridge: add a READ_ONCE() in br_timer_value()
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=032c8f6f21ee8d9c2ca2182f17960428be17dbb1;p=thirdparty%2Flinux.git

bridge: add a READ_ONCE() in br_timer_value()

br_timer_value() can be called locklessly, the expires field
could be changed concurrently.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260604141343.2124500-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/net/bridge/br_stp_timer.c b/net/bridge/br_stp_timer.c
index e5d453305381..83cc9c6a3943 100644
--- a/net/bridge/br_stp_timer.c
+++ b/net/bridge/br_stp_timer.c
@@ -160,5 +160,5 @@ void br_stp_port_timer_init(struct net_bridge_port *p)
 unsigned long br_timer_value(const struct timer_list *timer)
 {
 	return timer_pending(timer)
-		? jiffies_delta_to_clock_t(timer->expires - jiffies) : 0;
+		? jiffies_delta_to_clock_t(READ_ONCE(timer->expires) - jiffies) : 0;
 }