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 e5d453305381baa34225a144ac99e98f2a62d810..83cc9c6a3943508eb94d20ddc1b7e737a58d7abb 100644 (file)
--- 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;
 }