[PATCH net-next 2/4] net: bridge: mcast: fix memcpy with u64_stats
From: David Yang <mmyangfl@gmail.com>
Date: 2026-01-20 09:22:51
Also in:
bridge, lkml
Subsystem:
ethernet bridge, networking [general], the rest · Maintainers:
Nikolay Aleksandrov, Ido Schimmel, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
On 64bit arches, struct u64_stats_sync is empty and provides no help against load/store tearing. memcpy() should not be considered atomic against u64 values. Use u64_stats_copy() instead. Signed-off-by: David Yang <mmyangfl@gmail.com> --- net/bridge/br_multicast.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index d55a4ab87837..dccae08b4f4c 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c@@ -5201,7 +5201,7 @@ void br_multicast_get_stats(const struct net_bridge *br, do { start = u64_stats_fetch_begin(&cpu_stats->syncp); - memcpy(&temp, &cpu_stats->mstats, sizeof(temp)); + u64_stats_copy(&temp, &cpu_stats->mstats, sizeof(temp)); } while (u64_stats_fetch_retry(&cpu_stats->syncp, start)); mcast_stats_add_dir(tdst.igmp_v1queries, temp.igmp_v1queries);
--
2.51.0