This is a note to let you know that I've just added the patch titled netrom: Fix a data-race around sysctl_netrom_routing_control to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: netrom-fix-a-data-race-around-sysctl_netrom_routing_.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 5f033f0b1bf701c199f97fec41d87de89bae6271 Author: Jason Xing <kernelxing@xxxxxxxxxxx> Date: Mon Mar 4 16:20:44 2024 +0800 netrom: Fix a data-race around sysctl_netrom_routing_control [ Upstream commit b5dffcb8f71bdd02a4e5799985b51b12f4eeaf76 ] We need to protect the reader reading the sysctl value because the value can be changed concurrently. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Jason Xing <kernelxing@xxxxxxxxxxx> Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c index 8a5375e1dcc77..88c59bd0f7397 100644 --- a/net/netrom/nr_route.c +++ b/net/netrom/nr_route.c @@ -777,7 +777,7 @@ int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25) return ret; } - if (!sysctl_netrom_routing_control && ax25 != NULL) + if (!READ_ONCE(sysctl_netrom_routing_control) && ax25 != NULL) return 0; /* Its Time-To-Live has expired */