[PATCH 5.4 14/51] netrom: Fix a data-race around sysctl_netrom_obsolescence_count_initialiser

From: Sasha Levin
Date: Wed Mar 13 2024 - 14:06:51 EST


From: Jason Xing <kernelxing@xxxxxxxxxxx>

[ Upstream commit cfd9f4a740f772298308b2e6070d2c744fb5cf79 ]

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>
---
net/netrom/nr_route.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c
index b7be86d41d965..7859217249124 100644
--- a/net/netrom/nr_route.c
+++ b/net/netrom/nr_route.c
@@ -763,7 +763,7 @@ int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
if (ax25 != NULL) {
ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
ax25->ax25_dev->dev, 0,
- sysctl_netrom_obsolescence_count_initialiser);
+ READ_ONCE(sysctl_netrom_obsolescence_count_initialiser));
if (ret)
return ret;
}
--
2.43.0