From 545714e99ba1a34a2d48ecf69d7ba5246b260ce5 Mon Sep 17 00:00:00 2001 From: Jason Xing Date: Mon, 4 Mar 2024 16:20:46 +0800 Subject: [PATCH] netrom: Fix data-races around sysctl_net_busy_read [ Upstream commit d380ce70058a4ccddc3e5f5c2063165dc07672c6 ] 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 Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/netrom/af_netrom.c | 2 +- net/netrom/nr_in.c | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c index 376b6af43..37d0bf6ca 100755 --- a/net/netrom/af_netrom.c +++ b/net/netrom/af_netrom.c @@ -954,7 +954,7 @@ int nr_rx_frame(struct sk_buff *skb, struct net_device *dev) * G8PZT's Xrouter which is sending packets with command type 7 * as an extension of the protocol. */ - if (sysctl_netrom_reset_circuit && + if (READ_ONCE(sysctl_netrom_reset_circuit) && (frametype != NR_RESET || flags != 0)) nr_transmit_reset(skb, 1); diff --git a/net/netrom/nr_in.c b/net/netrom/nr_in.c index 69e58906c..034f79d11 100755 --- a/net/netrom/nr_in.c +++ b/net/netrom/nr_in.c @@ -97,7 +97,7 @@ static int nr_state1_machine(struct sock *sk, struct sk_buff *skb, break; case NR_RESET: - if (sysctl_netrom_reset_circuit) + if (READ_ONCE(sysctl_netrom_reset_circuit)) nr_disconnect(sk, ECONNRESET); break; @@ -128,7 +128,7 @@ static int nr_state2_machine(struct sock *sk, struct sk_buff *skb, break; case NR_RESET: - if (sysctl_netrom_reset_circuit) + if (READ_ONCE(sysctl_netrom_reset_circuit)) nr_disconnect(sk, ECONNRESET); break; @@ -263,7 +263,7 @@ static int nr_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype break; case NR_RESET: - if (sysctl_netrom_reset_circuit) + if (READ_ONCE(sysctl_netrom_reset_circuit)) nr_disconnect(sk, ECONNRESET); break;