From: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> [ Upstream commit d2efabce81db7eed1c98fa1a3f203f0edd738ac3 ] While reading sysctl_icmp_errors_use_inbound_ifaddr, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1c2fb7f93cb2 ("[IPV4]: Sysctl configurable icmp error source address.") Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/ipv4/icmp.c | 2 +- net/ipv4/sysctl_net_ipv4.c | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 1a061d10949f..37ba5f042908 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -693,7 +693,7 @@ void __icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info, rcu_read_lock(); if (rt_is_input_route(rt) && - net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr) + READ_ONCE(net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr)) dev = dev_get_by_index_rcu(net, inet_iif(skb_in)); if (dev) diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index 4cf2a6f560d4..33e65e79e46e 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -639,6 +639,8 @@ static struct ctl_table ipv4_net_table[] = { .maxlen = sizeof(u8), .mode = 0644, .proc_handler = proc_dou8vec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE }, { .procname = "icmp_ratelimit", -- 2.35.1