From: Eric Dumazet <edumazet@google.com> stable inclusion from stable-v5.10.137 commit b7325b27d8697a64858f673bbaba0741cff740cc category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit fdb5fd7f736ec7ae9fb36d2842ea6d9ebc4e7269 ] inet_request_bound_dev_if() reads sk->sk_bound_dev_if twice while listener socket is not locked. Another cpu could change this field under us. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Wei Li <liwei391@huawei.com> --- include/net/inet_sock.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index 9a286c943871..ad4ff63bc47a 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -118,14 +118,15 @@ static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb) static inline int inet_request_bound_dev_if(const struct sock *sk, struct sk_buff *skb) { + int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); #ifdef CONFIG_NET_L3_MASTER_DEV struct net *net = sock_net(sk); - if (!sk->sk_bound_dev_if && net->ipv4.sysctl_tcp_l3mdev_accept) + if (!bound_dev_if && net->ipv4.sysctl_tcp_l3mdev_accept) return l3mdev_master_ifindex_by_index(net, skb->skb_iif); #endif - return sk->sk_bound_dev_if; + return bound_dev_if; } static inline int inet_sk_bound_l3mdev(const struct sock *sk) -- 2.20.1