From: Baptiste Lepers baptiste.lepers@gmail.com
stable inclusion from linux-4.19.170 commit 4669452b4c66268a184a51c543b525533013c14e
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[ Upstream commit fd2ddef043592e7de80af53f47fa46fd3573086e ]
reuse->socks[] is modified concurrently by reuseport_add_sock. To prevent reading values that have not been fully initialized, only read the array up until the last known safe index instead of incorrectly re-reading the last index of the array.
Fixes: acdcecc61285f ("udp: correct reuseport selection with connected sockets") Signed-off-by: Baptiste Lepers baptiste.lepers@gmail.com Acked-by: Willem de Bruijn willemb@google.com Link: https://lore.kernel.org/r/20210107051110.12247-1-baptiste.lepers@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com
Signed-off-by: Aichun Li liaichun@huawei.com reviewed-by: wangxiaopeng wangxiaopeng7@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- net/core/sock_reuseport.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c index 9c85ef2b7e1d..375a3bbe6485 100644 --- a/net/core/sock_reuseport.c +++ b/net/core/sock_reuseport.c @@ -299,7 +299,7 @@ struct sock *reuseport_select_sock(struct sock *sk, i = j = reciprocal_scale(hash, socks); while (reuse->socks[i]->sk_state == TCP_ESTABLISHED) { i++; - if (i >= reuse->num_socks) + if (i >= socks) i = 0; if (i == j) goto out;