From: Baptiste Lepers baptiste.lepers@gmail.com
[ 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 --- net/core/sock_reuseport.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/core/sock_reuseport.c +++ b/net/core/sock_reuseport.c @@ -302,7 +302,7 @@ select_by_hash: 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;