rxrpc: Check address length before reading srx_service field

KMSAN will complain if valid address length passed to bind() is shorter
than sizeof(struct sockaddr_rxrpc) bytes.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index 96f2952bbdfd..c54dce3ca0dd 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -135,7 +135,7 @@ static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
         struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *)saddr;
         struct rxrpc_local *local;
         struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
-        u16 service_id = srx->srx_service;
+        u16 service_id;
         int ret;
 
         _enter("%p,%p,%d", rx, saddr, len);
@@ -143,6 +143,7 @@ static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
         ret = rxrpc_validate_address(rx, srx, len);
         if (ret < 0)
                 goto error;
+        service_id = srx->srx_service;
 
         lock_sock(&rx->sk);