FAILED: patch "[PATCH] net/smc: Fix loop in smc_listen" failed to apply to 4.14-stable tree

The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 9ebb0c4b27a6158303b791b5b91e66d7665ee30e Mon Sep 17 00:00:00 2001
From: Guo DaXing <[email protected]>
Date: Wed, 24 Nov 2021 13:32:38 +0100
Subject: [PATCH] net/smc: Fix loop in smc_listen

The kernel_listen function in smc_listen will fail when all the available ports are occupied. At this point smc->clcsock->sk->sk_data_ready has been changed to smc_clcsock_data_ready. When we call smc_listen again, now both smc->clcsock->sk->sk_data_ready and smc->clcsk_data_ready point to the smc_clcsock_data_ready function.

The smc_clcsock_data_ready() function calls lsmc->clcsk_data_ready which now points to itself resulting in an infinite loop.

This patch restores smc->clcsock->sk->sk_data_ready with the old value.

index 2692cba5a7b6..4b62c925a13e 100644
@@ -2134,8 +2134,10 @@ static int smc_listen(struct socket *sock, int backlog)
 	smc->clcsock->sk->sk_user_data =
 		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
 	rc = kernel_listen(smc->clcsock, backlog);
-	if (rc)
+	if (rc) {
+		smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready;
 		goto out;
+	}
 	sk->sk_max_ack_backlog = backlog;
 	sk->sk_ack_backlog = 0;
 	sk->sk_state = SMC_LISTEN;