[PATCH 4.18 27/53] net/smc: fix sizeof to int comparison

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: YueHaibing <yuehaibing@xxxxxxxxxx>

[ Upstream commit 381897798a94065ffcad0772eecdc6b04a7ff23d ]

Comparing an int to a size, which is unsigned, causes the int to become
unsigned, giving the wrong result. kernel_sendmsg can return a negative
error code.

Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
Signed-off-by: Ursula Braun <ubraun@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/smc/smc_clc.c |   14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -405,14 +405,12 @@ int smc_clc_send_proposal(struct smc_soc
 	vec[i++].iov_len = sizeof(trl);
 	/* due to the few bytes needed for clc-handshake this cannot block */
 	len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen);
-	if (len < sizeof(pclc)) {
-		if (len >= 0) {
-			reason_code = -ENETUNREACH;
-			smc->sk.sk_err = -reason_code;
-		} else {
-			smc->sk.sk_err = smc->clcsock->sk->sk_err;
-			reason_code = -smc->sk.sk_err;
-		}
+	if (len < 0) {
+		smc->sk.sk_err = smc->clcsock->sk->sk_err;
+		reason_code = -smc->sk.sk_err;
+	} else if (len < (int)sizeof(pclc)) {
+		reason_code = -ENETUNREACH;
+		smc->sk.sk_err = -reason_code;
 	}
 
 	return reason_code;