Revert "ipv4: fix memory leaks in ip_cmsg_send() callers"

This reverts commit 91948309.

There is only when ip_options_get() return zero need to free.
It already called kfree() when return error.

Fixes: 91948309 ("ipv4: fix memory leaks in ip_cmsg_send() callers")
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/ip_sockglue.c

@@ -279,7 +279,7 @@ int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc,
 		case IP_RETOPTS:
 			err = cmsg->cmsg_len - sizeof(struct cmsghdr);
 
-			/* Our caller is responsible for freeing ipc->opt */
+			/* Our caller is responsible for freeing ipc->opt when err = 0 */
 			err = ip_options_get(net, &ipc->opt,
 					     KERNEL_SOCKPTR(CMSG_DATA(cmsg)),
 					     err < 40 ? err : 40);

net/ipv4/ping.c

@@ -727,10 +727,9 @@ static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
 	if (msg->msg_controllen) {
 		err = ip_cmsg_send(sk, msg, &ipc, false);
-		if (unlikely(err)) {
-			kfree(ipc.opt);
+		if (unlikely(err))
 			return err;
-		}
+
 		if (ipc.opt)
 			free = 1;
 	}

net/ipv4/raw.c

@@ -562,10 +562,9 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
 	if (msg->msg_controllen) {
 		err = ip_cmsg_send(sk, msg, &ipc, false);
-		if (unlikely(err)) {
-			kfree(ipc.opt);
+		if (unlikely(err))
 			goto out;
-		}
+
 		if (ipc.opt)
 			free = 1;
 	}

net/ipv4/udp.c

@@ -1122,10 +1122,9 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 		if (err > 0)
 			err = ip_cmsg_send(sk, msg, &ipc,
 					   sk->sk_family == AF_INET6);
-		if (unlikely(err < 0)) {
-			kfree(ipc.opt);
+		if (unlikely(err < 0))
 			return err;
-		}
+
 		if (ipc.opt)
 			free = 1;
 		connected = 0;