ksmbd: fix control flow issues in sid_to_id()

Addresses-Coverity reported Control flow issues in sid_to_id()
/fs/ksmbd/smbacl.c: 277 in sid_to_id()
271
272	if (sidtype == SIDOWNER) {
273		kuid_t uid;
274		uid_t id;
275
276		id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
>>>	CID 1506810:  Control flow issues  (NO_EFFECT)
>>>	This greater-than-or-equal-to-zero comparison of an unsigned value
>>>	is always true. "id >= 0U".
277		if (id >= 0) {
278			/*
279			 * Translate raw sid into kuid in the server's user
280			 * namespace.
281			 */
282			uid = make_kuid(&init_user_ns, id);

Addresses-Coverity: ("Control flow issues")
Signed-off-by: Namjae Jeon <[email protected]>

smbacl.c

@@ -277,42 +277,38 @@ static int sid_to_id(struct user_namespace *user_ns,
 		uid_t id;
 
 		id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
-		if (id >= 0) {
-			/*
-			 * Translate raw sid into kuid in the server's user
-			 * namespace.
-			 */
-			uid = make_kuid(&init_user_ns, id);
+		/*
+		 * Translate raw sid into kuid in the server's user
+		 * namespace.
+		 */
+		uid = make_kuid(&init_user_ns, id);
 
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0)
-			/* If this is an idmapped mount, apply the idmapping. */
-			uid = kuid_from_mnt(user_ns, uid);
+		/* If this is an idmapped mount, apply the idmapping. */
+		uid = kuid_from_mnt(user_ns, uid);
 #endif
-			if (uid_valid(uid)) {
-				fattr->cf_uid = uid;
-				rc = 0;
-			}
+		if (uid_valid(uid)) {
+			fattr->cf_uid = uid;
+			rc = 0;
 		}
 	} else {
 		kgid_t gid;
 		gid_t id;
 
 		id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
-		if (id >= 0) {
-			/*
-			 * Translate raw sid into kgid in the server's user
-			 * namespace.
-			 */
-			gid = make_kgid(&init_user_ns, id);
+		/*
+		 * Translate raw sid into kgid in the server's user
+		 * namespace.
+		 */
+		gid = make_kgid(&init_user_ns, id);
 
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0)
-			/* If this is an idmapped mount, apply the idmapping. */
-			gid = kgid_from_mnt(user_ns, gid);
+		/* If this is an idmapped mount, apply the idmapping. */
+		gid = kgid_from_mnt(user_ns, gid);
 #endif
-			if (gid_valid(gid)) {
-				fattr->cf_gid = gid;
-				rc = 0;
-			}
+		if (gid_valid(gid)) {
+			fattr->cf_gid = gid;
+			rc = 0;
 		}
 	}