check_snmp: Fix potential buffer overflow - enforce MAX_OIDS limit (John A. Barbuto)

plugins/check_snmp.c

@@ -527,9 +527,8 @@ process_arguments (int argc, char **argv)
 					needmibs = TRUE;
 			}
 			oids = calloc(MAX_OIDS, sizeof (char *));
-			for (ptr = strtok(optarg, ", "); ptr != NULL; ptr = strtok(NULL, ", ")) {
+			for (ptr = strtok(optarg, ", "); ptr != NULL && j < MAX_OIDS; ptr = strtok(NULL, ", "), j++) {
 				oids[j] = strdup(ptr);
-				j++;
 			}
 			numoids = j;
 			if (c == 'E' || c == 'e') {