lib/sub.c: subsystem(): Prevent -Wstrict-overflow diagnostic

The compiler thinks ++depth within the conditional could overflow the
type, because it doesn't see that exit(3) will terminate the program.
Let's make it easy for the compiler, and only increment the value if
we're not going to call exit(3).

Signed-off-by: Alejandro Colomar <[email protected]>

Author: alejandro-colomar

lib/sub.c

@@ -34,12 +34,13 @@ void subsystem (const struct passwd *pw)
 	/*
 	 * Prevent endless loop on misconfigured systems.
 	 */
-	if (++depth > MAX_DEPTH) {
+	if (depth >= MAX_DEPTH) {
 		printf (_("Maximum subsystem depth reached\n"));
 		SYSLOG ((LOG_WARN, MAX_SUBROOT2));
 		closelog ();
 		exit (EXIT_FAILURE);
 	}
+	depth++;
 
 	/*
 	 * The new root directory must begin with a "/" character.