Implement a function to kill dhclient process, sometimes it takes a little time to die, so use a sleep(1) there

2 files changed, 17 insertions, 7 deletions

diff --git a/etc/inc/interfaces.inc b/etc/inc/interfaces.inc
index 045ca17..a4390ad 100644
--- a/etc/inc/interfaces.inc
+++ b/etc/inc/interfaces.inc
@@ -1242,10 +1242,7 @@ function interface_bring_down($interface = "wan", $destroy = false, $ifacecfg =
 		}
 		break;
 	case "dhcp":
-		$pid = find_dhclient_process($realif);
-		if($pid)
-			posix_kill($pid, SIGTERM);
-		sleep(1);
+		kill_dhclient_process($realif);
 		unlink_if_exists("{$g['varetc_path']}/dhclient_{$interface}.conf");
 		if(does_interface_exist("$realif")) {
 			mwexec("/sbin/ifconfig " . escapeshellarg($realif) . " delete", true);
@@ -2801,6 +2798,21 @@ function find_dhclient_process($interface) {
 	return intval($pid);
 }
 
+function kill_dhclient_process($interface) {
+	if (empty($interface) || !does_interface_exist($interface))
+		return;
+
+	$i = 0;
+	while ((($pid = find_dhclient_process($interface)) != 0) && ($i < 3)) {
+		/* 3rd time make it die for sure */
+		$sig = ($i == 2 ? SIGKILL : SIGTERM);
+		posix_kill($pid, $sig);
+		sleep(1);
+		$i++;
+	}
+	unset($i);
+}
+
 function find_dhcp6c_process($interface) {
 	global $g;
 
diff --git a/usr/local/www/interfaces.php b/usr/local/www/interfaces.php
index e1d05c0..6aa0014 100644
--- a/usr/local/www/interfaces.php
+++ b/usr/local/www/interfaces.php
@@ -797,9 +797,7 @@ if ($_POST['apply']) {
 				$wancfg['if'] = $a_ppps[$pppid]['ports'];
 				unset($a_ppps[$pppid]);
 			} else if ($wancfg['ipaddr'] == "dhcp") {
-				$pid = find_dhclient_process($wancfg['if']);
-				if($pid)
-					posix_kill($pid, SIGTERM);
+				kill_dhclient_process($wancfg['if']);
 			}
 			if ($wancfg['ipaddrv6'] == "dhcp6") {
 				$pid = find_dhcp6c_process($wancfg['if']);