From: Felix Fietkau <nbd@nbd.name>
Date: Thu, 25 Aug 2022 19:09:24 +0000 (+0200)
Subject: interface: fix use-after-free bug when rewriting resolv.conf
X-Git-Url: http://git.openwrt.org/b27977b41be6d010c9d5a8fc67e5e48135f11aae.?a=commitdiff_plain;h=76d2d41b7355e02f95fbfa79affbd232fb090595;p=project%2Fnetifd.git

interface: fix use-after-free bug when rewriting resolv.conf

After the call to interface_handle_config_change, the iface pointer will no
longer be valid if the interface has been deleted from the config

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---

diff --git a/interface.c b/interface.c
index 255ce84..89654f9 100644
--- a/interface.c
+++ b/interface.c
@@ -771,12 +771,13 @@ interface_proto_event_cb(struct interface_proto_state *state, enum interface_pro
 
 		netifd_log_message(L_NOTICE, "Interface '%s' is now down\n", iface->name);
 		mark_interface_down(iface);
+		interface_write_resolv_conf(iface->jail);
 		if (iface->main_dev.dev)
 			device_release(&iface->main_dev);
 		if (iface->l3_dev.dev)
 			device_remove_user(&iface->l3_dev);
 		interface_handle_config_change(iface);
-		break;
+		return;
 	case IFPEV_LINK_LOST:
 		if (iface->state != IFS_UP)
 			return;