From: Felix Fietkau <nbd@nbd.name>
Date: Thu, 11 Aug 2016 17:36:09 +0000 (+0200)
Subject: Prevent premature device free in interface_claim_device
X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fnetifd.git;a=commitdiff_plain;h=c8a5f1ae361ab61192be6085c29d977eb73a05f5;hp=cec1ce296eede81dc62628fce33b8cc216727b17

Prevent premature device free in interface_claim_device

interface_set_device_config can trigger a device free (for example
if the device is here only present in a bridge), which renders dev
invalid and leads to segfault. Add a lock to prevent this and
clean-up the code for readability.

Signed-off-by: Gino Peeters <peeters.gino@gmail.com>
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---

diff --git a/interface.c b/interface.c
index 0b9893c..71e2ecc 100644
--- a/interface.c
+++ b/interface.c
@@ -586,6 +586,8 @@ interface_claim_device(struct interface *iface)
 	if (iface->parent_iface.iface)
 		interface_remove_user(&iface->parent_iface);
 
+	device_lock();
+
 	if (iface->parent_ifname) {
 		parent = vlist_find(&interfaces, iface->parent_ifname, parent, node);
 		iface->parent_iface.cb = interface_alias_cb;
@@ -601,6 +603,8 @@ interface_claim_device(struct interface *iface)
 	if (dev)
 		interface_set_main_dev(iface, dev);
 
+	device_unlock();
+
 	if (iface->proto_handler->flags & PROTO_FLAG_INIT_AVAILABLE)
 		interface_set_available(iface, true);
 }