0003316: After ifconfig wlan0 down, ifconfig wlan0 will no longer revive wireless interface. - Kali Linux Bug Tracker

ID	Project	Category	View Status	Date Submitted	Last Update

0003316	Kali Linux	General Bug	public	2016-05-28 18:43	2025-07-14 09:36

Reporter	dner	Assigned To	rhertzog
Priority	normal	Severity	minor	Reproducibility	always
Status	closed	Resolution	no change required
Product Version	2016.1

Summary	0003316: After ifconfig wlan0 down, ifconfig wlan0 will no longer revive wireless interface.
Description	Discovered when using macchanger. I have never encountered this issue until the other day. When I use the terminal to change the mac address as I always have, I notice the wifi symbol at the top right of the kali screen disappear. However, if I click on that top bar, it still lists me as connected to my network even though the browser will not connect and ping attempts to the net result in a message: Network is unreachable. I can shut off the wifi and then reconnect, however, this resets my mac address also. The router does not have mac filtering enabled, so it should not do this and it never has until now. I tested the same machine on a different network and it had the same behavior, so I was not able to isolate the issue to the network. I performed all update, upgrade, dist-upgrade, linux-headers, and verified my source list, and the problem persists. Next I tried a different computer running Kali Rolling also. It had not been fully updated. I performed the macchange without any of these problems. Great. Then I ran the update, upgrade, dist-upgrade, linux-headers, and verified my source list. Now this machine is behaving like the other one. One of the machines is on virtual box (mac) and the other is on a dual boot pc. I have also attempted using two different usb wireless interfaces that have been verified to work for a while, however the result is the same. When using the virtual box edition and the virtual wired connection to piggyback off of OSX'swireless connection, I am able to take that interface down and up without issue. It has nothing to do with macchanger though. I tested it out simply taking the interface down and then up again ifconfig wlan0 down ifconfig wlan0 up Same result. The interface does not come back up and ping attempts to the net result in: connect: Network is unreachable Taking the interface down and switching to monitor mode works fine, even with a macchange as well. No problems. Taking the interface back down and switching to managed mode is where it fails upon bringing the interface back up. The ifconfig wlan0 up command does not revive the interface in managed mode. Here is what ifconfig wlan0 pulls up. The first result is from when the interface is not responding to the ifconfig wlan0 up command. The second result is from after resetting the wifi so it is connected again. Notice the only difference I believe is the inet6 line. wlan0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 172.16.42.8 netmask 255.255.255.0 broadcast 172.16.42.255 ether d6:a5:43:22:b9:f8 txqueuelen 1000 (Ethernet) RX packets 315 bytes 49230 (48.0 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 45 bytes 5778 (5.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 root@kali:~# ifconfig wlan0 wlan0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 172.16.42.8 netmask 255.255.255.0 broadcast 172.16.42.255 inet6 fe80::758e:4b7d:e880:d1f5 prefixlen 64 scopeid 0x20<link> ether d6:a5:43:22:b9:f8 txqueuelen 1000 (Ethernet) RX packets 322 bytes 50216 (49.0 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 60 bytes 7506 (7.3 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
Additional Information	Makes macchanging and several other features unusable when needing to take down the interface and bring it back up in managed more. Also renders many custom scripts what include the interface down/up commands unusable as well.
Attached Files	Screen Shot 2016-05-30 at 1.30.02 PM.jpg (607,936 bytes)

dner 2016-05-29 02:34 reporter ~0005293	Although wlan0 will not connect after ifconfig wlan0 up, it seems that attempting to run macchanger -r after that command will result in the error message you would expect if you attempt macchanger -r while the interface is up. So even though there is no internet connection and the wifi signal does not return to the top right of the screen, the OS does think the interface is up.

dner 2016-05-30 07:12 reporter ~0005295	Tonight I downloaded a fresh ISO from kali.org and installed via virtual box. Right out of the gate I had this exact same issue.

dner 2016-05-30 20:39 reporter ~0005300	Screenshot just added. This shows a working ping to 8.8.8.8 followed by iwconfig result. Then ifconfig wlan0 down followed by ifconfig wlan0 up. Now the same ping attempt returns a Network unreachable result, after which I pull the result of another ifconfig. Notice, however in the top right of the screen, it shows that I am in fact connected to the network. To further verify that the interface is up, I test it by attempting a macchanger -r wlan0 command, which yields the error message: Could not change MAC: interface up or insufficient permissions: Device or resource busy So the interface is up and it is connected to the network. Even the DNS servers match those of the host machine which is connected to the internet. But the network comes back unreachable, regardless.

dner 2016-05-30 23:46 reporter ~0005301	UPDATE: I have been working at isolating the issue and I think I have figured out where it is. Everything is fine until I: ifconfig wlan0 down ifconfig wlan0 up The network shows connected still if you bring down the network list at the top right of the screen, however, ping attempts to the net result in: Network unreachable. HOWEVER, ping attempts on the local network work just fine. Temporary fix (example of a macchange): ifconfig wlan0 down macchanger -r wlan0 ifconfig wlan0 up route add default gw 192.168.1.254 macchanger -s wlan0 (verifies that the spoofed mac address is currently active) So the issue is in the 4th line where I need to manually add the default gateway: route add default gw {current gateway ip} Of course if you are mobile and connect to multiple networks, then scripting things like macchanges or anything else that requires a interface down/up sequence is really a problem as I would need to enter it manually. The question is, why would I now need to manually input the gateway ip to achieve this when I never had to perform such a task before?

rhertzog 2016-05-31 06:57 administrator ~0005302	If you cut the network connection, then you have to reconfigure it the next time you bring it up. That's nothing new really. Maybe you were using DHCP before? In any case it's not a bug.

Date Modified	Username	Field	Change
2016-05-28 18:43	dner	New Issue
2016-05-29 02:34	dner	Note Added: 0005293
2016-05-30 07:12	dner	Note Added: 0005295
2016-05-30 20:31	dner	File Added: Screen Shot 2016-05-30 at 1.30.02 PM.jpg
2016-05-30 20:39	dner	Note Added: 0005300
2016-05-30 23:46	dner	Note Added: 0005301
2016-05-31 06:57	rhertzog	Note Added: 0005302
2016-05-31 06:57	rhertzog	Status	new => closed
2016-05-31 06:57	rhertzog	Assigned To	=> rhertzog
2016-05-31 06:57	rhertzog	Resolution	open => no change required
2025-07-14 09:36	g0tmi1k	Priority	high => normal