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I want to disable the internal webcam of my laptop running Ubuntu 13.10? As suggested here, I already disabled the concerning kernel modules by blacklisting them. But after reboot the modules are loaded nevertheless. What can I do to get rid of these modules?

My module blacklist lies in /etc/modprobe.d/blacklist-webcam.conf and looks like this:

blacklist videodev
blacklist videobuf2_core
blacklist videobuf2_memops
blacklist videobuf2_vmalloc
blacklist uvcvideo

But lsmod gives me (after reboot):

Module                  Size  Used by
uvcvideo               80885  0 
videobuf2_vmalloc      13216  1 uvcvideo
videobuf2_memops       13362  1 videobuf2_vmalloc
videobuf2_core         40499  1 uvcvideo
videodev              133509  2 uvcvideo,videobuf2_core

Edit:
When I do a sudo modprobe -r uvcvideo the modules are gone. So I could write a script to do that. But I would not consider that as a clean solution ;-)

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Marc Hauptmann
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  • What do you get when you type sudo modprobe -r uvcvideo? – jobin May 05 '14 at 14:14
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    Where did you saved your blacklist file? – Braiam May 05 '14 at 14:20
  • @Braiam: the blacklist lies in /etc/modprobe.d. It also contains entries to blacklist bluetooth modules. That works, so the file is interpreted. – Marc Hauptmann May 05 '14 at 17:57
  • What is the driver behind your requirement to disable the camera? Seriously, not trying to troll. If you want to free up resources used by the kmodules and whatnot, awesome. If you want the camera to not capture images/video, and don't care about a couple of kb or memory, maybe this is what you need? http://pbs.twimg.com/media/BTWPnR_CYAA2pfM.jpg get them here https://www.eff.org/deeplinks/2013/04/how-protect-against-laptop-webcam-hacking – 0xSheepdog May 05 '14 at 18:12
  • I think they are getting enabled later by udev rules. I'm not sure how you can disable those. – Braiam May 05 '14 at 18:21
  • @Sneetsher, I added the location of my blacklist to the question – Marc Hauptmann May 10 '14 at 15:01
  • @Sneetsher, everything is fine. I just figured out, why the module was loaded. Thanks for your help! – Marc Hauptmann May 10 '14 at 17:28

5 Answers5

7
  • In your blacklist.conf change blacklist videodev to install videodev /bin/false
  • update-initramfs -u
  • reboot

For more details see Kernel Modules Blacklisting on the Arch Wiki:

Blacklisting

Blacklisting, in the context of kernel modules, is a mechanism to prevent the kernel module from loading. This could be useful if, for example, the associated hardware is not needed, or if loading that module causes problems: for instance there may be two kernel modules that try to control the same piece of hardware, and loading them together would result in a conflict.

Some modules are loaded as part of the initramfs. mkinitcpio -M will print out all automatically detected modules: to prevent the initramfs from loading some of those modules, blacklist them in /etc/modprobe.d/modprobe.conf. Running mkinitcpio -v will list all modules pulled in by the various hooks (e.g. filesystems hook, block hook, etc.). Remember to add that .conf file to the FILES section in /etc/mkinitcpio.conf, if you have not done so already, and rebuild the initramfs once you have blacklisted the modules, and reboot afterwards.

Using files in /etc/modprobe.d/

Create a .conf file inside /etc/modprobe.d/ and append a line for each module you want to blacklist, using the blacklist keyword. If for example you want to prevent the pcspkr module from loading:

/etc/modprobe.d/nobeep.conf

# Do not load the 'pcspkr' module on boot.
blacklist pcspkr

Note: The blacklist command will blacklist a module so that it will not be loaded automatically, but the module may be loaded if another non-blacklisted module depends on it or if it is loaded manually.

However, there is a workaround for this behaviour; the install command instructs modprobe to run a custom command instead of inserting the module in the kernel as normal, so you can force the module to always fail loading with:

/etc/modprobe.d/blacklist.conf

...
install module_name /bin/false
...

This will effectively blacklist that module and any other that depends on it.

bain
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Just putting the list of modules in /etc/modprobe.d/blacklist.uvcdrver.conf should work. The file name can be anything. Just make sure the format and permissions are correct.

askb
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Thank you all very much for your help! I found the source of the problem while trying bain's solution. His solution works well. After reboot the modules were really gone. But there is one drawback: I can not load the module via modprobe uvcvideo in case I want to re-enable the webcam.

While digging through my system in order to find out, why the uvcvideo module was loaded, I finally made a grep -r uvcvideo /etc/ and voilà, I found a script in /etc/pm/power.d which did a modprobe uvcvideo when the power cable is plugged in. I wrote this script some time ago to optimize the power consumption. I commented out the lines dealing with the webcam module and after that, the blacklist worked!

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Marc Hauptmann
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0

I would suggest you run 

sudo update-initramfs -u

after modifying your blacklist. This will update your initial ramdisk.

fossfreedom
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N8tron
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In the case that you were after a solution in one command line instruction this might be helpful (based on this answer):

To disable the camera until reboot use this command:

sudo modprobe -r uvcvideo

Type your password and if there are no errors shown in the terminal, your webcam should be disabled. If you got the error message: modprobe: FATAL: Module uvcvideo is in use, you can try to force its removal with:

sudo rmmod -f uvcvideo

To enable your webcam back again, type in shell:

sudo modprobe uvcvideo
gaboroncancio
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