Affected: Alpaquita:23: linux-lts, Alpaquita:25: linux-lts, Alpaquita:stream: linux-lts

In the Linux kernel, the following vulnerability has been resolved:

media: vivid: check for vb2_is_busy() when toggling caps

The vivid_update_format_cap/out() functions must only be called if the capture/output queue are not busy. But for the controls that select the CROP/COMPOSE/SCALE capability that is not checked.

Only when streaming starts will they be set to 'grabbed' and it is impossible to change the control, but between REQBUFS and STREAMON you are still allowed to set these controls. Since vivid_update_format_cap/out will change the format, this can cause unexpected results.

Besides adding these checks, also add a WARN_ON in vivid_update_format_cap/out() if the queue is busy.

I'm 90% certain that this is the cause of this syzbot bug:

https://syzkaller.appspot.com/bug?extid=dac8f5eaa46837e97b89

But since we never have reproducers, it is hard to be certain. In any case, these checks are needed regardless.

In the Linux kernel, the following vulnerability has been resolved:

media: vivid: check for vb2_is_busy() when toggling caps

The vivid_update_format_cap/out() functions must only be called if the capture/output queue are not busy. But for the controls that select the CROP/COMPOSE/SCALE capability that is not checked.

Only when streaming starts will they be set to 'grabbed' and it is impossible to change the control, but between REQBUFS and STREAMON you are still allowed to set these controls. Since vivid_update_format_cap/out will change the format, this can cause unexpected results.

Besides adding these checks, also add a WARN_ON in vivid_update_format_cap/out() if the queue is busy.

I'm 90% certain that this is the cause of this syzbot bug:

https://syzkaller.appspot.com/bug?extid=dac8f5eaa46837e97b89

But since we never have reproducers, it is hard to be certain. In any case, these checks are needed regardless.

Security update for the Linux Kernel

Security update for the Linux Kernel

Affected: Ubuntu:Pro:14.04:LTS: linux-aws, Ubuntu:Pro:14.04:LTS: linux-azure, Ubuntu:Pro:14.04:LTS: linux-lts-xenial, Ubuntu:Pro:16.04:LTS: linux, Ubuntu:Pro:16.04:LTS: linux-aws, Ubuntu:Pro:16.04:LTS: linux-aws-hwe, Ubuntu:Pro:16.04:LTS: linux-azure, Ubuntu:Pro:16.04:LTS: linux-gcp, Ubuntu:Pro:16.04:LTS: linux-hwe, Ubuntu:16.04:LTS: linux-hwe-edge and 245 more

In the Linux kernel, the following vulnerability has been resolved: media: vivid: check for vb2_is_busy() when toggling caps The vivid_update_format_cap/out() functions must only be called if the capture/output queue are not busy. But for the controls that select the CROP/COMPOSE/SCALE capability that is not checked. Only when streaming starts will they be set to 'grabbed' and it is impossible to change the control, but between REQBUFS and STREAMON you are still allowed to set these controls. Since vivid_update_format_cap/out will change the format, this can cause unexpected results. Besides adding these checks, also add a WARN_ON in vivid_update_format_cap/out() if the queue is busy. I'm 90% certain that this is the cause of this syzbot bug: https://syzkaller.appspot.com/bug?extid=dac8f5eaa46837e97b89 But since we never have reproducers, it is hard to be certain. In any case, these checks are needed regardless.

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, darunter möglicherweise die Ausführung von beliebigem Code, die Ausweitung von Berechtigungen, die Offenlegung von Informationen, die Manipulation von Daten oder Denial-of-Service-Zustände.