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.
Metrics
Affected Vendors & Products
References
History
Mon, 10 Aug 2026 14:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-668 CWE-754 |
Mon, 10 Aug 2026 12:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Title | media: vivid: check for vb2_is_busy() when toggling caps | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-08-10T12:00:23.311Z
Reserved: 2026-07-30T09:28:09.374Z
Link: CVE-2026-68204
No data.
No data.
No data.
OpenCVE Enrichment
Updated: 2026-08-10T18:15:11Z