Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
ALSA: us122l: Use snd_card_free_when_closed() at disconnection
The USB disconnect callback is supposed to be short and not too-long waiting. OTOH, the current code uses snd_card_free() at disconnection, but this waits for the close of all used fds, hence it can take long. It eventually blocks the upper layer USB ioctls, which may trigger a soft lockup.
An easy workaround is to replace snd_card_free() with snd_card_free_when_closed(). This variant returns immediately while the release of resources is done asynchronously by the card device release at the last close.
The loop of us122l->mmap_count check is dropped as well. The check is useless for the asynchronous operation with *_when_closed().
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 6 ELS , CloudLinux 7 ELS , Debian 10 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 4.4.0 (+18 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| AlmaLinux 9.2 ESU | Planned | — |
| Debian 11 | Planned | — |
| Debian 11 cloud | Planned | — |
| Debian 12 | Planned | — |
| Oracle Linux 7 UEK 6 | Released |
112 kernels
|
| Oracle Linux 8 UEK 6 | Released |
116 kernels
|
| Oracle Linux 8 UEK 7 | Released |
53 kernels
|
| Oracle Linux 9 UEK 7 | Released |
53 kernels
|
| Ubuntu 18.04 AWS Focal | Will Not Fix | — |
| Ubuntu 20.04 | Ready For Release | — |
| Ubuntu 22.04 | Planned | — |
| Ubuntu 22.04 AWS | Planned | — |
| Ubuntu 22.04 Azure | Planned | — |
| Ubuntu 24.04 | Released |
20 kernels
|
| Ubuntu 24.04 AWS | Ready For Release | — |