Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
can: esd_usb: kill anchored URBs before freeing netdevs
esd_usb_disconnect() frees each CAN netdev with free_candev() inside its per-netdev loop and only calls unlink_all_urbs(dev) afterwards. The per-netdev private data (struct esd_usb_net_priv) is embedded in the net_device allocation returned by alloc_candev(), so once free_candev() has run, dev->nets[i] points to freed memory. unlink_all_urbs() then dereferences the freed dev->nets[i] to kill the per-netdev TX anchor (usb_kill_anchored_urbs(&priv->tx_submitted)), clear active_tx_jobs, and reset priv->tx_contexts[].
Reorder the teardown so the anchored URBs are killed before the netdevs are freed, matching other CAN/USB drivers in the same directory such as ems_usb, usb_8dev and mcba_usb, which unregister, then unlink, then free: unregister the netdevs first (which stops their TX queues), call unlink_all_urbs(dev) once, then free the netdevs.
This issue was found by an in-house static analysis tool.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 5.10.259 (+17 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 12 | Released |
42 kernels
|
| Debian 13 | Released |
13 kernels
|
| Oracle Linux 8 UEK 7 | Planned | — |
| Oracle Linux 9 UEK 7 | Planned | — |
| Ubuntu 24.04 | Planned | — |
| Ubuntu 24.04 AWS | Planned | — |
| Ubuntu 26.04 | Will Not Fix | — |