Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
can: j1939: make j1939_session_activate() fail if device is no longer registered
syzbot is still reporting
unregister_netdevice: waiting for vcan0 to become free. Usage count = 2
even after commit 93a27b5891b8 (“can: j1939: add missing calls in NETDEV_UNREGISTER notification handler”) was added. A debug printk() patch found that j1939_session_activate() can succeed even after j1939_cancel_active_session() from j1939_netdev_notify(NETDEV_UNREGISTER) has completed.
Since j1939_cancel_active_session() is processed with the session list lock held, checking ndev->reg_state in j1939_session_activate() with the session list lock held can reliably close the race window.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , Ubuntu 20.04 ELS
- Affected packages:
- kernel @ 5.14.0 (+4 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| AlmaLinux 9.2 ESU | Planned | — |
| AlmaLinux 9.6 ESU | Planned | — |
| Debian 11 | Will Not Fix | — |
| Debian 11 cloud | Will Not Fix | — |
| Debian 12 | Planned | — |
| Debian 13 | Planned | — |
| Oracle Linux 8 UEK 7 | In Progress | — |
| Oracle Linux 9 UEK 7 | In Progress | — |
| Ubuntu 22.04 | Planned | — |
| Ubuntu 22.04 AWS | Planned | — |
| Ubuntu 24.04 | Released |
43 kernels
|
| Ubuntu 24.04 AWS | Planned | — |