Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
can: isotp: fix tx.buf use-after-free in isotp_sendmsg()
isotp_sendmsg() uses only cmpxchg() on so->tx.state to serialize access to so->tx.buf. isotp_release() waits for ISOTP_IDLE via wait_event_interruptible() and then calls kfree(so->tx.buf).
If a signal interrupts the wait_event_interruptible() inside close() while tx.state is ISOTP_SENDING, the loop exits early and release proceeds to force ISOTP_SHUTDOWN and continues to kfree(so->tx.buf) while sendmsg may still be reading so->tx.buf for the final CAN frame in isotp_fill_dataframe().
The so->tx.buf can be allocated once when the standard tx.buf length needs to be extended. Move the kfree() of this potentially extended tx.buf to sk_destruct time when either isotp_sendmsg() and isotp_release() are done.
Details
- Affected product:
- AlmaLinux 9.2 ESU , TuxCare 9.6 ESU
- Affected packages:
- kernel @ 5.14.0 (+1 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| AlmaLinux 10 | Released |
44 kernels
|
| AlmaLinux 9 | Released |
31 kernels
|
| Debian 13 | Planned | — |
| Oracle Linux 10 | Released |
36 kernels
|
| Oracle Linux 9 | Released |
24 kernels
|
| RHEL 10 | Released |
43 kernels
|
| RHEL 9 | Released |
29 kernels
|
| Rocky Linux 10 | Released |
30 kernels
|
| Rocky Linux 9 | Released |
21 kernels
|
| Ubuntu 24.04 | Will Not Fix |
46 kernels
|