Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
ieee802154: ca8210: fix cas_ctl leak on spi_async failure
ca8210_spi_transfer() allocates cas_ctl with kzalloc_obj(GFP_ATOMIC) and relies entirely on the SPI completion callback ca8210_spi_transfer_complete() to free it.
The spi_async() API only invokes the completion callback on successful submission. On failure it returns a negative error code without ever queuing the callback, which leaves cas_ctl and its embedded spi_message and spi_transfer orphaned. Every kfree(cas_ctl) in the driver is inside the completion callback, so there is no other reclamation path.
ca8210_spi_transfer() is called from ca8210_spi_exchange(), the interrupt handler ca8210_interrupt_handler(), and from the retry path inside the completion callback itself. The exchange and interrupt handler paths loop on -EBUSY, so under sustained SPI bus contention every retry iteration leaks a fresh cas_ctl (~600 bytes per occurrence).
Fix it by freeing cas_ctl on the spi_async() error path. While here, correct the misleading error string: the function calls spi_async(), not spi_sync().
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 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 @ 4.19.0 (+12 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 12 | Will Not Fix |
42 kernels
|
| Debian 13 | Will Not Fix |
13 kernels
|
| Ubuntu 22.04 | Planned | — |
| Ubuntu 22.04 AWS | Planned | — |
| Ubuntu 22.04 Azure | Planned | — |
| Ubuntu 24.04 | Planned | — |
| Ubuntu 24.04 AWS | Planned | — |
| Ubuntu 26.04 | In Rollout |
2 kernels
|