In the Linux kernel, the following vulnerability has been resolved:

s390/cio: Fix device lifecycle handling in css_alloc_subchannel()

css_alloc_subchannel() calls device_initialize() before setting up
the DMA masks. If dma_set_coherent_mask() or dma_set_mask() fails,
the error path frees the subchannel structure directly, bypassing
the device model reference counting.

Once device_initialize() has been called, the embedded struct device
must be released via put_device(), allowing the release callback to
free the container structure.

Fix the error path by dropping the initial device reference with
put_device() instead of calling kfree() directly.

This ensures correct device lifetime handling and avoids potential
use-after-free or double-free issues.

References

• https://nvd.nist.gov/vuln/detail/CVE-2026-45981
• https://git.kernel.org/stable/c/2b2ad7ad4a28ffdb9f94e6d979b88a5b12b71681
• https://git.kernel.org/stable/c/6715560527e343a387e4a0d2e6c401748e89fa55
• https://git.kernel.org/stable/c/abb6e07f46a740cda4f07d1b561ae4eaa7a1df42
• https://git.kernel.org/stable/c/b1d4e6fb241672850296956c4d782a69363a3807
• https://git.kernel.org/stable/c/c35cfbb5341ba05ad1b4476ffc3c21cc3ff8f603
• https://git.kernel.org/stable/c/f65c75b0b9b5a390bc3beadcde0a6fbc3ad118f7
• https://git.kernel.org/stable/c/f96c5ccf95ae5f27218c1ce2d6a3ad2d3e105424
• https://git.kernel.org/stable/c/fd295a75d828c11acfcc6869c2a12cdaaf9b7722