CVE-2025-21836 Information

Description

In the Linux kernel the following vulnerability has been resolved:

io_uring/kbuf: reallocate buf lists on upgrade

IORING_REGISTER_PBUF_RING can reuse an old struct io_buffer_list if it was created for legacy selected buffer and has been emptied. It violates the requirement that most of the field should stay stable after publish. Always reallocate it instead.

Reference

https://git.kernel.org/stable/c/146a185f6c05ee263db715f860620606303c4633 https://git.kernel.org/stable/c/2a5febbef40ce968e295a7aeaa5d5cbd9e3e5ad4 https://git.kernel.org/stable/c/7d0dc28dae836caf7645fef62a10befc624dd17b https://git.kernel.org/stable/c/8802766324e1f5d414a81ac43365c20142e85603