CVE-2026-53126

Description

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: fix disk reference leak in blkcg_maybe_throttle_current() Add the missing put_disk() on the error path in blkcg_maybe_throttle_current(). When blkcg lookup, blkg lookup, or blkg_tryget() fails, the function jumps to the out label which only calls rcu_read_unlock() but does not release the disk reference acquired by blkcg_schedule_throttle() via get_device(). Since current->throttle_disk is already set to NULL before the lookup, blkcg_exit() cannot release this reference either, causing the disk to never be freed. Restore the reference release that was present as blk_put_queue() in the original code but was inadvertently dropped during the conversion from request_queue to gendisk.

References

• https://git.kernel.org/stable/c/000e8454692cab9d1f1b80130e2870e355301d06
• https://git.kernel.org/stable/c/23308af722fefed00af5f238024c11710938fba3
• https://git.kernel.org/stable/c/4048ed98860d3785645ebbd34f69566a6c7320c3
• https://git.kernel.org/stable/c/73a5af059905d171b398c8b2381632ee499948b5
• https://git.kernel.org/stable/c/b3e005f16cd98f815429a87aef4c61e9c140779f