CVE-2023-52629 — In the Linux kernel, the following vulnerability has been resolved: sh: push-switch: Reorder cleanup…
Linux · Linux Kernel · Published 29 Mar 2024 · Modified 3 Oct 2026
Description
In the Linux kernel, the following vulnerability has been resolved: sh: push-switch: Reorder cleanup operations to avoid use-after-free bug The original code puts flush_work() before timer_shutdown_sync() in switch_drv_remove(). Although we use flush_work() to stop the worker, it could be rescheduled in switch_timer(). As a result, a use-after-free bug can occur. The details are shown below: (cpu 0) | (cpu 1) switch_drv_remove() | flush_work() | ... | switch_timer // timer | schedule_work(&psw->work) timer_shutdown_sync() | ... | switch_work_handler // worker kfree(psw) // free | | psw->state = 0 // use This patch puts timer_shutdown_sync() before flush_work() to mitigate the bugs. As a result, the worker and timer will be stopped safely before the deallocate operations.
References
- https://git.kernel.org/stable/c/246f80a0b17f8f582b2c0996db02998239057c65
- https://git.kernel.org/stable/c/610dbd8ac271aa36080aac50b928d700ee3fe4de
- https://git.kernel.org/stable/c/ff635d1f143b55fa005e9e43b16e6d8f677e90a5
- https://git.kernel.org/stable/c/246f80a0b17f8f582b2c0996db02998239057c65
- https://git.kernel.org/stable/c/610dbd8ac271aa36080aac50b928d700ee3fe4de
- Check whether Linux Kernel is in your asset inventory.
- Patch in the next maintenance window; prioritise internet-facing systems.
- Record the decision in your risk register for audit evidence.
Link: adminadda.com/cve/CVE-2023-52629