CVE-2023-52629

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux9f5e8eee5cfe1328660c71812d87c2a67bda389f < 610dbd8ac271aa36080aac50b928d700ee3fe4deaffected
LinuxLinux9f5e8eee5cfe1328660c71812d87c2a67bda389f < 246f80a0b17f8f582b2c0996db02998239057c65affected
LinuxLinux2.6.20affected
LinuxLinux0 < 2.6.20unaffected
LinuxLinux6.5.4 <= 6.5.*unaffected
LinuxLinux6.6 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

CVE Program Container

Additional References

References