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.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
Debian | 12 | all | linux | <= 6.1.76-1 | linux_6.1.76-1_all.deb |
Debian | 11 | all | linux | <= 5.10.209-2 | linux_5.10.209-2_all.deb |
Debian | 10 | all | linux | <= 4.19.249-2 | linux_4.19.249-2_all.deb |
Debian | 999 | all | linux | < 6.5.6-1 | linux_6.5.6-1_all.deb |
Debian | 13 | all | linux | < 6.5.6-1 | linux_6.5.6-1_all.deb |