REDHAT-BUG-2382581: Medium severity Linux Foundation Linux Kernel vulnerability
In the Linux kernel, the following vulnerability has been resolved:
posix-cpu-timers: fix race between handleposixcputimers() and posixcputimerdel()
If an exiting non-autoreaping task has already passed exitnotify() and calls handleposixcputimers() from IRQ, it can be reaped by its parent or debugger right after unlocktasksighand().
If a concurrent posixcputimerdel() runs at that moment, it won't be able to detect timer->it.cpu.firing != 0: cputimertaskrcu() and/or locktasksighand() will fail.
Add the tsk->exitstate check into runposixcputimers() to fix this.
This fix is not needed if CONFIGPOSIXCPUTIMERSTASKWORK=y, because exittaskwork() is called before exitnotify(). But the check still makes sense, taskworkadd(&tsk->posixcputimerswork.work) will fail anyway in this case.
Affected Software
Event History
Frequently Asked Questions
What is the severity of REDHAT-BUG-2382581?
The severity of REDHAT-BUG-2382581 is categorized as important due to the potential for race conditions in the Linux kernel.
How do I fix REDHAT-BUG-2382581?
To fix REDHAT-BUG-2382581, update your Linux kernel to the latest version that includes the relevant patches.
What are the potential impacts of REDHAT-BUG-2382581?
The potential impacts of REDHAT-BUG-2382581 include unexpected behaviors or crashes in applications relying on CPU timers.
Which systems are affected by REDHAT-BUG-2382581?
REHAT-BUG-2382581 affects systems running the vulnerable versions of the Linux kernel.
Is there a workaround for REDHAT-BUG-2382581?
There is no formal workaround for REDHAT-BUG-2382581; applying the kernel update is the recommended solution.