CVE-2024-48876

In the Linux kernel, the following vulnerability has been resolved:

stackdepot: fix stack_depot_save_flags() in NMI context

Per documentation, stack_depot_save_flags() was meant to be usable from NMI context if STACK_DEPOT_FLAG_CAN_ALLOC is unset. However, it still would try to take the pool_lock in an attempt to save a stack trace in the current pool (if space is available).

This could result in deadlock if an NMI is handled while pool_lock is already held. To avoid deadlock, only try to take the lock in NMI context and give up if unsuccessful.

The documentation is fixed to clearly convey this.

Affected Software

References

• https://git.kernel.org/stable/c/031e04bdc834cda3b054ef6b698503b2b97e8186
• https://git.kernel.org/stable/c/9bfeeeff2c92b9dd261198b601b45bde4c529841