CVE-2022-49549 Information

Description

In the Linux kernel the following vulnerability has been resolved:

x86/MCE/AMD: Fix memory leak when threshold_create_bank() fails

In mce_threshold_create_device() if threshold_create_bank() fails the previously allocated threshold banks array @bp will be leaked because the call to mce_threshold_remove_device() will not free it.

This happens because mce_threshold_remove_device() fetches the pointer through the threshold_banks per-CPU variable but bp is written there only after the bank creation is successful and not before when threshold_create_bank() fails.

Add a helper which unwinds all the bank creation work previously done and pass into it the previously allocated threshold banks array for freeing.

[ bp: Massage. ]

Reference

https://git.kernel.org/stable/c/396b8e7ab2a99ddac57d3522b3da5e58cb608d37 https://git.kernel.org/stable/c/9708f1956eeb70c86943e0bc62fa3b0101b59616 https://git.kernel.org/stable/c/b4acb8e7f1594607bc9017ef0aacb40b24a003d6 https://git.kernel.org/stable/c/cc0dd4456f9573bf8af9b4d8754433918e809e1e https://git.kernel.org/stable/c/e5f28623ceb103e13fc3d7bd45edf9818b227fd0