CVE-2023-52584

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

spmi: mediatek: Fix UAF on device remove

The pmif driver data that contains the clocks is allocated along with spmi_controller. On device remove, spmi_controller will be freed first, and then devres , including the clocks, will be cleanup. This leads to UAF because putting the clocks will access the clocks in the pmif driver data, which is already freed along with spmi_controller.

This can be reproduced by enabling DEBUG_TEST_DRIVER_REMOVE and building the kernel with KASAN.

Fix the UAF issue by using unmanaged clk_bulk_get() and putting the clocks before freeing spmi_controller.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/521f28eedd6b14228c46e3b81e3bf9b90c2818d8
• https://git.kernel.org/stable/c/9a3881b1f07db1bb55cb0108e6f05cfd027eaf2e
• https://git.kernel.org/stable/c/e821d50ab5b956ed0effa49faaf29912fd4106d9
• https://git.kernel.org/stable/c/f8dcafcb54632536684336161da8bdd52120f95e
• https://git.kernel.org/stable/c/521f28eedd6b14228c46e3b81e3bf9b90c2818d8
• https://git.kernel.org/stable/c/9a3881b1f07db1bb55cb0108e6f05cfd027eaf2e
• https://git.kernel.org/stable/c/e821d50ab5b956ed0effa49faaf29912fd4106d9
• https://git.kernel.org/stable/c/f8dcafcb54632536684336161da8bdd52120f95e