CVE-2023-52503 Information

Description

In the Linux kernel the following vulnerability has been resolved:

tee: amdtee: fix use-after-free vulnerability in amdtee_close_session

There is a potential race condition in amdtee_close_session that may cause use-after-free in amdtee_open_session. For instance if a session has refcount == 1 and one thread tries to free this session via:

kref_put(&sess->refcount destroy_session);

the reference count will get decremented and the next step would be to call destroy_session(). However if in another thread amdtee_open_session() is called before destroy_session() has completed execution alloc_session() may return ‘sess’ that will be freed up later in destroy_session() leading to use-after-free in amdtee_open_session.

To fix this issue treat decrement of sess->refcount and removal of ‘sess’ from session list in destroy_session() as a critical section so that it is executed atomically.

Reference

https://git.kernel.org/stable/c/da7ce52a2f6c468946195b116615297d3d113a27 https://git.kernel.org/stable/c/1680c82929bc14d706065f123dab77f2f1293116 https://git.kernel.org/stable/c/60c3e7a00db954947c265b55099c21b216f2a05c https://git.kernel.org/stable/c/1c95574350cd63bc3c5c2fa06658010768f2a0ce https://git.kernel.org/stable/c/f4384b3e54ea813868bb81a861bf5b2406e15d8f