| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2023-52503: tee: amdtee: fix use-after-free vulnerability in amdtee_close_session |
| |
| 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. |
| |
| The Linux kernel CVE team has assigned CVE-2023-52503 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.6 with commit 757cc3e9ff1d72d014096399d6e2bf03974d9da1 and fixed in 5.10.199 with commit da7ce52a2f6c468946195b116615297d3d113a27 |
| Issue introduced in 5.6 with commit 757cc3e9ff1d72d014096399d6e2bf03974d9da1 and fixed in 5.15.136 with commit 1680c82929bc14d706065f123dab77f2f1293116 |
| Issue introduced in 5.6 with commit 757cc3e9ff1d72d014096399d6e2bf03974d9da1 and fixed in 6.1.59 with commit 60c3e7a00db954947c265b55099c21b216f2a05c |
| Issue introduced in 5.6 with commit 757cc3e9ff1d72d014096399d6e2bf03974d9da1 and fixed in 6.5.8 with commit 1c95574350cd63bc3c5c2fa06658010768f2a0ce |
| Issue introduced in 5.6 with commit 757cc3e9ff1d72d014096399d6e2bf03974d9da1 and fixed in 6.6 with commit f4384b3e54ea813868bb81a861bf5b2406e15d8f |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2023-52503 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| drivers/tee/amdtee/core.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| 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 |
