| From bippy-1.2.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2025-23134: ALSA: timer: Don't take register_mutex with copy_from/to_user() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| ALSA: timer: Don't take register_mutex with copy_from/to_user() |
| |
| The infamous mmap_lock taken in copy_from/to_user() can be often |
| problematic when it's called inside another mutex, as they might lead |
| to deadlocks. |
| |
| In the case of ALSA timer code, the bad pattern is with |
| guard(mutex)(®ister_mutex) that covers copy_from/to_user() -- which |
| was mistakenly introduced at converting to guard(), and it had been |
| carefully worked around in the past. |
| |
| This patch fixes those pieces simply by moving copy_from/to_user() out |
| of the register mutex lock again. |
| |
| The Linux kernel CVE team has assigned CVE-2025-23134 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.9 with commit 3923de04c81733b30b8ed667569632272fdfed9a and fixed in 6.12.23 with commit 15291b561d8cc835a2eea76b394070cf8e072771 |
| Issue introduced in 6.9 with commit 3923de04c81733b30b8ed667569632272fdfed9a and fixed in 6.13.11 with commit 296f7a9e15aab276db11206cbc1e2ae1215d7862 |
| Issue introduced in 6.9 with commit 3923de04c81733b30b8ed667569632272fdfed9a and fixed in 6.14.2 with commit b074f47e55df93832bbbca1b524c501e6fea1c0d |
| Issue introduced in 6.9 with commit 3923de04c81733b30b8ed667569632272fdfed9a and fixed in 6.15 with commit 3424c8f53bc63c87712a7fc22dc13d0cc85fb0d6 |
| |
| 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-2025-23134 |
| 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: |
| sound/core/timer.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/15291b561d8cc835a2eea76b394070cf8e072771 |
| https://git.kernel.org/stable/c/296f7a9e15aab276db11206cbc1e2ae1215d7862 |
| https://git.kernel.org/stable/c/b074f47e55df93832bbbca1b524c501e6fea1c0d |
| https://git.kernel.org/stable/c/3424c8f53bc63c87712a7fc22dc13d0cc85fb0d6 |
