| 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-2022-49291: ALSA: pcm: Fix races among concurrent hw_params and hw_free calls |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| ALSA: pcm: Fix races among concurrent hw_params and hw_free calls |
| |
| Currently we have neither proper check nor protection against the |
| concurrent calls of PCM hw_params and hw_free ioctls, which may result |
| in a UAF. Since the existing PCM stream lock can't be used for |
| protecting the whole ioctl operations, we need a new mutex to protect |
| those racy calls. |
| |
| This patch introduced a new mutex, runtime->buffer_mutex, and applies |
| it to both hw_params and hw_free ioctl code paths. Along with it, the |
| both functions are slightly modified (the mmap_count check is moved |
| into the state-check block) for code simplicity. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49291 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 4.14.279 with commit a42aa926843acca96c0dfbde2e835b8137f2f092 |
| Fixed in 4.19.243 with commit 9cb6c40a6ebe4a0cfc9d6a181958211682cffea9 |
| Fixed in 5.4.193 with commit fbeb492694ce0441053de57699e1e2b7bc148a69 |
| Fixed in 5.10.109 with commit 0f6947f5f5208f6ebd4d76a82a4757e2839a23f8 |
| Fixed in 5.15.32 with commit 33061d0fba51d2bf70a2ef9645f703c33fe8e438 |
| Fixed in 5.16.18 with commit 0090c13cbbdffd7da079ac56f80373a9a1be0bf8 |
| Fixed in 5.17.1 with commit 1bbf82d9f961414d6c76a08f7f843ea068e0ab7b |
| Fixed in 5.18 with commit 92ee3c60ec9fe64404dc035e7c41277d74aa26cb |
| |
| 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-2022-49291 |
| 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: |
| include/sound/pcm.h |
| sound/core/pcm.c |
| sound/core/pcm_native.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/a42aa926843acca96c0dfbde2e835b8137f2f092 |
| https://git.kernel.org/stable/c/9cb6c40a6ebe4a0cfc9d6a181958211682cffea9 |
| https://git.kernel.org/stable/c/fbeb492694ce0441053de57699e1e2b7bc148a69 |
| https://git.kernel.org/stable/c/0f6947f5f5208f6ebd4d76a82a4757e2839a23f8 |
| https://git.kernel.org/stable/c/33061d0fba51d2bf70a2ef9645f703c33fe8e438 |
| https://git.kernel.org/stable/c/0090c13cbbdffd7da079ac56f80373a9a1be0bf8 |
| https://git.kernel.org/stable/c/1bbf82d9f961414d6c76a08f7f843ea068e0ab7b |
| https://git.kernel.org/stable/c/92ee3c60ec9fe64404dc035e7c41277d74aa26cb |
