| 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-2022-49733: ALSA: pcm: oss: Fix race at SNDCTL_DSP_SYNC |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| ALSA: pcm: oss: Fix race at SNDCTL_DSP_SYNC |
| |
| There is a small race window at snd_pcm_oss_sync() that is called from |
| OSS PCM SNDCTL_DSP_SYNC ioctl; namely the function calls |
| snd_pcm_oss_make_ready() at first, then takes the params_lock mutex |
| for the rest. When the stream is set up again by another thread |
| between them, it leads to inconsistency, and may result in unexpected |
| results such as NULL dereference of OSS buffer as a fuzzer spotted |
| recently. |
| |
| The fix is simply to cover snd_pcm_oss_make_ready() call into the same |
| params_lock mutex with snd_pcm_oss_make_ready_locked() variant. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49733 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 5.4.215 with commit 4051324a6dafd7053c74c475e80b3ba10ae672b0 |
| Fixed in 5.10.148 with commit fce793a056c604b41a298317cf704dae255f1b36 |
| Fixed in 5.15.68 with commit 8015ef9e8a0ee5cecfd0cb6805834d007ab26f86 |
| Fixed in 5.19.9 with commit 723ac5ab2891b6c10dd6cc78ef5456af593490eb |
| Fixed in 6.0 with commit 8423f0b6d513b259fdab9c9bf4aaa6188d054c2d |
| |
| 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-2022-49733 |
| 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/oss/pcm_oss.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/4051324a6dafd7053c74c475e80b3ba10ae672b0 |
| https://git.kernel.org/stable/c/fce793a056c604b41a298317cf704dae255f1b36 |
| https://git.kernel.org/stable/c/8015ef9e8a0ee5cecfd0cb6805834d007ab26f86 |
| https://git.kernel.org/stable/c/723ac5ab2891b6c10dd6cc78ef5456af593490eb |
| https://git.kernel.org/stable/c/8423f0b6d513b259fdab9c9bf4aaa6188d054c2d |
