Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: timer: Fix UAF at snd_timer_user_params() At releasing a timer object, e.g. when a userspace timer (CONFIG_SND_UTIMER) gets closed and snd_timer_free() is called, it tries to detach the timer instances and release the resources. However, it's still possible that other in-flight tasks are holding the timer instance where the to-be-deleted timer object is associated, and this may lead to racy accesses. Fortunately, most of ioctls dealing with the timer instance list already have the protection with register_mutex, and this also avoids such races. But, SNDRV_TIMER_IOCTL_PARAMS isn't protected, hence the concurrent ioctl may lead to use-after-free. This patch just adds the guard with register_mutex to protect snd_timer_user_params() for covering the code path as a quick workaround. It's no hot-path but rather a rarely issued ioctl, so the performance penalty doesn't matter.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
37745918e0e7575bc40f38da93a99b9fa6406224 to < 38034d04d4a75bbca01df2b313ced0bcd0fa3242affected37745918e0e7575bc40f38da93a99b9fa6406224 to < 3d39da65b5c422c5e5afb7d5651b0698d060a827affected37745918e0e7575bc40f38da93a99b9fa6406224 to < 306427adf9b97e29e5958cb9cf3096c6151fc9ffaffected37745918e0e7575bc40f38da93a99b9fa6406224 to < 053a401b592be424fea9d57c789f66cd5d8cec11affected
Linux Linux
Default version status: affected
6.12affected0 to < 6.12unaffected6.12.94 to ≤ 6.12.*unaffected6.18.36 to ≤ 6.18.*unaffected7.0.13 to ≤ 7.0.*unaffected7.1 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/38034d04d4a75bbca01df2b313ced0bcd0fa3242 ↗
- https://git.kernel.org/stable/c/3d39da65b5c422c5e5afb7d5651b0698d060a827 ↗
- https://git.kernel.org/stable/c/306427adf9b97e29e5958cb9cf3096c6151fc9ff ↗
- https://git.kernel.org/stable/c/053a401b592be424fea9d57c789f66cd5d8cec11 ↗
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html ↗