Description
In the Linux kernel, the following vulnerability has been resolved: comedi: Fix initialization of data for instructions that write to subdevice Some Comedi subdevice instruction handlers are known to access instruction data elements beyond the first `insn->n` elements in some cases. The `do_insn_ioctl()` and `do_insnlist_ioctl()` functions allocate at least `MIN_SAMPLES` (16) data elements to deal with this, but they do not initialize all of that. For Comedi instruction codes that write to the subdevice, the first `insn->n` data elements are copied from user-space, but the remaining elements are left uninitialized. That could be a problem if the subdevice instruction handler reads the uninitialized data. Ensure that the first `MIN_SAMPLES` elements are initialized before calling these instruction handlers, filling the uncopied elements with 0. For `do_insnlist_ioctl()`, the same data buffer elements are used for handling a list of instructions, so ensure the first `MIN_SAMPLES` elements are initialized for each instruction that writes to the subdevice.
Product status
ed9eccbe8970f6eedc1b978c157caf1251a896d4 (git) before 6f38c6380c3b38a05032b8881e41137385a6ce02
ed9eccbe8970f6eedc1b978c157caf1251a896d4 (git) before 13e4d9038a1e869445a996a3f604a84ef52fe8f4
ed9eccbe8970f6eedc1b978c157caf1251a896d4 (git) before 020eed5681d0f9bced73970368078a92d6cfaa9c
ed9eccbe8970f6eedc1b978c157caf1251a896d4 (git) before d3436638738ace8f101af7bdee2eae1bc38e9b29
ed9eccbe8970f6eedc1b978c157caf1251a896d4 (git) before 673ee92bd2d31055bca98a1d96b653f5284289c4
ed9eccbe8970f6eedc1b978c157caf1251a896d4 (git) before c42116dc70af6664526f7aa82cf937824ab42649
ed9eccbe8970f6eedc1b978c157caf1251a896d4 (git) before fe8713fb4e4e82a4f91910d9a41bf0613e69a0b9
ed9eccbe8970f6eedc1b978c157caf1251a896d4 (git) before 46d8c744136ce2454aa4c35c138cc06817f92b8e
2.6.29
Any version before 2.6.29
5.4.297 (semver)
5.10.241 (semver)
5.15.190 (semver)
6.1.147 (semver)
6.6.100 (semver)
6.12.40 (semver)
6.15.8 (semver)
6.16 (original_commit_for_fix)
References
lists.debian.org/debian-lts-announce/2025/10/msg00008.html
lists.debian.org/debian-lts-announce/2025/10/msg00007.html
git.kernel.org/...c/6f38c6380c3b38a05032b8881e41137385a6ce02
git.kernel.org/...c/13e4d9038a1e869445a996a3f604a84ef52fe8f4
git.kernel.org/...c/020eed5681d0f9bced73970368078a92d6cfaa9c
git.kernel.org/...c/d3436638738ace8f101af7bdee2eae1bc38e9b29
git.kernel.org/...c/673ee92bd2d31055bca98a1d96b653f5284289c4
git.kernel.org/...c/c42116dc70af6664526f7aa82cf937824ab42649
git.kernel.org/...c/fe8713fb4e4e82a4f91910d9a41bf0613e69a0b9
git.kernel.org/...c/46d8c744136ce2454aa4c35c138cc06817f92b8e