{"id":"CVE-2025-38478","summary":"comedi: Fix initialization of data for instructions that write to subdevice","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ncomedi: Fix initialization of data for instructions that write to subdevice\n\nSome Comedi subdevice instruction handlers are known to access\ninstruction data elements beyond the first `insn-\u003en` elements in some\ncases.  The `do_insn_ioctl()` and `do_insnlist_ioctl()` functions\nallocate at least `MIN_SAMPLES` (16) data elements to deal with this,\nbut they do not initialize all of that.  For Comedi instruction codes\nthat write to the subdevice, the first `insn-\u003en` data elements are\ncopied from user-space, but the remaining elements are left\nuninitialized.  That could be a problem if the subdevice instruction\nhandler reads the uninitialized data.  Ensure that the first\n`MIN_SAMPLES` elements are initialized before calling these instruction\nhandlers, filling the uncopied elements with 0.  For\n`do_insnlist_ioctl()`, the same data buffer elements are used for\nhandling a list of instructions, so ensure the first `MIN_SAMPLES`\nelements are initialized for each instruction that writes to the\nsubdevice.","modified":"2026-03-20T12:42:53.048627Z","published":"2025-07-28T11:21:44.210Z","related":["MGASA-2025-0218","MGASA-2025-0219","SUSE-SU-2025:02853-1","SUSE-SU-2025:02923-1","SUSE-SU-2025:02969-1","SUSE-SU-2025:02996-1","SUSE-SU-2025:02997-1","SUSE-SU-2025:03011-1","SUSE-SU-2025:03023-1","SUSE-SU-2025:20577-1","SUSE-SU-2025:20586-1","SUSE-SU-2025:20601-1","SUSE-SU-2025:20602-1","SUSE-SU-2025:21074-1","SUSE-SU-2025:21139-1","SUSE-SU-2025:21179-1","openSUSE-SU-2025:20081-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/38xxx/CVE-2025-38478.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/020eed5681d0f9bced73970368078a92d6cfaa9c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/13e4d9038a1e869445a996a3f604a84ef52fe8f4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/46d8c744136ce2454aa4c35c138cc06817f92b8e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/673ee92bd2d31055bca98a1d96b653f5284289c4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6f38c6380c3b38a05032b8881e41137385a6ce02"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c42116dc70af6664526f7aa82cf937824ab42649"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d3436638738ace8f101af7bdee2eae1bc38e9b29"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fe8713fb4e4e82a4f91910d9a41bf0613e69a0b9"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/38xxx/CVE-2025-38478.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-38478"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"ed9eccbe8970f6eedc1b978c157caf1251a896d4"},{"fixed":"6f38c6380c3b38a05032b8881e41137385a6ce02"},{"fixed":"13e4d9038a1e869445a996a3f604a84ef52fe8f4"},{"fixed":"020eed5681d0f9bced73970368078a92d6cfaa9c"},{"fixed":"d3436638738ace8f101af7bdee2eae1bc38e9b29"},{"fixed":"673ee92bd2d31055bca98a1d96b653f5284289c4"},{"fixed":"c42116dc70af6664526f7aa82cf937824ab42649"},{"fixed":"fe8713fb4e4e82a4f91910d9a41bf0613e69a0b9"},{"fixed":"46d8c744136ce2454aa4c35c138cc06817f92b8e"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-38478.json"}}],"schema_version":"1.7.5"}