{"schema":"threatline.record/2","record":{"id":"CVE-2026-97942","aliases":[],"summary":"x86/alternatives: Exclude text poking against change_page_attr()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/alternatives: Exclude text poking against change_page_attr()\n\nFrom time to time, the following BUG can be observed\nin the x86 alternatives patching code [0]:\n\n  > kernel BUG at arch/x86/kernel/alternative.c:2576!\n  > Oops: invalid opcode: 0000 [#1] SMP NOPTI\n  > CPU: 0 UID: 0 PID: 355 Comm: (udev-worker) Not tainted 7.1.3-1-default #1 PREEMPT(full) openSUSE Tumbleweed  8c1795b03ec64f997e57a8ad38b1161e3b98da64\n  > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS unknown 02/02/2022\n  > RIP: 0010:__text_poke+0x2aa/0x450\n  > Call Trace:\n  >  <TASK>\n  >  smp_text_poke_batch_finish+0x2a7/0x320\n  >  __static_call_transform+0xb7/0x220\n  >  arch_static_call_transform+0x5b/0xb0\n  >  __static_call_init+0xe9/0x270\n  >  static_call_module_notify+0x11f/0x150\n  >  notifier_call_chain+0x61/0xe0\n  >  blocking_notifier_call_chain_robust+0x63/0xc0\n  >  load_module+0x1c92/0x20c0\n  >  init_module_from_file+0xd8/0x140\n  >  idempotent_init_module+0x100/0x2f0\n  >  __x64_sys_finit_module+0x71/0xe0\n  >  do_syscall_64+0xe1/0x610\n  >  entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nwhich matches the following BUG_ON() in alternative.c:\n\n\t/*\n\t * If something went wrong, crash and burn since recovery paths are not\n\t * implemented.\n\t */\n\tBUG_ON(!pages[0] || (cross_page_boundary && !pages[1]));\n\nThis can happen if vmalloc_to_page() fails, for any reason. Such can happen\nif text poking races with CPA, which can possibly result in the collapsing\nof page tables (or breaking of PMD hugepages). It is not a problem for most\nusers of vmalloc_to_page() (they solely own the vmalloc'd range) but, when\nCONFIG_ARCH_HAS_EXECMEM_ROX=y, various modules own a single execmem vmalloc\nrange, and can call set_memory_*() in parallel on it. This can happen to\nrace against __text_poke and cause havoc in vmalloc_to_page().\n\nFix it by excluding against CPA using the init_mm mmap read lock.\n\n[ dhansen: Fix up SoB ordering. The actual code flow here was:\n\t   Pedro=>Lorenzo=>Mike=>Me which is reflected in the SoB chain\n\t   now. I *believe* Mike simply picked up Lorenzo's update to\n\t   Pedro's post from the Link ]","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97942","source_modified_at":"2026-10-19T09:11:08.757Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"64f6a4e10c05ed527f0f24b7954964255e0d3535","lessThan":"281e6f536f2f3f95d91938c5bd7ba9bcb4c1049d","status":"affected","versionType":"git"},{"version":"64f6a4e10c05ed527f0f24b7954964255e0d3535","lessThan":"89c60435b90d32ab5e3a39da3ae73d463d07debe","status":"affected","versionType":"git"},{"version":"64f6a4e10c05ed527f0f24b7954964255e0d3535","lessThan":"1587d3394e254639cc36516256031334095e6ef3","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97942","source_modified_at":"2026-10-19T09:11:08.757Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"6.15","status":"affected"},{"version":"0","lessThan":"6.15","status":"unaffected","versionType":"semver"},{"version":"6.18.53","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.7","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97942","source_modified_at":"2026-10-19T09:11:08.757Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"281e6f536f2f3f95d91938c5bd7ba9bcb4c1049d","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97942","source_modified_at":"2026-10-19T09:11:08.757Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"89c60435b90d32ab5e3a39da3ae73d463d07debe","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97942","source_modified_at":"2026-10-19T09:11:08.757Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"1587d3394e254639cc36516256031334095e6ef3","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.00198,"percentile":0.0905,"score_date":"2026-10-23"},"published_at":"2026-09-25T10:22:54.188Z","modified_at":"2026-10-19T09:11:08.757Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-97942","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T09:11:08.757Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-97942","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/281e6f536f2f3f95d91938c5bd7ba9bcb4c1049d"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/89c60435b90d32ab5e3a39da3ae73d463d07debe"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/1587d3394e254639cc36516256031334095e6ef3"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-19T09:11:08.757Z","content_hash":"34edb62d8af7fd4d7d182f10cf5e9105571a2ba32bf21cc33ac51662fc67a66d"}}