{"schema":"threatline.record/2","record":{"id":"CVE-2026-93237","aliases":[],"summary":"LoongArch: Add DIRECT_MAP_PHYSMEM_END definition","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nLoongArch: Add DIRECT_MAP_PHYSMEM_END definition\n\nget_free_mem_region() and mhp_get_pluggable_range() bound their search\nto DIRECT_MAP_PHYSMEM_END. LoongArch does not define it, so the fallback\nin include/linux/mm.h applies: under CONFIG_SPARSEMEM_VMEMMAP it is\n(1ULL << MAX_PHYSMEM_BITS) - 1, a compile-time constant that does not\nadapt to the CPU's physical address space bits (cpu_pabits, probed from\nCPUCFG1).\n\nThe vmemmap window only covers physical space below 2^(cpu_pabits+1)\n(i.e. VMEMMAP_SIZE), so on CPUs with fewer physical address bits than\nMAX_PHYSMEM_BITS the fallback allows get_free_mem_region() to return\na ZONE_DEVICE region outside the vmemmap window; vmemmap_populate() then\nwraps the memmap range around and maps it into low memory, silently\ncorrupting the page tables. The same search also picked the top-of-\naddress-space region that crashed memmap_init_zone_device() with amdkfd\non Loongson-3C6000 in 6.16 [1]; the commit 2969b42c8f99 (\"LoongArch/mm:\nalign vmemmap to maximal folio size\") keeps that region in bounds on\ncurrent Loongson-3C6000 configs, but CPUs with smaller cpu_pabits (e.g.\nthe Loongson-2K series) are still affected.\n\nDefine DIRECT_MAP_PHYSMEM_END as the vmemmap-covered physical range,\n(1ULL << (cpu_pabits + 1)) - 1, capped at (1ULL << MAX_PHYSMEM_BITS) - 1\nunder CONFIG_SPARSEMEM, similar to the commit f3336b48cf9d (\"riscv: mm:\nDefine DIRECT_MAP_PHYSMEM_END\").\n\n[1] https://lore.kernel.org/amd-gfx/20250814032153.227285-1-jeffbai@aosc.io/","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-93237","source_modified_at":"2026-10-19T09:07:48.863Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"7b09f5af01ede480cbe7abcb281cf17550a46ff5","lessThan":"ab275a23b4d9f04ca6c2f5f6a3246194e045a761","status":"affected","versionType":"git"},{"version":"7b09f5af01ede480cbe7abcb281cf17550a46ff5","lessThan":"55e18311c705cceef6c34d522ea387b1f0069bab","status":"affected","versionType":"git"},{"version":"7b09f5af01ede480cbe7abcb281cf17550a46ff5","lessThan":"2677f97a67fdbc62a82ce1faa67791f54451d36f","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-93237","source_modified_at":"2026-10-19T09:07:48.863Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"6.2","status":"affected"},{"version":"0","lessThan":"6.2","status":"unaffected","versionType":"semver"},{"version":"6.18.51","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.5","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-2026-93237","source_modified_at":"2026-10-19T09:07:48.863Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"55e18311c705cceef6c34d522ea387b1f0069bab","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-93237","source_modified_at":"2026-10-19T09:07:48.863Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"2677f97a67fdbc62a82ce1faa67791f54451d36f","basis":"first unaffected version stated in the CVE record"}],"cvss":7.8,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00173,"percentile":0.06436,"score_date":"2026-10-23"},"published_at":"2026-09-24T15:33:51.702Z","modified_at":"2026-10-19T09:07:48.863Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-93237","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T09:07:48.863Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-93237","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/ab275a23b4d9f04ca6c2f5f6a3246194e045a761"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/55e18311c705cceef6c34d522ea387b1f0069bab"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/2677f97a67fdbc62a82ce1faa67791f54451d36f"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-19T09:07:48.863Z","content_hash":"53388319154d0beec3f2fd6eba4f8a0212928d018c30c30cbd00abb231798fc7"}}