{"id":"CVE-2026-98390","state":"PUBLISHED","title":"x86/amd_node: Avoid divide by zero on virtualized systems","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/amd_node: Avoid divide by zero on virtualized systems\n\nOn a virtualized system, the number of nodes does not have a relationship to\nthe number of roots.  A Xen PVH dom0 can calculate roots_per_node as 0, which\ncrashes with a divide by zero in:\n\n  if (count++ % roots_per_node)\n\nbecause the underlying topology code on Xen ends up making num_nodes\n2 and num_roots 1 and the integer division result is 0.\n\nThe issue is seen with Xen, but it could affect other systems.\n\nSet roots_per_node to 1 in this case. Print a firmware bug when this is\nperformed for non-virtualized systems.\n\n  [ bp: Massage commit message. ]","publishedAt":"2026-10-14T13:25:54.905Z","updatedAt":"2026-10-19T09:18:41.175Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0a4b61d9c2e496b5f0a10e29e355a1465c8738bb","status":"affected","lessThan":"9273a90465d58b82aca4bea71451ef6bee084928","versionType":"git"},{"version":"0a4b61d9c2e496b5f0a10e29e355a1465c8738bb","status":"affected","lessThan":"94e984d8858a3228952b02f84e66610961098cc2","versionType":"git"},{"version":"0a4b61d9c2e496b5f0a10e29e355a1465c8738bb","status":"affected","lessThan":"72bd92bd8190d7869ecb462649ca40f297822a33","versionType":"git"},{"version":"c4ad899a33198ab6335732c769835d035e66894a","status":"affected","versionType":"git"},{"version":"6.17.8","status":"affected","lessThan":"6.18","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kernel/amd_node.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kernel/amd_node.c"]}],"references":["https://git.kernel.org/stable/c/9273a90465d58b82aca4bea71451ef6bee084928","https://git.kernel.org/stable/c/94e984d8858a3228952b02f84e66610961098cc2","https://git.kernel.org/stable/c/72bd92bd8190d7869ecb462649ca40f297822a33"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98390.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98390","state":"PUBLISHED","datePublished":"2026-10-14T13:25:54.905Z","dateUpdated":"2026-10-19T09:18:41.175Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.346Z"},"containers":{"cna":{"title":"x86/amd_node: Avoid divide by zero on virtualized systems","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/amd_node: Avoid divide by zero on virtualized systems\n\nOn a virtualized system, the number of nodes does not have a relationship to\nthe number of roots.  A Xen PVH dom0 can calculate roots_per_node as 0, which\ncrashes with a divide by zero in:\n\n  if (count++ % roots_per_node)\n\nbecause the underlying topology code on Xen ends up making num_nodes\n2 and num_roots 1 and the integer division result is 0.\n\nThe issue is seen with Xen, but it could affect other systems.\n\nSet roots_per_node to 1 in this case. Print a firmware bug when this is\nperformed for non-virtualized systems.\n\n  [ bp: Massage commit message. ]"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0a4b61d9c2e496b5f0a10e29e355a1465c8738bb","status":"affected","lessThan":"9273a90465d58b82aca4bea71451ef6bee084928","versionType":"git"},{"version":"0a4b61d9c2e496b5f0a10e29e355a1465c8738bb","status":"affected","lessThan":"94e984d8858a3228952b02f84e66610961098cc2","versionType":"git"},{"version":"0a4b61d9c2e496b5f0a10e29e355a1465c8738bb","status":"affected","lessThan":"72bd92bd8190d7869ecb462649ca40f297822a33","versionType":"git"},{"version":"c4ad899a33198ab6335732c769835d035e66894a","status":"affected","versionType":"git"},{"version":"6.17.8","status":"affected","lessThan":"6.18","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kernel/amd_node.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kernel/amd_node.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/9273a90465d58b82aca4bea71451ef6bee084928"},{"url":"https://git.kernel.org/stable/c/94e984d8858a3228952b02f84e66610961098cc2"},{"url":"https://git.kernel.org/stable/c/72bd92bd8190d7869ecb462649ca40f297822a33"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:18:41.175Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"6.18.53"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"7.2.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"7.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17.8"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}