{"api_version":"1","generated_at":"2026-10-24T20:21:00+00:00","cve":"CVE-2026-93227","urls":{"html":"https://cve.report/CVE-2026-93227","api":"https://cve.report/api/cve/CVE-2026-93227.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-93227","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-93227"},"summary":{"title":"mm/mm_init: deferred_grow_zone(): fix out-of-range first_deferred_pfn","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mm_init: deferred_grow_zone(): fix out-of-range first_deferred_pfn\n\nWith CONFIG_DEFERRED_STRUCT_PAGE_INIT enabled, deferred_grow_zone()\ninitializes struct pages early in boot to satisfy an allocation.\n\nWith a large CMA reservation in place, the ranges deferred_init_memmap()\nfinds may not add up to the allocation it was asked for, and the function\nends up initializing the memory map of the entire zone and still falls\nshort.\n\nThat is fine in itself: the function accounts for it and leaves the\ncaller to decide whether it now has enough memory.\n\nHowever, the update of pgdat->first_deferred_pfn that tracks where\nuninitialized memory map starts could overflow.\n\nIf the node's RAM end is not aligned on PAGES_PER_SECTION boundaries and\nsome deferred struct pages were initialized, pgdat->first_deferred_pfn\nwould point past the end of the node's memory.\n\ndeferred_init_memmap() later picks up from pgdat->first_deferred_pfn and\nhits a BUG_ON(), because it expects a pfn within its node.\n\nFor example, when running a kernel with CONFIG_DEFERRED_STRUCT_PAGE_INIT=y\nand CONFIG_CMA=y using the following qemu command line\n\n  qemu-system-x86_64 -enable-kvm -m 8032M -kernel bzImage \\\n      -append \"nokaslr cma=4768M@0x100000000\"\n\nthe kernel panics:\n\n  kernel BUG at mm/mm_init.c:2131!\n  CPU: 3 UID: 0 PID: 36 Comm: pgdatinit0 Not tainted 7.2.0-rc6 #1\n  RIP: 0010:deferred_init_memmap+0x1b8/0x1c0\n  RAX: 0000000000236000 R13: 0000000000238000\n  Call Trace:\n   kthread+0xdf/0x120\n   ret_from_fork+0x187/0x250\n\nMake sure that the update of pgdta->first_deferred_pfn does not overflow\nwhen the entire zone's (and therefore node's) memory map is initialized.\n\n[rppt: massaged the changelog]","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-24 16:17:18","updated_at":"2026-10-19 10:17:13"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/97090500d776c3f6d08e857e3a0a7cf092999094","name":"https://git.kernel.org/stable/c/97090500d776c3f6d08e857e3a0a7cf092999094","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/45489d4f95802903ab35799b400b346fa4e13151","name":"https://git.kernel.org/stable/c/45489d4f95802903ab35799b400b346fa4e13151","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/84339578c2d6936ac3a93cd1f0bbaa3468a988f2","name":"https://git.kernel.org/stable/c/84339578c2d6936ac3a93cd1f0bbaa3468a988f2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-93227","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93227","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3acb913c9d5bd8dcf61677ccba96d349e7681cf8 45489d4f95802903ab35799b400b346fa4e13151 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3acb913c9d5bd8dcf61677ccba96d349e7681cf8 84339578c2d6936ac3a93cd1f0bbaa3468a988f2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3acb913c9d5bd8dcf61677ccba96d349e7681cf8 97090500d776c3f6d08e857e3a0a7cf092999094 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.18","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.50 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.4 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["mm/mm_init.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"45489d4f95802903ab35799b400b346fa4e13151","status":"affected","version":"3acb913c9d5bd8dcf61677ccba96d349e7681cf8","versionType":"git"},{"lessThan":"84339578c2d6936ac3a93cd1f0bbaa3468a988f2","status":"affected","version":"3acb913c9d5bd8dcf61677ccba96d349e7681cf8","versionType":"git"},{"lessThan":"97090500d776c3f6d08e857e3a0a7cf092999094","status":"affected","version":"3acb913c9d5bd8dcf61677ccba96d349e7681cf8","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["mm/mm_init.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.18"},{"lessThan":"6.18","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.50","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.50","versionStartIncluding":"6.18","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.4","versionStartIncluding":"6.18","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"6.18","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mm_init: deferred_grow_zone(): fix out-of-range first_deferred_pfn\n\nWith CONFIG_DEFERRED_STRUCT_PAGE_INIT enabled, deferred_grow_zone()\ninitializes struct pages early in boot to satisfy an allocation.\n\nWith a large CMA reservation in place, the ranges deferred_init_memmap()\nfinds may not add up to the allocation it was asked for, and the function\nends up initializing the memory map of the entire zone and still falls\nshort.\n\nThat is fine in itself: the function accounts for it and leaves the\ncaller to decide whether it now has enough memory.\n\nHowever, the update of pgdat->first_deferred_pfn that tracks where\nuninitialized memory map starts could overflow.\n\nIf the node's RAM end is not aligned on PAGES_PER_SECTION boundaries and\nsome deferred struct pages were initialized, pgdat->first_deferred_pfn\nwould point past the end of the node's memory.\n\ndeferred_init_memmap() later picks up from pgdat->first_deferred_pfn and\nhits a BUG_ON(), because it expects a pfn within its node.\n\nFor example, when running a kernel with CONFIG_DEFERRED_STRUCT_PAGE_INIT=y\nand CONFIG_CMA=y using the following qemu command line\n\n  qemu-system-x86_64 -enable-kvm -m 8032M -kernel bzImage \\\n      -append \"nokaslr cma=4768M@0x100000000\"\n\nthe kernel panics:\n\n  kernel BUG at mm/mm_init.c:2131!\n  CPU: 3 UID: 0 PID: 36 Comm: pgdatinit0 Not tainted 7.2.0-rc6 #1\n  RIP: 0010:deferred_init_memmap+0x1b8/0x1c0\n  RAX: 0000000000236000 R13: 0000000000238000\n  Call Trace:\n   kthread+0xdf/0x120\n   ret_from_fork+0x187/0x250\n\nMake sure that the update of pgdta->first_deferred_pfn does not overflow\nwhen the entire zone's (and therefore node's) memory map is initialized.\n\n[rppt: massaged the changelog]"}],"providerMetadata":{"dateUpdated":"2026-10-19T09:07:38.667Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/45489d4f95802903ab35799b400b346fa4e13151"},{"url":"https://git.kernel.org/stable/c/84339578c2d6936ac3a93cd1f0bbaa3468a988f2"},{"url":"https://git.kernel.org/stable/c/97090500d776c3f6d08e857e3a0a7cf092999094"}],"title":"mm/mm_init: deferred_grow_zone(): fix out-of-range first_deferred_pfn","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-93227","datePublished":"2026-09-24T15:29:00.289Z","dateReserved":"2026-09-17T16:02:15.094Z","dateUpdated":"2026-10-19T09:07:38.667Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-24 16:17:18","lastModifiedDate":"2026-10-19 10:17:13","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"93227","Ordinal":"1","Title":"mm/mm_init: deferred_grow_zone(): fix out-of-range first_deferre","CVE":"CVE-2026-93227","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"93227","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mm_init: deferred_grow_zone(): fix out-of-range first_deferred_pfn\n\nWith CONFIG_DEFERRED_STRUCT_PAGE_INIT enabled, deferred_grow_zone()\ninitializes struct pages early in boot to satisfy an allocation.\n\nWith a large CMA reservation in place, the ranges deferred_init_memmap()\nfinds may not add up to the allocation it was asked for, and the function\nends up initializing the memory map of the entire zone and still falls\nshort.\n\nThat is fine in itself: the function accounts for it and leaves the\ncaller to decide whether it now has enough memory.\n\nHowever, the update of pgdat->first_deferred_pfn that tracks where\nuninitialized memory map starts could overflow.\n\nIf the node's RAM end is not aligned on PAGES_PER_SECTION boundaries and\nsome deferred struct pages were initialized, pgdat->first_deferred_pfn\nwould point past the end of the node's memory.\n\ndeferred_init_memmap() later picks up from pgdat->first_deferred_pfn and\nhits a BUG_ON(), because it expects a pfn within its node.\n\nFor example, when running a kernel with CONFIG_DEFERRED_STRUCT_PAGE_INIT=y\nand CONFIG_CMA=y using the following qemu command line\n\n  qemu-system-x86_64 -enable-kvm -m 8032M -kernel bzImage \\\n      -append \"nokaslr cma=4768M@0x100000000\"\n\nthe kernel panics:\n\n  kernel BUG at mm/mm_init.c:2131!\n  CPU: 3 UID: 0 PID: 36 Comm: pgdatinit0 Not tainted 7.2.0-rc6 #1\n  RIP: 0010:deferred_init_memmap+0x1b8/0x1c0\n  RAX: 0000000000236000 R13: 0000000000238000\n  Call Trace:\n   kthread+0xdf/0x120\n   ret_from_fork+0x187/0x250\n\nMake sure that the update of pgdta->first_deferred_pfn does not overflow\nwhen the entire zone's (and therefore node's) memory map is initialized.\n\n[rppt: massaged the changelog]","Type":"Description","Title":"mm/mm_init: deferred_grow_zone(): fix out-of-range first_deferre"}]}}}