{"id":"CVE-2026-98223","state":"PUBLISHED","title":"mm: filemap: retain mapped dropbehind folios","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm: filemap: retain mapped dropbehind folios\n\nFault-around can map ready dropbehind folios without going through the\nnormal page-cache lookup that clears dropbehind.  A mapping represents a\ncompeting cached user, so retain the folio instead of forcibly unmapping\nit when writeback completes.\n\nFor a mapped folio, folio_unmap_invalidate() can call\nunmap_mapping_folio(), which takes i_mmap_rwsem and may sleep.  Retaining\nmapped folios avoids this path when folio_end_dropbehind() runs in\nnon-preemptible task context.\n\nTal was able to trigger a sleeping-in-atomic warning due to this [1].\n\nUnmapped dropbehind folios continue through the existing invalidation path.","publishedAt":"2026-10-06T08:44:58.472Z","updatedAt":"2026-10-19T09:15:55.143Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"fb7d3bc4149395c1ae99029c852eab6c28fc3c88","status":"affected","lessThan":"2897601dffe576fcd87a4259102f41f7fb0cbfc8","versionType":"git"},{"version":"fb7d3bc4149395c1ae99029c852eab6c28fc3c88","status":"affected","lessThan":"77c0fade37c80e8aa16ac048a9828249055e3f66","versionType":"git"},{"version":"fb7d3bc4149395c1ae99029c852eab6c28fc3c88","status":"affected","lessThan":"848d2ce2fce15fbdc083fbf9691bfa72911033c4","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["mm/filemap.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.14","versionType":"semver"},{"version":"6.18.54","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.8","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":["mm/filemap.c"]}],"references":["https://git.kernel.org/stable/c/2897601dffe576fcd87a4259102f41f7fb0cbfc8","https://git.kernel.org/stable/c/77c0fade37c80e8aa16ac048a9828249055e3f66","https://git.kernel.org/stable/c/848d2ce2fce15fbdc083fbf9691bfa72911033c4"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98223.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98223","state":"PUBLISHED","datePublished":"2026-10-06T08:44:58.472Z","dateUpdated":"2026-10-19T09:15:55.143Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.327Z"},"containers":{"cna":{"title":"mm: filemap: retain mapped dropbehind folios","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm: filemap: retain mapped dropbehind folios\n\nFault-around can map ready dropbehind folios without going through the\nnormal page-cache lookup that clears dropbehind.  A mapping represents a\ncompeting cached user, so retain the folio instead of forcibly unmapping\nit when writeback completes.\n\nFor a mapped folio, folio_unmap_invalidate() can call\nunmap_mapping_folio(), which takes i_mmap_rwsem and may sleep.  Retaining\nmapped folios avoids this path when folio_end_dropbehind() runs in\nnon-preemptible task context.\n\nTal was able to trigger a sleeping-in-atomic warning due to this [1].\n\nUnmapped dropbehind folios continue through the existing invalidation path."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"fb7d3bc4149395c1ae99029c852eab6c28fc3c88","status":"affected","lessThan":"2897601dffe576fcd87a4259102f41f7fb0cbfc8","versionType":"git"},{"version":"fb7d3bc4149395c1ae99029c852eab6c28fc3c88","status":"affected","lessThan":"77c0fade37c80e8aa16ac048a9828249055e3f66","versionType":"git"},{"version":"fb7d3bc4149395c1ae99029c852eab6c28fc3c88","status":"affected","lessThan":"848d2ce2fce15fbdc083fbf9691bfa72911033c4","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["mm/filemap.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.14","versionType":"semver"},{"version":"6.18.54","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.8","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":["mm/filemap.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/2897601dffe576fcd87a4259102f41f7fb0cbfc8"},{"url":"https://git.kernel.org/stable/c/77c0fade37c80e8aa16ac048a9828249055e3f66"},{"url":"https://git.kernel.org/stable/c/848d2ce2fce15fbdc083fbf9691bfa72911033c4"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:15:55.143Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14","versionEndExcluding":"6.18.54"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14","versionEndExcluding":"7.2.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}