CVE-2026-72203
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: ntfs: skip extent mft records in writeback to prevent deadlock This patch fixes the ABBA deadlock between extent_lock and extent mrec_lock triggered by xfstests generic/113, that occurs since the commit 6994acf33bae ("ntfs: use base mft_no when looking up base inode for extent record"). Path A (inode writeback): VFS writeback -> ntfs_write_inode() -> __ntfs_write_inode() -> mutex_lock(&ni->extent_lock) -> mutex_lock(&tni->mrec_lock) Path B (MFT folio writeback): VFS writeback of $MFT dirty folios -> ntfs_mft_writepages() -> ntfs_write_mft_block() -> ntfs_may_write_mft_record() -> holds one extent mrec_lock from a previous iteration -> tries to acquire another base inode extent_lock By removing all extent_lock and extent mrec_lock acquisition from the MFT folio writeback path, the ABBA lock ordering is eliminated: Path A: __ntfs_write_inode(): extent_lock -> mrec_lock Path B (removed): ntfs_write_mft_block(): mrec_lock -> extent_lock Path B is always redundant for extent records because: 1. mark_mft_record_dirty(ext_ni) does NOT dirty the MFT folio. It only sets NInoDirty(ext_ni) and marks the base VFS inode dirty via __mark_inode_dirty(I_DIRTY_DATASYNC), which triggers Path A. Therefore, normal extent modifications never create a situation where the MFT folio is dirty and Path B is not scheduled. 2. The MFT folio only gets dirtied via ntfs_mft_mark_dirty() inside ntfs_mft_record_alloc(). But all identified callers in attrib.c (ntfs_attr_add, ntfs_attr_record_move_away, ntfs_attr_make_non_resident, ntfs_attr_record_resize) follow through with mark_mft_record_dirty(), which triggers Path A to write the complete record. 3. ntfs_evict_big_inode() calls ntfs_commit_inode() before freeing extent inodes, ensuring all dirty extents are flushed via Path A before the base inode leaves the icache.
View original CVE JSON
{
"id": "CVE-2026-72203",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-08-15T06:21:38.970",
"lastModified": "2026-10-30T13:19:48.343",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: skip extent mft records in writeback to prevent deadlock\n\nThis patch fixes the ABBA deadlock between extent_lock and extent\nmrec_lock triggered by xfstests generic/113, that occurs since the commit\n6994acf33bae (\"ntfs: use base mft_no when looking up base inode for\n\t\textent record\").\n\nPath A (inode writeback):\n VFS writeback\n -> ntfs_write_inode()\n -> __ntfs_write_inode()\n -> mutex_lock(&ni->extent_lock)\n -> mutex_lock(&tni->mrec_lock)\n\nPath B (MFT folio writeback):\n VFS writeback of $MFT dirty folios\n -> ntfs_mft_writepages()\n -> ntfs_write_mft_block()\n -> ntfs_may_write_mft_record()\n -> holds one extent mrec_lock from a previous iteration\n -> tries to acquire another base inode extent_lock\n\nBy removing all extent_lock and extent mrec_lock acquisition from the MFT\nfolio writeback path, the ABBA lock ordering is eliminated:\n\nPath A: __ntfs_write_inode(): extent_lock -> mrec_lock\nPath B (removed): ntfs_write_mft_block(): mrec_lock -> extent_lock\n\nPath B is always redundant for extent records because:\n\n1. mark_mft_record_dirty(ext_ni) does NOT dirty the MFT folio.\n It only sets NInoDirty(ext_ni) and marks the base VFS inode dirty\n via __mark_inode_dirty(I_DIRTY_DATASYNC), which triggers Path A.\n Therefore, normal extent modifications never create a situation where\n the MFT folio is dirty and Path B is not scheduled.\n\n2. The MFT folio only gets dirtied via ntfs_mft_mark_dirty() inside\n ntfs_mft_record_alloc(). But all identified callers in attrib.c\n (ntfs_attr_add, ntfs_attr_record_move_away,\n ntfs_attr_make_non_resident, ntfs_attr_record_resize) follow through\n with mark_mft_record_dirty(), which triggers Path A to write the\n complete record.\n\n3. ntfs_evict_big_inode() calls ntfs_commit_inode() before freeing extent\n inodes, ensuring all dirty extents are flushed via Path A before the\n base inode leaves the icache."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"fs/ntfs/mft.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "b06b4fc2138ded8ee0b3dc602991ff6dbb10dd0a",
"versionType": "git",
"status": "affected"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "6626fb859f4c4772f2f59751d23937716e03f98f",
"versionType": "git",
"status": "affected"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "7ffa8f3d30236e0ab897c30bdb01224ff1fe1c89",
"versionType": "git",
"status": "affected"
},
{
"version": "1e9ea7e04472d4e5e12e58c881eaacfb3e49b669",
"lessThan": "f831ab09d521898bf1dd99bf5adfd630ea1428e3",
"versionType": "git",
"status": "affected"
},
{
"version": "1e9ea7e04472d4e5e12e58c881eaacfb3e49b669",
"lessThan": "76bc14c7097ff678b2b5dbfd4fa33b46897d87ce",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"fs/ntfs/mft.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "2.6.12",
"status": "affected"
},
{
"version": "7.1",
"status": "affected"
},
{
"version": "0",
"lessThan": "2.6.12",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.191",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.160",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.9",
"lessThan": "7.1",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.1.5",
"lessThanOrEqual": "7.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 3.9,
"impactScore": 3.6
}
]
},
"references": [
{
"url": "https://git.kernel.org/stable/c/6626fb859f4c4772f2f59751d23937716e03f98f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/76bc14c7097ff678b2b5dbfd4fa33b46897d87ce",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/7ffa8f3d30236e0ab897c30bdb01224ff1fe1c89",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/b06b4fc2138ded8ee0b3dc602991ff6dbb10dd0a",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f831ab09d521898bf1dd99bf5adfd630ea1428e3",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}