{"id":"CVE-2025-40167","title":"ext4: detect invalid INLINE_DATA + EXTENTS flag combination","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: detect invalid INLINE_DATA + EXTENTS flag combination\n\nsyzbot reported a BUG_ON in ext4_es_cache_extent() when opening a verity\nfile on a corrupted ext4 filesyste…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 4954d297c91d292630ab43ba4d195dc371ce65d3","Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < f061f7c331fc16250fc82aa68964f35821687217","Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 2e9e10657b04152ed0d6ecae8d0c02a3405e28f5","Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 1437c95ab2a28b138d4521653583729f61ccb48b","Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < cb6039b68efa547b676a8a10fc4618d9d1865c23","Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < de985264eef64be8a90595908f2e6a87946dad34","Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 1f5ccd22ff482639133f2a0fe08f6d19d0e68717","Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 1d3ad183943b38eec2acf72a0ae98e635dc8456b","Linux 3.8"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-15T21:57:26.297320Z"},"published":"2025-11-12","updated":"2026-10-15","sourceUpdated":"2026-10-15T22:02:39.184Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-40167","references":[{"url":"https://git.kernel.org/stable/c/4954d297c91d292630ab43ba4d195dc371ce65d3"},{"url":"https://git.kernel.org/stable/c/f061f7c331fc16250fc82aa68964f35821687217"},{"url":"https://git.kernel.org/stable/c/2e9e10657b04152ed0d6ecae8d0c02a3405e28f5"},{"url":"https://git.kernel.org/stable/c/1437c95ab2a28b138d4521653583729f61ccb48b"},{"url":"https://git.kernel.org/stable/c/cb6039b68efa547b676a8a10fc4618d9d1865c23"},{"url":"https://git.kernel.org/stable/c/de985264eef64be8a90595908f2e6a87946dad34"},{"url":"https://git.kernel.org/stable/c/1f5ccd22ff482639133f2a0fe08f6d19d0e68717"},{"url":"https://git.kernel.org/stable/c/1d3ad183943b38eec2acf72a0ae98e635dc8456b"}],"tags":["cve.org"],"epss":0.00165,"epssPercentile":0.05404,"ingestedAt":"2026-10-15T22:48:25.548Z","slug":"CVE-2025-40167","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\next4: detect invalid INLINE_DATA + EXTENTS flag combination\n\nsyzbot reported a BUG_ON in ext4_es_cache_extent() when opening a verity\nfile on a corrupted ext4 filesystem mounted without a journal.\n\nThe issue is that the filesystem has an inode with both the INLINE_DATA\nand EXTENTS flags set:\n\n    EXT4-fs error (device loop0): ext4_cache_extents:545: inode #15:\n    comm syz.0.17: corrupted extent tree: lblk 0 < prev 66\n\nInvestigation revealed that the inode has both flags set:\n    DEBUG: inode 15 - flag=1, i_inline_off=164, has_inline=1, extents_flag=1\n\nThis is an invalid combination since an inode should have either:\n- INLINE_DATA: data stored directly in the inode\n- EXTENTS: data stored in extent-mapped blocks\n\nHaving both flags causes ext4_has_inline_data() to return true, skipping\nextent tree validation in __ext4_iget(). The unvalidated out-of-order\nextents then trigger a BUG_ON in ext4_es_cache_extent() due to integer\nunderflow when calculating hole sizes.\n\nFix this by detecting this invalid flag combination early in ext4_iget()\nand rejecting the corrupted inode.\n\n## Affected\n\n- `Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 4954d297c91d292630ab43ba4d195dc371ce65d3`\n- `Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < f061f7c331fc16250fc82aa68964f35821687217`\n- `Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 2e9e10657b04152ed0d6ecae8d0c02a3405e28f5`\n- `Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 1437c95ab2a28b138d4521653583729f61ccb48b`\n- `Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < cb6039b68efa547b676a8a10fc4618d9d1865c23`\n- `Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < de985264eef64be8a90595908f2e6a87946dad34`\n- `Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 1f5ccd22ff482639133f2a0fe08f6d19d0e68717`\n- `Linux >= f19d5870cbf72d4cb2a8e1f749dff97af99b071e < 1d3ad183943b38eec2acf72a0ae98e635dc8456b`\n- `Linux 3.8`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}