ext4: convert inline data to extents when truncate exceeds inline size (Linux Linux)

CVE-2026-31452
HIGH 7.8

At a glance

Source
NVD
EPSS
EPSS 0.14 % · percentile 3 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Modified

Description

In the Linux kernel, the following vulnerability has been resolved: ext4: convert inline data to extents when truncate exceeds inline size Add a check in ext4_setattr() to convert files from inline data storage to extent-based storage when truncate() grows the file size beyond the inline capacity. This prevents the filesystem from entering an inconsistent state where the inline data flag is set but the file size exceeds what can be stored inline. Without this fix, the following sequence causes a kernel BUG_ON(): 1. Mount filesystem with inode that has inline flag set and small size 2. truncate(file, 50MB) - grows size but inline flag remains set 3. sendfile() attempts to write data 4. ext4_write_inline_data() hits BUG_ON(write_size > inline_capacity) The crash occurs because ext4_write_inline_data() expects inline storage to accommodate the write, but the actual inline capacity (~60 bytes for i_block + ~96 bytes for xattrs) is far smaller than the file size and write request. The fix checks if the new size from setattr exceeds the inode's actual inline capacity (EXT4_I(inode)->i_inline_size) and converts the file to extent-based storage before proceeding with the size change. This addresses the root cause by ensuring the inline data flag and file size remain consistent during truncate operations.

Weaknesses (CWE)

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD · nvd@nist.gov (Primary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected 67cf5b09a46f72e048501b84996f2f77bc42e947 < 110d7ef602659ce4d7947c5480f7ca2779696aaf ; affected 67cf5b09a46f72e048501b84996f2f77bc42e947 < f53a5d9f32924bc2a810d2df243b7714da58b636 ; affected 67cf5b09a46f72e048501b84996f2f77bc42e947 < c047332be7195833a5c5126816c2502df8269fe4 ; affected 67cf5b09a46f72e048501b84996f2f77bc42e947 < 699bac4d4c951974d55b045c983d1de777215949 ; affected 67cf5b09a46f72e048501b84996f2f77bc42e947 < 7920dcc571cef3d8aa9ee109c136125d61d41669 ; affected 67cf5b09a46f72e048501b84996f2f77bc42e947 < 93cb2d103e5c707de0f7ad58a39b7f0fddc27aa6
Linux · Linuxaffected 3.8 ; unaffected 0 < 3.8 ; unaffected 5.10.253 ≤ 5.10.* ; unaffected 5.15.203 ≤ 5.15.* ; unaffected 6.1.168 ≤ 6.1.* ; unaffected 6.6.131 ≤ 6.6.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD