CVE-2026-100073 — ext4: fix transaction overflow during writeback
In the Linux kernel, the following vulnerability has been resolved: ext4: fix transaction overflow during writeback Commit 95ad8ee45cdb ("ext4: correct the reserved credits fo…
Published: 2026-09-25 · CVSS: Unscored
In the Linux kernel, the following vulnerability has been resolved: ext4: fix transaction overflow during writeback Commit 95ad8ee45cdb ("ext4: correct the reserved credits for extent conversion") was correct to note that we need to reserve enough credits for all extents possibly underlying a large folio. However it was too eager to reduce the number of reserved credits. Extent conversion may not only need to touch several leaf extent blocks, it may also need to split extents - for example a single large unwritten extent may need to be split into many small written ones in case of sparse folio dirtying. This can thus result not only in extent leaf modifications but also in a need to allocate new extent tree nodes. As a result the reserved transaction credits were not sufficient in some corner cases. Use ext4_meta_trans_blocks() for correct upper bound credit estimate.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7