CVSS 9.8 · Critical EPSS 0,72%
Kerentanan pada linux kernel. Skor CVSS 3.1 9.8 (Critical) menurut CNA.
In the Linux kernel, the following vulnerability has been resolved: ext4: handle wraparound when searching for blocks for indirect mapped blocks Commit 4865c768b563 ("ext4: always allocate blocks only from groups inode can use") restricts what blocks will be allocated for indirect block based files to block numbers that fit within 32-bit block numbers. However, when using a review bot running on the latest Gemini LLM to check this commit when backporting into an LTS based kernel, it raised this concern: If ac->ac_g_ex.fe_group is >= ngroups (for instance, if the goal group was populated via stream allocation from s_mb_last_groups), then start will be >= ngroups. Does this allow allocating blocks beyond the 32-bit limit for indirect block mapped files? The commit message mentions that ext4_mb_scan_groups_linear() takes care to not select unsupported groups. However, its loop uses group = *start, and the very first iteration will call ext4_mb_scan_group() with this unsupported group because next_linear_group() is only called at the end of the iteration. After reviewing the code paths involved and considering the LLM review, I determined that this can happen when there is a file system where some files/directories are extent-mapped and others are indirect-block mapped. To address this, add a safety clamp in ext4_mb_scan_groups().
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| linux | linux kernel | Versi 5.15.203 hingga sebelum 5.16 |
| linux | linux kernel | Versi 6.6.130 hingga sebelum 6.6.134 |
| linux | linux kernel | Versi 6.12.77 hingga sebelum 6.12.80 |
| linux | linux kernel | Versi 6.18.14 hingga sebelum 6.18.21 |
| linux | linux kernel | Versi 6.19.4 hingga sebelum 6.19.11 |
| linux | linux kernel | Versi 6.1.167 |