Revert "mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again" (Linux Linux)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.26 % · percentile 17 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Modified
Description
In the Linux kernel, the following vulnerability has been resolved: Revert "mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again" Patch series "mm: Avoid possible overflows in dirty throttling". Dirty throttling logic assumes dirty limits in page units fit into 32-bits. This patch series makes sure this is true (see patch 2/2 for more details). This patch (of 2): This reverts commit 9319b647902cbd5cc884ac08a8a6d54ce111fc78. The commit is broken in several ways. Firstly, the removed (u64) cast from the multiplication will introduce a multiplication overflow on 32-bit archs if wb_thresh * bg_thresh >= 1<<32 (which is actually common - the default settings with 4GB of RAM will trigger this). Secondly, the div64_u64() is unnecessarily expensive on 32-bit archs. We have div64_ul() in case we want to be safe & cheap. Thirdly, if dirty thresholds are larger than 1<<32 pages, then dirty balancing is going to blow up in many other spectacular ways anyway so trying to fix one possible overflow is just moot.
Weaknesses (CWE)
- CWE-369 — Divide By Zero
References
- https://git.kernel.org/stable/c/253f9ea7e8e53a5176bd80ceb174907b10724c1a
- https://git.kernel.org/stable/c/23a28f5f3f6ca1e4184bd0e9631cd0944cf1c807
- https://git.kernel.org/stable/c/145faa3d03688cbb7bbaaecbd84c01539852942c
- https://git.kernel.org/stable/c/2820005edae13b140f2d54267d1bd6bb23915f59
- https://git.kernel.org/stable/c/cbbe17a324437c0ff99881a3ee453da45b228a00
- https://git.kernel.org/stable/c/f6620df12cb6bdcad671d269debbb23573502f9d
- https://git.kernel.org/stable/c/000099d71648504fb9c7a4616f92c2b70c3e44ec
- https://git.kernel.org/stable/c/30139c702048f1097342a31302cbd3d478f50c63
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2024-39934
- GCVE · GCVE-0-2024-42102
CERT-FR advisories
- CERTFR-2025-AVI-0018 — Multiples vulnérabilités dans les produits Juniper Networks · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0002 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2024-AVI-1102 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2024-AVI-1080 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2024-AVI-1013 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0997 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0957 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0838 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0823 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0799 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0778 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0777 — Multiples vulnérabilités dans le noyau Linux de Red Hat · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0749 — Multiples vulnérabilités dans le noyau Linux de Red Hat · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0719 — Multiples vulnérabilités dans le noyau Linux de Debian · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 4.19.307 < 4.19.318cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.4.269 < 5.4.280cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.10.210 < 5.10.222cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.15.149 < 5.15.163cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.1.79 < 6.1.98cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.6.18 < 6.6.39cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.8 < 6.9.9
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected c593d26fb5d577ef31b6e49a31e08ae3ebc1bc1e < 253f9ea7e8e53a5176bd80ceb174907b10724c1a ; affected 1f12e4b3284d6c863f272eb2de0d4248ed211cf4 < 23a28f5f3f6ca1e4184bd0e9631cd0944cf1c807 ; affected 81e7d2530d458548b90a5c5e76b77ad5e5d1c0df < 145faa3d03688cbb7bbaaecbd84c01539852942c ; affected 5099871b370335809c0fd1abad74d9c7c205d43f < 2820005edae13b140f2d54267d1bd6bb23915f59 ; affected 16b1025eaa8fc223ab4273ece20d1c3a4211a95d < cbbe17a324437c0ff99881a3ee453da45b228a00 ; affected ec18ec230301583395576915d274b407743d8f6c < f6620df12cb6bdcad671d269debbb23573502f9d |
| Linux · Linux | affected 6.8 ; unaffected 0 < 6.8 ; unaffected 4.19.318 ≤ 4.19.* ; unaffected 5.4.280 ≤ 5.4.* ; unaffected 5.10.222 ≤ 5.10.* ; unaffected 5.15.163 ≤ 5.15.* |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |