Description
In the Linux kernel, the following vulnerability has been resolved: fbdev: core: fbcvt: avoid division by 0 in fb_cvt_hperiod() In fb_find_mode_cvt(), iff mode->refresh somehow happens to be 0x80000000, cvt.f_refresh will become 0 when multiplying it by 2 due to overflow. It's then passed to fb_cvt_hperiod(), where it's used as a divider -- division by 0 will result in kernel oops. Add a sanity check for cvt.f_refresh to avoid such overflow... Found by Linux Verification Center (linuxtesting.org) with the Svace static analysis tool.
Affected products
linux: linux kernel; debian: debian linux
References10
- git.kernel.org/stable/c/2d63433e8eaa3c91b2948190e395bc67009db0d9 Patch
- git.kernel.org/stable/c/3f6dae09fc8c306eb70fdfef70726e1f154e173a Patch
- git.kernel.org/stable/c/53784073cbad18f75583fd3da9ffdfc4d1f05405 Patch
- git.kernel.org/stable/c/54947530663edcbaaee1314c01fdd8c72861b124 Patch
- git.kernel.org/stable/c/610f247f2772e4f92b63442125a1b7ade79898d8 Patch
- git.kernel.org/stable/c/9027ce4c037b566b658b8939a76326b7125e3627 Patch
- git.kernel.org/stable/c/ab91647acdf43b984824776559a452212eaeb21a Patch
- git.kernel.org/stable/c/b235393b9f43ff86a38ca2bde6372312ea215dc5 Patch
- lists.debian.org/debian-lts-announce/2025/10/msg00007.html Third Party Advisory
- lists.debian.org/debian-lts-announce/2025/10/msg00008.html Third Party Advisory
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 8 · as of 7 November 2026
- CWE
- CWE-369
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