CVE-2026-74449 (GCVE-0-2026-74449)
Vulnerability from cvelistv5
Published
2026-08-15 12:26
Modified
2026-10-21 12:45
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix divide-by-zero in calculate_mcache_setting on zero viewport If a plane reaches calculate_mcache_setting with a zero-area viewport, calculate_mcache_setting exits early with num_mcaches == 0 and mvmpg_width/height == 0. This will cause a divide-by-zero panic and can also cause an underflow on num_mcaches. Fix this by changing calculate_mcache_setting to bool and adding guards after each calculate_mcache_row_bytes call. If num_mcaches or mvmpg_width/height is zero, return a false. Callers will propagate the failure as a rejected mode, which prevents the panic. (cherry picked from commit 29c0f7c655f47bcbd575ff75e58480df6ec3c9da)
References
Impacted products
Vendor Product Version
Linux Linux Version: 70839da6360500a82e4d5f78499284474cbed7c1
Version: 70839da6360500a82e4d5f78499284474cbed7c1
Version: 70839da6360500a82e4d5f78499284474cbed7c1
Version: 70839da6360500a82e4d5f78499284474cbed7c1
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