drm/gem: Fix inconsistent plane dimension calculation in drm_gem_fb_init_with_funcs()

MITRE NVD CVE.ORG JSON API Print: PDF PDF

Summary

CVECVE-2026-46209
StatePUBLISHED
AssignerLinux
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-05-28 10:16:36 UTC
Updated2026-05-28 10:16:36 UTC
DescriptionIn the Linux kernel, the following vulnerability has been resolved: drm/gem: Fix inconsistent plane dimension calculation in drm_gem_fb_init_with_funcs() drm_gem_fb_init_with_funcs() computes sub-sampled plane dimensions using plain integer division: unsigned int width = mode_cmd->width / (i ? info->hsub : 1); unsigned int height = mode_cmd->height / (i ? info->vsub : 1); However, the ioctl-level framebuffer_check() in drm_framebuffer.c uses drm_format_info_plane_width/height() which round up dimensions via DIV_ROUND_UP(). This inconsistency corrupts the subsequent GEM object size check for certain pixel format and dimension combinations. For example, with NV12 (vsub=2) and a 1-pixel-tall framebuffer the GEM size validation path sees height=0 instead of height=1. The expression (height - 1) then wraps to UINT_MAX as an unsigned int, causing min_size to overflow and wrap back to a small value. A tiny GEM object therefore passes the size guard, yet when the GPU accesses the chroma plane it will read or write memory beyond the object's bounds. Fix by replacing the open-coded divisions with drm_format_info_plane_width() and drm_format_info_plane_height(), which use DIV_ROUND_UP() and match the calculation already used in framebuffer_check().

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Linux Linux affected 4c3dbb2c312c9fafbac30d98c523b8b1f3455d78 6b992591e04f2cce813bcf239b354f375bbf84d3 git Not specified
CNA Linux Linux affected 4c3dbb2c312c9fafbac30d98c523b8b1f3455d78 1da4ab7189f1064b3b712b388772c008b4d82580 git Not specified
CNA Linux Linux affected 4c3dbb2c312c9fafbac30d98c523b8b1f3455d78 1a17ea9861e89585361caa8bc231bd22dc6dbe7d git Not specified
CNA Linux Linux affected 4c3dbb2c312c9fafbac30d98c523b8b1f3455d78 c5fc49d8470c5ebf3b41607600f277158f159950 git Not specified
CNA Linux Linux affected 4c3dbb2c312c9fafbac30d98c523b8b1f3455d78 3d4c2268bd7243c3780fe32bf24ff876da272acf git Not specified
CNA Linux Linux affected 4.14 Not specified
CNA Linux Linux unaffected 4.14 semver Not specified
CNA Linux Linux unaffected 6.6.140 6.6.* semver Not specified
CNA Linux Linux unaffected 6.12.90 6.12.* semver Not specified
CNA Linux Linux unaffected 6.18.32 6.18.* semver Not specified
CNA Linux Linux unaffected 7.0.9 7.0.* semver Not specified
CNA Linux Linux unaffected 7.1-rc2 * original_commit_for_fix Not specified

References

ReferenceSourceLinkTags
git.kernel.org/stable/c/1da4ab7189f1064b3b712b388772c008b4d82580 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/c5fc49d8470c5ebf3b41607600f277158f159950 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/6b992591e04f2cce813bcf239b354f375bbf84d3 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/3d4c2268bd7243c3780fe32bf24ff876da272acf 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/1a17ea9861e89585361caa8bc231bd22dc6dbe7d 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
© CVE.report 2026 |

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report