In the Linux kernel, the following vulnerability has been resolved: fbdev: serialize mode sysfs access with lock_fb_info() show_mode(), show_modes(), and store_mode() access fb_info->modelist and fb_info->mode without holding lock_fb_info(). store_modes() takes lock_fb_info() while replacing the modelist and freeing the old one. A concurrent reader or writer can load a pointer to an old modelist entry before store_modes() frees it, then dereference freed memory or store a stale freed pointer in fb_info->mode. Take lock_fb_info() in show_mode(), show_modes(), and store_mode() to serialize with store_modes(). In show_mode(), copy the mode to the stack and format after dropping the lock. In store_mode(), split activate() into a _locked variant to avoid double-locking, and hold the locks for the modelist walk, mode conversion, activation, and fb_info->mode assignment together.
History

Fri, 04 Sep 2026 17:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-362
CWE-416

Fri, 04 Sep 2026 15:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: fbdev: serialize mode sysfs access with lock_fb_info() show_mode(), show_modes(), and store_mode() access fb_info->modelist and fb_info->mode without holding lock_fb_info(). store_modes() takes lock_fb_info() while replacing the modelist and freeing the old one. A concurrent reader or writer can load a pointer to an old modelist entry before store_modes() frees it, then dereference freed memory or store a stale freed pointer in fb_info->mode. Take lock_fb_info() in show_mode(), show_modes(), and store_mode() to serialize with store_modes(). In show_mode(), copy the mode to the stack and format after dropping the lock. In store_mode(), split activate() into a _locked variant to avoid double-locking, and hold the locks for the modelist walk, mode conversion, activation, and fb_info->mode assignment together.
Title fbdev: serialize mode sysfs access with lock_fb_info()
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2026-09-04T15:12:57.076Z

Updated: 2026-09-07T14:21:08.600Z

Reserved: 2026-08-26T14:34:25.793Z

Link: CVE-2026-80785

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-04T16:18:04.470

Modified: 2026-09-07T15:17:32.513

Link: CVE-2026-80785

cve-icon Redhat

No data.