CVE-2025-68296
- Source
- https://cve.org/CVERecord?id=CVE-2025-68296
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-68296.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2025-68296
- Downstream
- Related
- Published
- 2025-12-16T15:06:15Z
- Modified
- 2026-08-12T03:30:37Z
- Summary
- drm, fbcon, vga_switcheroo: Avoid race condition in fbcon setup
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
drm, fbcon, vga_switcheroo: Avoid race condition in fbcon setup
Protect vga_switcheroo_client_fb_set() with console lock. Avoids OOB access in fbcon_remap_all(). Without holding the console lock the call races with switching outputs.
VGA switcheroo calls fbcon_remap_all() when switching clients. The fbcon function uses struct fb_info.node, which is set by register_framebuffer(). As the fb-helper code currently sets up VGA switcheroo before registering the framebuffer, the value of node is -1 and therefore not a legal value. For example, fbcon uses the value within set_con2fb_map() [1] as an index into an array.
Moving vga_switcheroo_client_fb_set() after register_framebuffer() can result in VGA switching that does not switch fbcon correctly.
Therefore move vga_switcheroo_client_fb_set() under fbcon_fb_registered(), which already holds the console lock. Fbdev calls fbcon_fb_registered() from within register_framebuffer(). Serializes the helper with VGA switcheroo's call to fbcon_remap_all().
Although vga_switcheroo_client_fb_set() takes an instance of struct fb_info as parameter, it really only needs the contained fbcon state. Moving the call to fbcon initialization is therefore cleaner than before. Only amdgpu, i915, nouveau and radeon support vga_switcheroo. For all other drivers, this change does nothing.
- Database specific
{ "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/68xxx/CVE-2025-68296.json" }- References
-
- https://git.kernel.org/stable/c/05814c389b53d2f3a0b9eeb90ba7a05ba77c4c2a
- https://git.kernel.org/stable/c/482330f8261b4bea8146d9bd69c1199e5dfcbb5c
- https://git.kernel.org/stable/c/711ebd961190def4c69ea24b2f0be75e995af24a
- https://git.kernel.org/stable/c/eb76d0f5553575599561010f24c277cc5b31d003
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/68xxx/CVE-2025-68296.json
- https://nvd.nist.gov/vuln/detail/CVE-2025-68296
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6a9ee8af344e3bd7dbd61e67037096cdf7f83289Fixed711ebd961190def4c69ea24b2f0be75e995af24aFixed482330f8261b4bea8146d9bd69c1199e5dfcbb5cFixed05814c389b53d2f3a0b9eeb90ba7a05ba77c4c2aFixedeb76d0f5553575599561010f24c277cc5b31d003