drm/fb-helper: defer setup when fbdev_probe() fails, not just on -EAGAIN
In the Linux kernel, the following vulnerability has been resolved: drm/fb-helper: defer setup when fbdev_probe() fails, not just on -EAGAIN __drm_fb_helper_initial_config_and_unlock() calls drm_client_modeset_probe() first, which already fills in each mode_set->mode/num_connectors for every connected output, and only afterwards calls drm_fb_helper_single_fb_probe() to create fb_helper->fb and wire it into those mode_sets via drm_setup_crtcs_fb(). If drm_fb_helper_single_fb_probe() fails with anything other than -EAGAIN (e.g. dev->driver->fbdev_probe() itself fails), the function bails out before drm_setup_crtcs_fb() runs and before setting fb_helper->deferred_setup. The client is left with mode_sets that have a mode and connectors but mode_set->fb == NULL, and nothing marks this fb_helper as needing a retry. __drm_fb_helper_restore_fbdev_mode_unlocked() only skips committing when fb_helper->deferred_setup is set, so a later .restore() call (drm_lastclose() on process exit, in this report) commits the stale mode_set through drm_client_modeset_commit() -> drm_client_modeset_commit_atomic() -> __drm_atomic_helper_set_config(), which hits WARN_ON(!set->fb). Mark fb_helper->deferred_setup on any drm_fb_helper_single_fb_probe() failure, not just -EAGAIN, so restore keeps skipping the commit until a later hotplug event successfully re-probes and re-populates mode_set->fb. The real error code is still returned to the caller unchanged.
CVE-2026-99007
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-99007
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "ca91a2758fcef6635626993557dd51cfbb6dd134",
"lessThan": "4a2006c675758f0c765b36fec6b49d17e89159cf",
"versionType": "git"
},
{
"status": "affected",
"version": "ca91a2758fcef6635626993557dd51cfbb6dd134",
"lessThan": "3b303696f61461b3569019d7fcac6a646652b2b4",
"versionType": "git"
},
{
"status": "affected",
"version": "ca91a2758fcef6635626993557dd51cfbb6dd134",
"lessThan": "4e7b508c7c60dec7a86b7eb2a1b7e6d174afa457",
"versionType": "git"
},
{
"status": "affected",
"version": "ca91a2758fcef6635626993557dd51cfbb6dd134",
"lessThan": "d510ed273854177f0a3ed330145858b2fe667f81",
"versionType": "git"
},
{
"status": "affected",
"version": "ca91a2758fcef6635626993557dd51cfbb6dd134",
"lessThan": "755c94d178b7e972bb766199d34e4ba4f63a89eb",
"versionType": "git"
}
],
"programFiles": [
"drivers/gpu/drm/drm_fb_helper.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.14"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.14",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.57",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.11",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/gpu/drm/drm_fb_helper.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-99007
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #52849 · Revision 1
- Added to Heist Feed
- Publisher date