Description
The user-mode syscall verifiers for the charger driver API in drivers/charger/charger_handlers.c did not inspect the prop argument before copying union charger_propval across the user/kernel boundary. Two members of that union are function pointers — status_notification (CHARGER_PROP_STATUS_NOTIFICATION) and online_notification (CHARGER_PROP_ONLINE_NOTIFICATION), declared in include/zephyr/drivers/charger.h — and z_vrfy_charger_set_prop() forwarded the caller-supplied union verbatim to the driver's set_property callback for any property. z_vrfy_charger_get_prop() had the mirror defect and copied the stored kernel callback address back out to user memory.

With CONFIG_USERSPACE enabled, any user-mode thread that has been granted a charger device object could call charger_set_prop() with CHARGER_PROP_STATUS_NOTIFICATION or CHARGER_PROP_ONLINE_NOTIFICATION and an arbitrary pointer value. Drivers that implement these properties — drivers/charger/charger_max20335.c, drivers/charger/charger_pf1550.c and drivers/charger/charger_bq2518x.c — store the pointer in device data and later invoke it from their interrupt work handlers, which run in supervisor mode, on any charger state change such as a cable plug/unplug.

The result is a control-flow hijack at kernel privilege from an unprivileged thread, defeating the isolation that CONFIG_USERSPACE is meant to provide; the read path additionally disclosed a kernel code address to user mode, and clearing a notifier installed by a supervisor thread let user mode suppress charger notifications. Supervisor-mode callers of charger_set_prop()/charger_get_prop() are unaffected.

The fix makes both verifiers reject the two notifier properties outright — including when the supplied callback is NULL, since the notifiers are device state — and adds a BUILD_ASSERT on CHARGER_PROP_COMMON_COUNT so that new properties force a re-review of the union's user-mode safety.
Published: 2026-11-12
Score: 7.8 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Thu, 12 Nov 2026 15:30:00 +0000

Type Values Removed Values Added
Description The user-mode syscall verifiers for the charger driver API in drivers/charger/charger_handlers.c did not inspect the prop argument before copying union charger_propval across the user/kernel boundary. Two members of that union are function pointers — status_notification (CHARGER_PROP_STATUS_NOTIFICATION) and online_notification (CHARGER_PROP_ONLINE_NOTIFICATION), declared in include/zephyr/drivers/charger.h — and z_vrfy_charger_set_prop() forwarded the caller-supplied union verbatim to the driver's set_property callback for any property. z_vrfy_charger_get_prop() had the mirror defect and copied the stored kernel callback address back out to user memory. With CONFIG_USERSPACE enabled, any user-mode thread that has been granted a charger device object could call charger_set_prop() with CHARGER_PROP_STATUS_NOTIFICATION or CHARGER_PROP_ONLINE_NOTIFICATION and an arbitrary pointer value. Drivers that implement these properties — drivers/charger/charger_max20335.c, drivers/charger/charger_pf1550.c and drivers/charger/charger_bq2518x.c — store the pointer in device data and later invoke it from their interrupt work handlers, which run in supervisor mode, on any charger state change such as a cable plug/unplug. The result is a control-flow hijack at kernel privilege from an unprivileged thread, defeating the isolation that CONFIG_USERSPACE is meant to provide; the read path additionally disclosed a kernel code address to user mode, and clearing a notifier installed by a supervisor thread let user mode suppress charger notifications. Supervisor-mode callers of charger_set_prop()/charger_get_prop() are unaffected. The fix makes both verifiers reject the two notifier properties outright — including when the supplied callback is NULL, since the notifiers are device state — and adds a BUILD_ASSERT on CHARGER_PROP_COMMON_COUNT so that new properties force a re-review of the union's user-mode safety.
Title Arbitrary supervisor-mode function pointer injection via charger_set_prop() syscall in the charger driver API
Weaknesses CWE-822
References
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Subscriptions

No data.

cve-icon MITRE

Status: PUBLISHED

Assigner: zephyr

Published:

Updated: 2026-11-12T15:19:20.012Z

Reserved: 2026-09-14T16:03:57.414Z

Link: CVE-2026-91007

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-11-12T16:19:21.250

Modified: 2026-11-12T16:19:21.370

Link: CVE-2026-91007

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses
  • CWE-822

    Untrusted Pointer Dereference