Evidence-led vulnerability intelligence · 2026-08-15 11:52 IST

CVE-2026-74331

In the Linux kernel, the following vulnerability has been resolved: firmware_loader: Fix recursive lock in device_cache_fw_images() A recursive locking deadlock can occur in the firmware loader's power management notification handler. During system suspend or hibernation preparation, fw_pm_notify() calls device_cache_fw_images(). This function acquires fw_lock to set the firmware cache state to FW_LOADER_START_CACHE and then iterates over all devices using dpm_for_each_dev() while still holding the lock. For each device, dev_cache_fw_image() schedules asynchronous work to cache the firmware. If memory allocation for the async work entry fails (e.g., in out-of-memory conditions), async_schedule_node_domain() falls back to executing the work function synchronously in the current thread. The synchronous execution path (__async_dev_cache_fw_image() -> cache_firmware() -> request_firmware() -> assign_fw()) attempts to acquire fw_lock again. Since the current thread already holds fw_lock, this results in a recursive locking deadlock. Fix this by releasing fw_lock immediately after updating the cache state and before calling dpm_for_each_dev(). The lock is only needed to protect the state update. Concurrent firmware requests will correctly see the FW_LOADER_START_CACHE state and use the piggyback mechanism, which is independently protected by its own fwc->name_lock.

UNRATED · N/ALinux

Executive briefing

The source record describes: In the Linux kernel, the following vulnerability has been resolved: firmware_loader: Fix recursive lock in device_cache_fw_images() A recursive locking deadlock can occur in the firmware loader's power management notification handler. During system suspend or hibernation preparation, fw_pm_notify() calls device_cache_fw_images(). This function acquires fw_lock to set the firmware cache state to FW_LOADER_START_CACHE and then iterates over all devices using dpm_for_each_dev() while still holding the lock. For each device, dev_cache_fw_image() schedules asynchronous work to cache the firmware. If memory allocation for the async work entry fails (e.g., in out-of-memory conditions), async_schedule_node_domain() falls back to executing the work function synchronously in the current thread. The synchronous execution path (__async_dev_cache_fw_image() -> cache_firmware() -> request_firmware() -> assign_fw()) attempts to acquire fw_lock again. Since the current thread already holds fw_lock, this results in a recursive locking deadlock. Fix this by releasing fw_lock immediately after updating the cache state and before calling dpm_for_each_dev(). The lock is only needed to protect the state update. Concurrent firmware requests will correctly see the FW_LOADER_START_CACHE state and use the piggyback mechanism, which is independently protected by its own fwc->name_lock. The practical risk depends on whether an affected product/version is present, reachable and configured in an exploitable way. Review the affected-product evidence and linked vendor advisories before assigning exposure status.

Assessment: Potential exposure only — validate the installed product, exact version, configuration and vendor applicability before treating an asset as confirmed vulnerable.

Evidence confidence: Limited Evidence-derived, not an exploitability verdict

Severity & attack characteristics

N/A / 10 ·

CVSS vector:

No CVSS vector is currently available in the source record.

Technical explanation & impact

The technical mechanism is not expanded beyond the source description unless a referenced advisory supplies additional evidence. Read the linked vendor/CERT advisories for root-cause detail.

Potential impact must be interpreted from the published CVSS impact metrics and the affected component. A CVSS impact score is not proof that a particular asset is exploitable.

Affected products and versions

NVD has not supplied machine-readable vulnerable CPE product/version entries for this CVE. This is an information gap, not proof that no products are affected. Check the vendor advisory references below.

Remediation & validation

  1. Identify exposure by comparing the affected product and version ranges with your asset inventory, SBOM and externally exposed services.
  2. Review the linked vendor security advisory or patch notes. Upgrade to a vendor-confirmed fixed release; do not infer a fixed version from the CVE description.
  3. Until patched, consider restricting network access or disabling the affected feature where operationally safe. These are temporary controls, not a substitute for a vendor fix.
  4. Validate the remediation with a version check and vulnerability rescan, then retain change evidence.

No fixed version is displayed unless it is explicitly established by a vendor advisory. Follow the vendor's release notes for exact product and branch applicability.

Vendor advisories, patches & exploit references

Information gaps & confidence notes

These gaps indicate missing source data. CVE Watch does not fill them with guessed product, exploit or patch details.

Last enrichment: 2026-11-07T16:42:43+00:00 · Source last modified: 2026-11-06T17:19:46.313

Open NVD record ← Back to CVE Watch

Threat intelligence, made actionable · CVE data sourced from the NVD