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CVE-2026-45902 Linux CVE debrief

A use-after-free vulnerability in the Linux kernel's BQ256xx power supply driver could allow system crashes or memory corruption during driver removal or probe. The issue stems from incorrect ordering of devm-managed resource allocation: the IRQ was requested before the power_supply handle registration, causing the power_supply to be freed before IRQ unregistration during teardown. This creates a race where an interrupt firing after power_supply deallocation but before IRQ handler removal calls power_supply_changed() with a freed handle. A similar race exists during probe where interrupts could fire before power_supply initialization. The fix reorders resource allocation so IRQ request occurs after power_supply registration, ensuring proper cleanup sequence.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-27
Original CVE updated
2026-05-27
Advisory published
2026-05-27
Advisory updated
2026-05-27

Who should care

Organizations running Linux systems with BQ256xx battery charger hardware, embedded Linux device manufacturers, and kernel maintainers backporting stable fixes

Technical summary

The BQ256xx power supply driver in the Linux kernel used devm_request_irq() before devm_power_supply_register(), violating devm resource ordering guarantees. During driver removal, devm resources free in reverse allocation order, so power_supply_unregister() runs before free_irq(). This window allows pending interrupts to invoke power_supply_changed() with a freed power_supply structure. The vulnerability also affects probe: interrupts can fire before power_supply registration completes, causing uninitialized pointer use. The fix moves devm_request_irq() after devm_power_supply_register(), ensuring the IRQ handler is unregistered before power_supply deallocation during teardown, and that power_supply is valid when interrupts can first fire.

Defensive priority

medium

Recommended defensive actions

  • Apply kernel patches from stable branches once available for your distribution
  • Monitor vendor security advisories for backported fixes
  • If running custom kernels with BQ256xx driver, prioritize updating to patched versions
  • Review systems using BQ256xx battery charger ICs for kernel update scheduling

Evidence notes

Vulnerability description and fix details sourced from official CVE record and NVD entry. Kernel commit references confirm the patch addresses the race condition by reordering devm_power_supply_register() before devm_request_irq().

Official resources

2026-05-27