CVE-2024-42253: gpio: pca953x: fix pca953x_irq_bus_sync_unlock race

Severity: medium (CVSS 4.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-08-08 · updated 2026-08-04
Weakness: CWE-667

Description

In the Linux kernel, the following vulnerability has been resolved: gpio: pca953x: fix pca953x_irq_bus_sync_unlock race Ensure that `i2c_lock' is held when setting interrupt latch and mask in pca953x_irq_bus_sync_unlock() in order to avoid races. The other (non-probe) call site pca953x_gpio_set_multiple() ensures the lock is held before calling pca953x_write_regs(). The problem occurred when a request raced against irq_bus_sync_unlock() approximately once per thousand reboots on an i.MX8MP based system. * Normal case 0-0022: write register AI|3a {03,02,00,00,01} Input latch P0 0-0022: write register AI|49 {fc,fd,ff,ff,fe} Interrupt mask P0 0-0022: write register AI|08 {ff,00,00,00,00} Output P3 0-0022: write register AI|12 {fc,00,00,00,00} Config P3 * Race case 0-0022: write register AI|08 {ff,00,00,00,00} Output P3 0-0022: write register AI|08 {03,02,00,00,01} *** Wrong register *** 0-0022: write register AI|12 {fc,00,00,00,00} Config P3 0-0022: write register AI|49 {fc,fd,ff,ff,fe} Interrupt mask P0

Affected products

Linux kernel: before 6.1.101; from 6.2 before 6.6.42; from 6.7 before 6.9.11; 6.10-rc1, 6.10-rc2, 6.10-rc3, 6.10-rc4, 6.10-rc5 — fixed in 6.1.101, 6.6.42, 6.9.11

How to fix

Upgrade to a fixed version: Linux kernel 6.1.101, 6.6.42, 6.9.11. Check the vendor advisory for mitigations.

References

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