CVE-2026-64500

In the Linux kernel, the following vulnerability has been resolved:

iio: adc: lpc32xx: Initialize completion before requesting IRQ

In the report from Jaeyoung Chung:

lpc32xx_adc_probe() in drivers/iio/adc/lpc32xx_adc.c registers its interrupt handler with devm_request_irq() before it initializes st->completion with init_completion(). If an interrupt arrives after devm_request_irq() and before init_completion(), the handler calls complete() on an uninitialized completion, causing a kernel panic.

The probe path, in lpc32xx_adc_probe():

iodev = devm_iio_device_alloc(&pdev->dev, sizeof(*st)); /* st kzalloc-zeroed */
...
retval = devm_request_irq(&pdev->dev, irq, lpc32xx_adc_isr, 0,
                          LPC32XXAD_NAME, st);           /* register handler */
...
init_completion(&st->completion);                       /* initialize completion */

lpc32xx_adc_isr() calls complete():

complete(&st->completion);

If the device raises an interrupt before init_completion() runs, complete() acquires the uninitialized wait.lock and walks the zeroed task_list in swake_up_locked(). The zeroed task_list makes list_empty() return false, so swake_up_locked() dereferences a NULL list entry, triggering a KASAN wild-memory-access.

Fix the chance of a spurious IRQ causing an uninitialized pointer dereference by moving init_completion() above devm_request_irq().

Affected Software

References

• https://git.kernel.org/stable/c/0e33587967b356519aa6f220b5b43c6976320397
• https://git.kernel.org/stable/c/1ddf7b6ffb8ebb22b92a184a9eaa76277ef0c7cd
• https://git.kernel.org/stable/c/2f18c5551aa97ca7f39dbb151c67c9053ccadc17
• https://git.kernel.org/stable/c/48eccc6caed4e62c0f199ab3a3772fa969cd3b2d
• https://git.kernel.org/stable/c/7090c0d29708ee305022d0ea7b37612b33242fa2
• https://git.kernel.org/stable/c/820c4f15353efe9a9429ae86ccceeaf4e0e4e585
• https://git.kernel.org/stable/c/9e2e8b8cdfd37ae7c7a8a5c96c59e98a768731c4
• https://git.kernel.org/stable/c/e561b35633f450ee607e87a6401d97f156a0cd54