CVE-2026-90124 irqchip/renesas-rzg2l: Fix loss of interrupt
A race condition in the Renesas RZ/G2L interrupt controller driver can cause loss of interrupts, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90124?
CVE-2026-90124 is a vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
irqchip/renesas-rzg2l: Fix loss of interrupt
rzg2l_clear_irq_int() and rzg2l_clear_tint_int() perform a read-modify-write on the ISCR/TSCR status registers to clear the bit for the interrupt just handled. Since these registers are write-0-to-clear per bit, this is racy:
If another interrupt's status bit gets set between the read and the write, that bit is written back as 0 by the software-constructed value, clearing an interrupt that hasn't been serviced yet and losing it.
This can be reproduced by triggering multiple interrupts at once, e.g.:
gpioset -c gpiochip0 355=0 353=0 328=0 352=0
Fix this by writing back only the bit being cleared, with all other bits set to 1, instead of read-modify-writing the whole register. Since 1-bits are left unchanged by hardware, concurrently-set status bits for other interrupts are preserved.
Which versions are affected by CVE-2026-90124?
How do I fix CVE-2026-90124?
Apply the vendor's patch.
Is CVE-2026-90124 being exploited?
There is no known exploitation of CVE-2026-90124 in the wild and no public exploit code.
Sources
Also known as AZL-102216, BELL-CVE-2026-90124, DEBIAN-CVE-2026-90124, GHSA-h8c5-9rgx-f76h, UBUNTU-CVE-2026-90124.