CVE-2026-23085
Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
04/02/2026
Last modified:
06/02/2026
Description
In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
irqchip/gic-v3-its: Avoid truncating memory addresses<br />
<br />
On 32-bit machines with CONFIG_ARM_LPAE, it is possible for lowmem<br />
allocations to be backed by addresses physical memory above the 32-bit<br />
address limit, as found while experimenting with larger VMSPLIT<br />
configurations.<br />
<br />
This caused the qemu virt model to crash in the GICv3 driver, which<br />
allocates the &#39;itt&#39; object using GFP_KERNEL. Since all memory below<br />
the 4GB physical address limit is in ZONE_DMA in this configuration,<br />
kmalloc() defaults to higher addresses for ZONE_NORMAL, and the<br />
ITS driver stores the physical address in a 32-bit &#39;unsigned long&#39;<br />
variable.<br />
<br />
Change the itt_addr variable to the correct phys_addr_t type instead,<br />
along with all other variables in this driver that hold a physical<br />
address.<br />
<br />
The gicv5 driver correctly uses u64 variables, while all other irqchip<br />
drivers don&#39;t call virt_to_phys or similar interfaces. It&#39;s expected that<br />
other device drivers have similar issues, but fixing this one is<br />
sufficient for booting a virtio based guest.
Impact
References to Advisories, Solutions, and Tools
- https://git.kernel.org/stable/c/03faa61eb4b9ca9aa09bd91d4c3773d8e7b1ac98
- https://git.kernel.org/stable/c/084ba3b99f2dfd991ce7e84fb17117319ec3cd9f
- https://git.kernel.org/stable/c/1b323391560354d8c515de8658b057a1daa82adb
- https://git.kernel.org/stable/c/85215d633983233809f7d4dad163b953331b8238
- https://git.kernel.org/stable/c/8d76a7d89c12d08382b66e2f21f20d0627d14859
- https://git.kernel.org/stable/c/e2f9c751f73a2d5bb62d94ab030aec118a811f27
- https://git.kernel.org/stable/c/e332b3b69e5b3acf07204a4b185071bab15c2b88



