CVE-2026-98324 dmaengine: pxa: fix double counting of the hw descriptors
A logic error in the Linux kernel PXA DMA driver causes double counting of descriptors, potentially leading to memory corruption or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98324?
CVE-2026-98324 is a high-severity vulnerability in Linux, published on 6 Oct 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:
dmaengine: pxa: fix double counting of the hw descriptors
pxad_alloc_desc() was converted from
kzalloc(struct_size(sw_desc, hw_desc, nb_hw_desc), GFP_NOWAIT)
to kzalloc_flex(), which sets the __counted_by() counter sw_desc->nb_desc itself - but only where the compiler has __builtin_counted_by_ref(), so from gcc 15.1 or clang 22.1 on. The loop below it still increments nb_desc, which makes it come out doubled there and correct elsewhere.
nb_desc is what pxad_free_desc() iterates over and what set_updater_desc() indexes from, so set it explicitly and drop the increment. The error path has to lower it to the number of descriptors allocated so far, otherwise pxad_free_desc() would free entries that were never allocated.
Which versions are affected by CVE-2026-98324?
How do I fix CVE-2026-98324?
Apply the vendor's patch.
Is CVE-2026-98324 being exploited?
There is no known exploitation of CVE-2026-98324 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-98324, GHSA-wrvr-2vch-mjpj, UBUNTU-CVE-2026-98324.