CVE-2026-90426

What the bug is

tegra241_cmdqv_remove() tears each VINTF down first, then calls free_irq(). Tearing a VINTF down frees vintf0 and clears cmdqv->vintfs[0]. An error in that window makes tegra241_cmdqv_isr() read the stale slot and hand it to tegra241_vintf0_handle_error(), which dereferences a NULL or freed pointer. Free the IRQ before tearing the VINTFs down. free_irq() waits for in-flight handlers to finish and blocks new ones, so no ISR can observe a VINTF as it is torn down. Note: a user-owned VINTF (viommu) could outlive this teardown, which unmaps cmdqv->base and frees cmdqv->vintfs, so a later viommu close then touches freed memory. This is neither introduced nor fixed here: a physical IOMMU is not a pluggable device, so iommufd by design holds no reference on the one behind a viommu, and this teardown is not expected while that viommu is still alive.

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c

What this is

TEGRA IOMMU DRIVERSMAINTAINERS section matched on drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c · linux-tegra@vger.kernel.org · Supported

Check it on the machine

grep -wE 'CONFIG_ARM_SMMU_V3|CONFIG_TEGRA241_CMDQV' /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

Show whether Debian builds this, per release

Debian does not build this code in 4 releases. The build rule could not be established for 1 release, so nothing is claimed about those.

• bookworm?
• trixie, forky, sid, bookworm · linux-6.12n

?

not established - no Makefile entry for the affected file

n

not enabled on any flavour - this release does not build the code

Where a release above reads "not established", no build rule for the affected file was found in that release's kernel tree. That is a gap in this lookup, not a finding that the code is absent.

Build switches

CONFIG_ARM_SMMU_V3, CONFIG_TEGRA241_CMDQV

Reads as

all on means the file is compiled; any one off means it is not.

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-09-17 (31 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 10.3% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

unimportantsource

Subsystem

drivers/iommu

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
6.12	6.12.110	076a4f5b1fc2
6.12	6.18.52	735698e81f79
6.12	7.2.6	421f5ab135cd
6.12	7.3	61f0d437988e

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