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

iommu/tegra241-cmdqv: Publish an LVCMDQ only after it is fully initialized

tegra241_vintf_init_lvcmdq() stores the freshly allocated vcmdq pointer to
the vintf->lvcmdqs[] array, before tegra241_vcmdq_alloc_smmu_cmdq() builds
the vcmdq->cmdq. The error ISR dereferences that cmdq, so a latched LVCMDQ
error (e.g. one inherited across a kexec) firing in this window would make
tegra241_vintf0_handle_error() pass the still-zeroed arm_smmu_cmdq down to
__arm_smmu_cmdq_skip_err(), dereferencing NULL queue register pointers.

Drop the store from tegra241_vintf_init_lvcmdq() and publish the vcmdq at
the end of the allocation instead, with an smp_store_release() that pairs
with an smp_load_acquire() in the ISR, which can see a fully built LVCMDQ
or NULL.

The user-owned LVCMDQ allocation moves accordingly, publishing the vcmdq
once tegra241_vcmdq_hw_init_user() succeeds, using a plain store since a
user VINTF's lvcmdqs[] has no lockless reader -- the error ISR only walks
the VINTF0 array.

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Source ID Title
Debian DLA Debian DLA DLA-4817-1 linux-6.12 security update
Debian DSA Debian DSA DSA-6528-1 linux security update
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 21 Sep 2026 13:30:00 +0000


Sat, 19 Sep 2026 13:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-476

Thu, 17 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: iommu/tegra241-cmdqv: Publish an LVCMDQ only after it is fully initialized tegra241_vintf_init_lvcmdq() stores the freshly allocated vcmdq pointer to the vintf->lvcmdqs[] array, before tegra241_vcmdq_alloc_smmu_cmdq() builds the vcmdq->cmdq. The error ISR dereferences that cmdq, so a latched LVCMDQ error (e.g. one inherited across a kexec) firing in this window would make tegra241_vintf0_handle_error() pass the still-zeroed arm_smmu_cmdq down to __arm_smmu_cmdq_skip_err(), dereferencing NULL queue register pointers. Drop the store from tegra241_vintf_init_lvcmdq() and publish the vcmdq at the end of the allocation instead, with an smp_store_release() that pairs with an smp_load_acquire() in the ISR, which can see a fully built LVCMDQ or NULL. The user-owned LVCMDQ allocation moves accordingly, publishing the vcmdq once tegra241_vcmdq_hw_init_user() succeeds, using a plain store since a user VINTF's lvcmdqs[] has no lockless reader -- the error ISR only walks the VINTF0 array.
Title iommu/tegra241-cmdqv: Publish an LVCMDQ only after it is fully initialized
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-19T09:03:33.781Z

Reserved: 2026-09-11T19:38:34.815Z

Link: CVE-2026-90430

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-17T17:17:47.997

Modified: 2026-10-19T09:19:37.310

Link: CVE-2026-90430

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-19T15:00:11Z

Weaknesses