In the Linux kernel, the following vulnerability has been resolved:
iommu/tegra241-cmdqv: Fix CMD_SYNC use-after-free on teardown
arm_smmu_impl_remove() is registered as a devres action in
arm_smmu_impl_probe(), before arm_smmu_init_queues() allocates
smmu->cmdq.q.base. On a devres unwind, whether a failed probe or an
unbind, the queue is freed first and arm_smmu_impl_remove() then runs
tegra241_cmdqv_remove_vintf(), whose VINTF deinit issues a CMD_SYNC on
the freed memory.
Observed during testing with a QEMU hack that makes the VCMDQ fail to
enable, so the impl reset fails and probe aborts into the devres unwind:
platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: failed to enable, STATUS=0x00000000
platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: GERRORN=0x0, GERROR=0x4, CONS=0x0
platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: uncleared error detected, resetting
arm-smmu-v3 arm-smmu-v3.0.auto: failed to reset impl
arm-smmu-v3 arm-smmu-v3.0.auto: probe with driver arm-smmu-v3 failed with error -110
Unable to handle kernel paging request at virtual address ffff8000891e0098
...
Internal error: Oops: 0000000096000047 [#1] SMP
...
Call trace:
arm_smmu_cmdq_issue_cmdlist+0x320/0x6fc (P)
tegra241_vcmdq_hw_deinit+0x98/0x168
tegra241_vintf_hw_deinit+0x5c/0x1b0
tegra241_cmdqv_remove_vintf+0x34/0xec
tegra241_cmdqv_remove+0x40/0x9c
arm_smmu_impl_remove+0x20/0x30
devm_action_release+0x14/0x20
devres_release_all+0xa8/0x110
device_unbind_cleanup+0x18/0x84
really_probe+0x1f0/0x29c
Drop the VINTF deinit from tegra241_cmdqv_remove_vintf() so the unwind no
longer touches the freed queue. Quiesce the VINTFs earlier instead. Add a
device_disable() impl op and run it from arm_smmu_disable_action() while
the CMDQ is still up. That handles a live unbind. A failed reset is already
handled because tegra241_vintf_hw_init() deinits the VINTF on its own error
path. tegra241_cmdqv_remove_vintf() is also used by the iommufd viommu
destroy path, so quiesce there too.
iommu/tegra241-cmdqv: Fix CMD_SYNC use-after-free on teardown
arm_smmu_impl_remove() is registered as a devres action in
arm_smmu_impl_probe(), before arm_smmu_init_queues() allocates
smmu->cmdq.q.base. On a devres unwind, whether a failed probe or an
unbind, the queue is freed first and arm_smmu_impl_remove() then runs
tegra241_cmdqv_remove_vintf(), whose VINTF deinit issues a CMD_SYNC on
the freed memory.
Observed during testing with a QEMU hack that makes the VCMDQ fail to
enable, so the impl reset fails and probe aborts into the devres unwind:
platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: failed to enable, STATUS=0x00000000
platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: GERRORN=0x0, GERROR=0x4, CONS=0x0
platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: uncleared error detected, resetting
arm-smmu-v3 arm-smmu-v3.0.auto: failed to reset impl
arm-smmu-v3 arm-smmu-v3.0.auto: probe with driver arm-smmu-v3 failed with error -110
Unable to handle kernel paging request at virtual address ffff8000891e0098
...
Internal error: Oops: 0000000096000047 [#1] SMP
...
Call trace:
arm_smmu_cmdq_issue_cmdlist+0x320/0x6fc (P)
tegra241_vcmdq_hw_deinit+0x98/0x168
tegra241_vintf_hw_deinit+0x5c/0x1b0
tegra241_cmdqv_remove_vintf+0x34/0xec
tegra241_cmdqv_remove+0x40/0x9c
arm_smmu_impl_remove+0x20/0x30
devm_action_release+0x14/0x20
devres_release_all+0xa8/0x110
device_unbind_cleanup+0x18/0x84
really_probe+0x1f0/0x29c
Drop the VINTF deinit from tegra241_cmdqv_remove_vintf() so the unwind no
longer touches the freed queue. Quiesce the VINTFs earlier instead. Add a
device_disable() impl op and run it from arm_smmu_disable_action() while
the CMDQ is still up. That handles a live unbind. A failed reset is already
handled because tegra241_vintf_hw_init() deinits the VINTF on its own error
path. tegra241_cmdqv_remove_vintf() is also used by the iommufd viommu
destroy path, so quiesce there too.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
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| Linux | Linux | affected |
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Fixes
Solution
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Workaround
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References
History
Fri, 04 Sep 2026 15:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: iommu/tegra241-cmdqv: Fix CMD_SYNC use-after-free on teardown arm_smmu_impl_remove() is registered as a devres action in arm_smmu_impl_probe(), before arm_smmu_init_queues() allocates smmu->cmdq.q.base. On a devres unwind, whether a failed probe or an unbind, the queue is freed first and arm_smmu_impl_remove() then runs tegra241_cmdqv_remove_vintf(), whose VINTF deinit issues a CMD_SYNC on the freed memory. Observed during testing with a QEMU hack that makes the VCMDQ fail to enable, so the impl reset fails and probe aborts into the devres unwind: platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: failed to enable, STATUS=0x00000000 platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: GERRORN=0x0, GERROR=0x4, CONS=0x0 platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: uncleared error detected, resetting arm-smmu-v3 arm-smmu-v3.0.auto: failed to reset impl arm-smmu-v3 arm-smmu-v3.0.auto: probe with driver arm-smmu-v3 failed with error -110 Unable to handle kernel paging request at virtual address ffff8000891e0098 ... Internal error: Oops: 0000000096000047 [#1] SMP ... Call trace: arm_smmu_cmdq_issue_cmdlist+0x320/0x6fc (P) tegra241_vcmdq_hw_deinit+0x98/0x168 tegra241_vintf_hw_deinit+0x5c/0x1b0 tegra241_cmdqv_remove_vintf+0x34/0xec tegra241_cmdqv_remove+0x40/0x9c arm_smmu_impl_remove+0x20/0x30 devm_action_release+0x14/0x20 devres_release_all+0xa8/0x110 device_unbind_cleanup+0x18/0x84 really_probe+0x1f0/0x29c Drop the VINTF deinit from tegra241_cmdqv_remove_vintf() so the unwind no longer touches the freed queue. Quiesce the VINTFs earlier instead. Add a device_disable() impl op and run it from arm_smmu_disable_action() while the CMDQ is still up. That handles a live unbind. A failed reset is already handled because tegra241_vintf_hw_init() deinits the VINTF on its own error path. tegra241_cmdqv_remove_vintf() is also used by the iommufd viommu destroy path, so quiesce there too. | |
| Title | iommu/tegra241-cmdqv: Fix CMD_SYNC use-after-free on teardown | |
| 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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MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-04T15:13:39.273Z
Reserved: 2026-08-26T14:34:25.795Z
Link: CVE-2026-80818
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-09-04T16:18:09.453
Modified: 2026-09-04T16:18:09.453
Link: CVE-2026-80818
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.