{"id":"CVE-2026-80818","summary":"iommu/tegra241-cmdqv: Fix CMD_SYNC use-after-free on teardown","details":"In the Linux kernel, the following vulnerability has been resolved:\n\niommu/tegra241-cmdqv: Fix CMD_SYNC use-after-free on teardown\n\narm_smmu_impl_remove() is registered as a devres action in\narm_smmu_impl_probe(), before arm_smmu_init_queues() allocates\nsmmu-\u003ecmdq.q.base. On a devres unwind, whether a failed probe or an\nunbind, the queue is freed first and arm_smmu_impl_remove() then runs\ntegra241_cmdqv_remove_vintf(), whose VINTF deinit issues a CMD_SYNC on\nthe freed memory.\n\nObserved during testing with a QEMU hack that makes the VCMDQ fail to\nenable, so the impl reset fails and probe aborts into the devres unwind:\n\n platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: failed to enable, STATUS=0x00000000\n platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: GERRORN=0x0, GERROR=0x4, CONS=0x0\n platform NVDA200C:00: tegra241_cmdqv: VINTF0: VCMDQ0/LVCMDQ0: uncleared error detected, resetting\n arm-smmu-v3 arm-smmu-v3.0.auto: failed to reset impl\n arm-smmu-v3 arm-smmu-v3.0.auto: probe with driver arm-smmu-v3 failed with error -110\n Unable to handle kernel paging request at virtual address ffff8000891e0098\n ...\n Internal error: Oops: 0000000096000047 [#1] SMP\n ...\n Call trace:\n  arm_smmu_cmdq_issue_cmdlist+0x320/0x6fc (P)\n  tegra241_vcmdq_hw_deinit+0x98/0x168\n  tegra241_vintf_hw_deinit+0x5c/0x1b0\n  tegra241_cmdqv_remove_vintf+0x34/0xec\n  tegra241_cmdqv_remove+0x40/0x9c\n  arm_smmu_impl_remove+0x20/0x30\n  devm_action_release+0x14/0x20\n  devres_release_all+0xa8/0x110\n  device_unbind_cleanup+0x18/0x84\n  really_probe+0x1f0/0x29c\n\nDrop the VINTF deinit from tegra241_cmdqv_remove_vintf() so the unwind no\nlonger touches the freed queue. Quiesce the VINTFs earlier instead. Add a\ndevice_disable() impl op and run it from arm_smmu_disable_action() while\nthe CMDQ is still up. That handles a live unbind. A failed reset is already\nhandled because tegra241_vintf_hw_init() deinits the VINTF on its own error\npath. tegra241_cmdqv_remove_vintf() is also used by the iommufd viommu\ndestroy path, so quiesce there too.","modified":"2026-09-06T03:46:38.493966417Z","published":"2026-09-04T15:13:39.273Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80818.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/5994617e09ee6016c1b094f29d9c85cac944b477"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9ff145a25c5c8a26b06ef7cf558fb536b18bba6d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a94309bb99eaf0c6a2ace4927864486d19458eb5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d2ab08437e913d9e4dda4dfd0d327446ec8717fc"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80818.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80818"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7"},{"fixed":"d2ab08437e913d9e4dda4dfd0d327446ec8717fc"},{"fixed":"a94309bb99eaf0c6a2ace4927864486d19458eb5"},{"fixed":"5994617e09ee6016c1b094f29d9c85cac944b477"},{"fixed":"9ff145a25c5c8a26b06ef7cf558fb536b18bba6d"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80818.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.17.0"},{"fixed":"6.18.47"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.11"}]},{"type":"ECOSYSTEM","events":[{"introduced":"7.2.0"},{"fixed":"7.2.1"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80818.json"}}],"schema_version":"1.9.0"}