{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-90427", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.814Z", "datePublished": "2026-09-17T16:09:49.121Z", "dateUpdated": "2026-10-21T12:51:38.034Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:51:38.034Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/tegra241-cmdqv: Don't fall back to a freed smmu after devm_krealloc()\n\n__tegra241_cmdqv_probe() uses devm_krealloc() to grow @smmu into the larger\ntegra241_cmdqv, which frees the original @smmu once it relocates. A failure\nafter that returned NULL, and the caller then dereferenced the freed @smmu\non its fallback path.\n\nReturn an int and take @smmu by reference instead, then update *smmu to the\nreallocated pointer after devm_krealloc() succeeds, so the caller and its\nfallback path both use the live @smmu rather than the freed original." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.4, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The UAF is reached from arm_smmu_device_probe() → arm_smmu_impl_probe() → tegra241_cmdqv_probe() → __tegra241_cmdqv_probe() when ACPI IORT (acpi_iort_init()/iort_add_platform_device(\"arm-smmu-v3\")) or DT nvidia,tegra264-smmu binds the SMMU. No protocol message supplies the stale pointer; it is a local devm_krealloc() lifetime bug.\nAC:H - out_fallback uses the freed @smmu only if a relocating devm_krealloc() is followed by kzalloc_objs(cmdqv->vintfs) or request_threaded_irq() failing. arm_smmu_driver sets suppress_bind_attrs, CONFIG_ARM_SMMU_V3=y, and this probe never returns -EPROBE_DEFER, so a local attacker cannot re-enter it or reliably force those GFP_KERNEL/IRQ failures.\nPR:N - arm_smmu_device_probe() has no capable() check; tegra241_cmdqv_probe() runs from the platform .probe in kernel_init once IORT creates the arm-smmu-v3 device or DT matches nvidia,tegra264-smmu. No OS account or user-namespace capability is required to be on that path.\nUI:N - tegra241_cmdqv_probe()’s out_fallback dereference of the freed @smmu runs inside arm_smmu_device_probe() during automatic platform bind; no victim must mount a filesystem, open a device node, or load a module by hand.\nS:U - The use-after-free is of the host kernel arm_smmu_device that devm_krealloc() freed in __tegra241_cmdqv_probe(); out_fallback’s smmu->options write and the rest of arm_smmu_device_probe() stay in that kernel. This is not leftover SMMU translation tables or a guest/DMA walk of attacker-controlled IOMMU page tables.\nC:H - After a relocating devm_krealloc(), tegra241_cmdqv_probe() returns ERR_PTR(-ENODEV) and arm_smmu_impl_probe() hands the freed @smmu back to arm_smmu_device_probe(). That use-after-free of the SMMU object can be reclaimed and, per kernel UAF guidance, enables arbitrary kernel memory disclosure.\nI:H - out_fallback writes smmu->options through the freed pointer, then arm_smmu_device_probe() continues with arm_smmu_device_hw_probe(), arm_smmu_init_structures(), and iommu_device_register() on the same dangling arm_smmu_device, a write-after-free that yields heap-spray write and control-flow hijack primitives.\nA:H - out_fallback dereferences smmu->impl_dev and later SMMU probe/runtime uses the freed arm_smmu_device; that use-after-free oopses or panics the kernel even when not turned into a full exploit." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c" ], "versions": [ { "version": "918eb5c856f6ce4cf93b4b38e4b5e156905c5943", "lessThan": "ea2edb27ef2648d8687cd0fc3ec3ba1793436e7e", "status": "affected", "versionType": "git" }, { "version": "918eb5c856f6ce4cf93b4b38e4b5e156905c5943", "lessThan": "268cbe3a36ae57a2ec09601f343b92f6f092d505", "status": "affected", "versionType": "git" }, { "version": "918eb5c856f6ce4cf93b4b38e4b5e156905c5943", "lessThan": "86197679b293f0601c3331d545f99a70a7780aa9", "status": "affected", "versionType": "git" }, { "version": "918eb5c856f6ce4cf93b4b38e4b5e156905c5943", "lessThan": "d4d05f55e9da646ec03adfa77260eb46f4163749", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c" ], "versions": [ { "version": "6.12", "status": "affected" }, { "version": "0", "lessThan": "6.12", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.6", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "6.12.114" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "6.18.57" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "7.2.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/ea2edb27ef2648d8687cd0fc3ec3ba1793436e7e" }, { "url": "https://git.kernel.org/stable/c/268cbe3a36ae57a2ec09601f343b92f6f092d505" }, { "url": "https://git.kernel.org/stable/c/86197679b293f0601c3331d545f99a70a7780aa9" }, { "url": "https://git.kernel.org/stable/c/d4d05f55e9da646ec03adfa77260eb46f4163749" } ], "title": "iommu/tegra241-cmdqv: Don't fall back to a freed smmu after devm_krealloc()", "x_generator": { "engine": "bippy-1.2.0" } } } }