{"id":"CVE-2026-90425","state":"PUBLISHED","title":"iommu/tegra241-cmdqv: Require exactly one Stream ID for a vSID","description":"In the Linux kernel, the following vulnerability has been resolved:\n\niommu/tegra241-cmdqv: Require exactly one Stream ID for a vSID\n\ntegra241_vintf_init_vsid() maps a guest vSID to a single physical Stream ID\ntaken from master->streams[0], and only warns when the device does not have\nexactly one stream. A device with several streams gets only its first one\nmapped, so a guest vSID invalidation cannot reach the others' ATC and IOTLB\nentries; a device with none makes master->streams a ZERO_SIZE_PTR, read out\nof bounds.\n\nReject the mapping with -EOPNOTSUPP if master->num_streams is not one.","publishedAt":"2026-09-17T16:09:47.810Z","updatedAt":"2026-10-19T09:03:29.009Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7","status":"affected","lessThan":"9b37afb2d34d99ec4f8db28134181b5a8ec9a4a5","versionType":"git"},{"version":"4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7","status":"affected","lessThan":"0b139ec4641c7d4163d8e345c26cc630e24fa43b","versionType":"git"},{"version":"4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7","status":"affected","lessThan":"fb292bfc9be936dade7eef7ec5762de1201983d8","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.17","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.17","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c"]}],"references":["https://git.kernel.org/stable/c/9b37afb2d34d99ec4f8db28134181b5a8ec9a4a5","https://git.kernel.org/stable/c/0b139ec4641c7d4163d8e345c26cc630e24fa43b","https://git.kernel.org/stable/c/fb292bfc9be936dade7eef7ec5762de1201983d8"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/90xxx/CVE-2026-90425.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90425","state":"PUBLISHED","datePublished":"2026-09-17T16:09:47.810Z","dateUpdated":"2026-10-19T09:03:29.009Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.814Z"},"containers":{"cna":{"title":"iommu/tegra241-cmdqv: Require exactly one Stream ID for a vSID","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\niommu/tegra241-cmdqv: Require exactly one Stream ID for a vSID\n\ntegra241_vintf_init_vsid() maps a guest vSID to a single physical Stream ID\ntaken from master->streams[0], and only warns when the device does not have\nexactly one stream. A device with several streams gets only its first one\nmapped, so a guest vSID invalidation cannot reach the others' ATC and IOTLB\nentries; a device with none makes master->streams a ZERO_SIZE_PTR, read out\nof bounds.\n\nReject the mapping with -EOPNOTSUPP if master->num_streams is not one."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7","status":"affected","lessThan":"9b37afb2d34d99ec4f8db28134181b5a8ec9a4a5","versionType":"git"},{"version":"4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7","status":"affected","lessThan":"0b139ec4641c7d4163d8e345c26cc630e24fa43b","versionType":"git"},{"version":"4dc0d12474f9d4833c3dd96b73d61e406d3f5dc7","status":"affected","lessThan":"fb292bfc9be936dade7eef7ec5762de1201983d8","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.17","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.17","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/9b37afb2d34d99ec4f8db28134181b5a8ec9a4a5"},{"url":"https://git.kernel.org/stable/c/0b139ec4641c7d4163d8e345c26cc630e24fa43b"},{"url":"https://git.kernel.org/stable/c/fb292bfc9be936dade7eef7ec5762de1201983d8"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - tegra241_vintf_init_vsid() is reached only via iommufd_fops_ioctl() dispatching IOMMU_VDEVICE_ALLOC to iommufd_vdevice_alloc_ioctl() after VFIO_DEVICE_BIND_IOMMUFD. master->num_streams comes from the bound device's IORT/DT fwspec, not from a network protocol message.\nAC:L - Once a CMDQV master is bound, IOMMU_VDEVICE_ALLOC always does writel(master->streams[0].id, SID_REPLACE). pci_for_each_dma_alias (iort_pci_iommu_init) yields num_streams>1 and maps only the first SID; num_streams==0 reads ZERO_SIZE_PTR. The attacker issues that ioctl; no race or uninfluenced layout is required.\nPR:L - iommufd_fops_open() and iommufd_vdevice_alloc_ioctl() have no capable() check (/dev/iommu 0660). A tenant or unprivileged QEMU user granted VFIO access on NVIDIA Grace can VFIO_DEVICE_BIND_IOMMUFD, IOMMU_VIOMMU_ALLOC type TEGRA241_CMDQV, and IOMMU_VDEVICE_ALLOC without init-namespace root.\nUI:N - The attacker opens iommufd, binds the assigned device, allocates the TEGRA241_CMDQV vIOMMU and vDEVICE, then issues guest ATC_INV on the mmap'd VCMDQ themselves. No separate victim action such as mounting a filesystem is required.\nS:C - tegra241_vintf_init_vsid() programs SID_REPLACE/SID_MATCH only for master->streams[0], so CMDQV HW rewrite of guest ATC_INV (no VMEXIT) and arm_vsmmu_cache_invalidate cannot reach the other streams' ATC/IOTLB. That is an IOMMU/DMA boundary bypass: stale translations let device DMA reach host memory outside the guest domain.\nC:H - After a guest IOVA unmap, stale ATC/IOTLB entries on the unprogrammed physical SIDs let the passthrough device DMA-read recycled host pages. That is an arbitrary host-memory disclosure through the IOMMU, not a bounded kernel-pointer leak.\nI:H - The same stale translations allow DMA writes into recycled host pages, and programming only one of several SIDs leaves ATC_INV operating on the wrong Stream ID, corrupting IOMMU translation state with an arbitrary write suitable for control-flow hijack.\nA:H - When fwspec->num_ids is 0, arm_smmu_insert_master() sets master->streams to ZERO_SIZE_PTR ((void *)16) and tegra241_vintf_init_vsid() dereferences streams[0].id, which slab.h documents as a distinct access fault/oops; missed invalidations also let hostile DMA panic the host."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:03:29.009Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}