{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-68257", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.378Z", "datePublished": "2026-08-10T12:01:30.547Z", "dateUpdated": "2026-08-18T06:55:54.208Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-18T06:55:54.208Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdkfd: fix 32-bit overflow in CWSR total size calculation\n\ntotal_cwsr_size was computed in 32-bit before being used as a BO/SVM\nallocation size.\nWith large ctx_save_restore_area_size and debug_memory_size\nmultiplied by the XCC count, the product can wrap,\nyielding an undersized CWSR save area that firmware later overruns.\n\nPromote total_cwsr_size to u64 and use check_add_overflow()/\ncheck_mul_overflow() in both kfd_queue_acquire_buffers() and\nkfd_queue_release_buffers().\n\n(cherry picked from commit 319f7e13423ae3f486b9aea82f9ad2d6af0ee608)" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - Triggered through the AMDKFD_IOC_CREATE_QUEUE ioctl on the local /dev/kfd character device; the attacker-controlled ctx_save_restore_size field comes straight from the ioctl argument struct with no remote reachability.\nAC:L - The overflow is pure deterministic arithmetic on a value the attacker fully controls — passing ctx_save_restore_size near 2^32 (or /NUM_XCC on multi-XCC MI300 parts) reliably wraps total_cwsr_size to 0 or a small value on every attempt, with no race or layout dependency.\nPR:L - Requires only an unprivileged local account with access to /dev/kfd, which is granted to the render group and is routinely available to ordinary users on ROCm hosts, GPU compute nodes, containers, Steam Deck/desktop and Chrome OS style systems; no capabilities are checked on this path.\nUI:N - The attacker creates the malicious compute queue entirely from its own process via a single ioctl; no action by any other user or administrator is needed.\nS:U - The undersized CWSR area and the resulting firmware overrun stay within the kernel/GPU driver security authority of the same machine; there is no hypervisor or IOMMU boundary crossed.\nC:H - With validation bypassed, CP firmware save/restore reads span memory adjacent to the tiny validated buffer and load it into wave state the attacker's shader can read back, and get_wave_state copies per-XCC control-stack contents out of the unvalidated region, giving a broad out-of-bounds disclosure primitive.\nI:H - The queue is programmed with the full unwrapped save size and per-XCC base offsets, so firmware performs large out-of-bounds writes of wave/control-stack data beyond the buffer that was actually validated and reference-counted, and the bypassed queue_refcount lets those buffers be unmapped or freed while the queue is live — an attacker-influenced memory-corruption primitive.\nA:H - Overrunning the CWSR save area drives the GPU into unmapped VA on preemption, causing VM faults, queue hangs and driver-initiated GPU resets that take down all GPU workloads on the machine, including other tenants on shared compute nodes." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/gpu/drm/amd/amdkfd/kfd_queue.c" ], "versions": [ { "version": "325aa07165394b8e866ffe9ec1d4c99d9195b2f2", "lessThan": "b88ffe6593607364a8c06a48c6f29e55437cdf8e", "status": "affected", "versionType": "git" }, { "version": "d15deafab5d722afb9e2f83c5edcdef9d9d98bd1", "lessThan": "abce3276c57e36c955627307469b9f009057a467", "status": "affected", "versionType": "git" }, { "version": "d15deafab5d722afb9e2f83c5edcdef9d9d98bd1", "lessThan": "865532d54eb57b660b1cb1b0e1755776ce21b849", "status": "affected", "versionType": "git" }, { "version": "d15deafab5d722afb9e2f83c5edcdef9d9d98bd1", "lessThan": "2b0386d4293920e690c0e017708f999b93cc729b", "status": "affected", "versionType": "git" }, { "version": "63600103d2ac5c09fdeec5b931b396e4e0efd5d8", "status": "affected", "versionType": "git" }, { "version": "6.12.59", "lessThan": "6.12.101", "status": "affected", "versionType": "semver" }, { "version": "6.17.9", "lessThan": "6.18", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/gpu/drm/amd/amdkfd/kfd_queue.c" ], "versions": [ { "version": "6.18", "status": "affected" }, { "version": "0", "lessThan": "6.18", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "6.12.59", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18", "versionEndExcluding": "6.18.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18", "versionEndExcluding": "7.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.17.9" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/b88ffe6593607364a8c06a48c6f29e55437cdf8e" }, { "url": "https://git.kernel.org/stable/c/abce3276c57e36c955627307469b9f009057a467" }, { "url": "https://git.kernel.org/stable/c/865532d54eb57b660b1cb1b0e1755776ce21b849" }, { "url": "https://git.kernel.org/stable/c/2b0386d4293920e690c0e017708f999b93cc729b" } ], "title": "drm/amdkfd: fix 32-bit overflow in CWSR total size calculation", "x_generator": { "engine": "bippy-1.2.0" } } } }