{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-40172", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.177Z", "datePublished": "2025-11-12T10:53:49.245Z", "dateUpdated": "2026-08-05T12:08:17.861Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:08:17.861Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\naccel/qaic: Treat remaining == 0 as error in find_and_map_user_pages()\n\nCurrently, if find_and_map_user_pages() takes a DMA xfer request from the\nuser with a length field set to 0, or in a rare case, the host receives\nQAIC_TRANS_DMA_XFER_CONT from the device where resources->xferred_dma_size\nis equal to the requested transaction size, the function will return 0\nbefore allocating an sgt or setting the fields of the dma_xfer struct.\nIn that case, encode_addr_size_pairs() will try to access the sgt which\nwill lead to a general protection fault.\n\nReturn an EINVAL in case the user provides a zero-sized ALP, or the device\nrequests continuation after all of the bytes have been transferred." } ], "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 - The bug is reached only via the DRM_IOCTL_QAIC_MANAGE ioctl on the local accel character device /dev/accel/accelN, requiring local system access. There is no network-facing path into qaic_manage_ioctl().\nAC:L - A single ioctl carrying a QAIC_TRANS_DMA_XFER_FROM_USR transaction with the user-controlled size field set to 0 deterministically makes find_and_map_user_pages() return 0 with xfer->sgt/page_list/nr_pages uninitialized; no race and no attacker-independent condition is involved. Grooming the kmalloc-64 slab so the stale sgt is a usable pointer is fully under attacker control via a preceding legitimate DMA xfer.\nPR:L - The QAIC_MANAGE ioctl is registered with flags 0 — no DRM_ROOT_ONLY, no CAP_SYS_ADMIN, and no DRM_AUTH check — so any unprivileged process able to open the accel node (the normal case for inference/compute workloads and containers on AIC100 hosts) can trigger it. No capability is verified anywhere along encode_message() → encode_dma() → find_and_map_user_pages().\nUI:N - The attacker issues the ioctl directly from their own process; no victim action, mount, or file open is needed.\nS:U - The uninitialized-pointer use and resulting corruption occur within the kernel's own security authority, the same authority the attacker escalates into. No VM, IOMMU, or sandbox boundary is crossed as a required part of the impact.\nC:H - Using uninitialized heap memory as a struct sg_table pointer causes reads of arbitrary kernel memory via sgt->nents and the sg walk, and those harvested sg_dma_address/sg_dma_len values are encoded into the message sent to the accelerator, disclosing kernel-controlled DMA addresses off-host to the device. The resulting stale-pointer/double-free state is a general heap corruption primitive leveragable for arbitrary read.\nI:H - free_dma_xfers() unconditionally performs dma_unmap_sgtable(), sg_free_table(), kfree() on the uninitialized sgt and put_page()/kfree() over the uninitialized page_list and nr_pages, yielding arbitrary/double free and page refcount underflow on attacker-groomed pointers. Combined with feeding attacker-influenced addresses to the device's DMA engine, this is exploitable for arbitrary write and control-flow hijack.\nA:H - The commit itself documents that encode_addr_size_pairs() dereferences the unset sgt and produces a general protection fault, i.e. a kernel oops/panic, and it is triggerable repeatedly by any local user with device access. The double-free and page refcount corruption paths cause further fatal kernel faults." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/accel/qaic/qaic_control.c" ], "versions": [ { "version": "96d3c1cadedb6ae2e8965e19cd12caa244afbd9c", "lessThan": "48b1d42286bfef7628b1d6c8c28d4e456c90f725", "status": "affected", "versionType": "git" }, { "version": "96d3c1cadedb6ae2e8965e19cd12caa244afbd9c", "lessThan": "551f1dfbcb7f3e6ed07f9d6c8c1c64337fcd0ede", "status": "affected", "versionType": "git" }, { "version": "96d3c1cadedb6ae2e8965e19cd12caa244afbd9c", "lessThan": "1ab9733d14cc9987cc5dcd1f0ad1f416e302e2e6", "status": "affected", "versionType": "git" }, { "version": "96d3c1cadedb6ae2e8965e19cd12caa244afbd9c", "lessThan": "11f08c30a3e4157305ba692f1d44cca5fc9a8fca", "status": "affected", "versionType": "git" }, { "version": "d410a96e5cb8c1ec7049c83f2edcd8bbfaf5d9b3", "status": "affected", "versionType": "git" }, { "version": "6.4.12", "lessThan": "6.5", "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/accel/qaic/qaic_control.c" ], "versions": [ { "version": "6.5", "status": "affected" }, { "version": "0", "lessThan": "6.5", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.114", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.55", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17.5", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18", "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": "6.5", "versionEndExcluding": "6.6.114" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.12.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.17.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.18" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4.12" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/48b1d42286bfef7628b1d6c8c28d4e456c90f725" }, { "url": "https://git.kernel.org/stable/c/551f1dfbcb7f3e6ed07f9d6c8c1c64337fcd0ede" }, { "url": "https://git.kernel.org/stable/c/1ab9733d14cc9987cc5dcd1f0ad1f416e302e2e6" }, { "url": "https://git.kernel.org/stable/c/11f08c30a3e4157305ba692f1d44cca5fc9a8fca" } ], "title": "accel/qaic: Treat remaining == 0 as error in find_and_map_user_pages()", "x_generator": { "engine": "bippy-1.2.0" } } } }