{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-38658", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:24.031Z", "datePublished": "2025-08-22T16:01:01.651Z", "dateUpdated": "2026-08-05T12:03:45.053Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:03:45.053Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvmet: pci-epf: Do not complete commands twice if nvmet_req_init() fails\n\nHave nvmet_req_init() and req->execute() complete failed commands.\n\nDescription of the problem:\nnvmet_req_init() calls __nvmet_req_complete() internally upon failure,\ne.g., unsupported opcode, which calls the \"queue_response\" callback,\nthis results in nvmet_pci_epf_queue_response() being called, which will\ncall nvmet_pci_epf_complete_iod() if data_len is 0 or if dma_dir is\ndifferent from DMA_TO_DEVICE. This results in a double completion as\nnvmet_pci_epf_exec_iod_work() also calls nvmet_pci_epf_complete_iod()\nwhen nvmet_req_init() fails.\n\nSteps to reproduce:\nOn the host send a command with an unsupported opcode with nvme-cli,\nFor example the admin command \"security receive\"\n$ sudo nvme security-recv /dev/nvme0n1 -n1 -x4096\n\nThis triggers a double completion as nvmet_req_init() fails and\nnvmet_pci_epf_queue_response() is called, here iod->dma_dir is still\nin the default state of \"DMA_NONE\" as set by default in\nnvmet_pci_epf_alloc_iod(), so nvmet_pci_epf_complete_iod() is called.\nBecause nvmet_req_init() failed nvmet_pci_epf_complete_iod() is also\ncalled in nvmet_pci_epf_exec_iod_work() leading to a double completion.\nThis not only sends two completions to the host but also corrupts the\nstate of the PCI NVMe target leading to kernel oops.\n\nThis patch lets nvmet_req_init() and req->execute() complete all failed\ncommands, and removes the double completion case in\nnvmet_pci_epf_exec_iod_work() therefore fixing the edge cases where\ndouble completions occurred." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:A - The vulnerable code is the NVMe PCI *endpoint* target, driven entirely by NVMe commands submitted by a separate root-complex host across the PCIe link, so the attacker is external software on a directly-attached peer machine rather than a user of the endpoint system. In the deployments this driver targets (disaggregated/composable PCIe storage, and endpoint devices VFIO-passed-through to untrusted guests) no physical manipulation is needed at attack time — only presence on the same logically adjacent PCIe fabric.\nAC:L - A single NVMe command with an opcode the target does not implement deterministically fails nvmet_req_init() and produces the double completion; the commit itself gives a one-line nvme-cli reproducer. No timing, memory-layout, or victim-state condition outside the attacker's control is involved.\nPR:N - NVMe over PCIe has no authentication or authorization step — the host merely enables CC.EN, creates queues, and writes a doorbell — so the attacker holds no credentials at all on the vulnerable endpoint system. Any command submitter on the attached host or a passed-through guest reaches the failing path.\nUI:N - The endpoint's SQ-polling work item picks up the malformed command and dispatches it automatically. No action by any user or administrator on the victim endpoint system is required.\nS:U - The corruption is confined to the endpoint kernel's own heap and driver state, the same security authority that contains the vulnerable code. The cross-machine nature of the attack is already captured by the Attack Vector metric.\nC:H - The dangling CQ list entry causes nvmet_pci_epf_cq_work() to re-read a freed iod and build a completion entry from it (including a dereference of a possibly reallocated iod->sq), which is memcpy_toio()'d straight into the attacker host's completion queue, leaking reused kernel heap contents. More broadly, the double free and iod aliasing yield general heap-corruption primitives leverageable for arbitrary kernel memory disclosure.\nI:H - The same iod is returned to the mempool twice, so two concurrent commands are handed the identical object and its data_segs buffers are kfree()'d twice in shared kmalloc caches, with the attacker controlling those buffers' sizes and contents via PRP/SGL lists and DMA. A double free plus use-after-free write on an aliased object is a well-established path to controlled kernel writes and control-flow hijack.\nA:H - The commit explicitly states the double completion \"corrupts the state of the PCI NVMe target leading to kernel oops,\" and CONFIG_DEBUG_LIST additionally trips on the duplicate list_add. The attacker can repeat the triggering command at will to panic or wedge the endpoint system." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/nvme/target/pci-epf.c" ], "versions": [ { "version": "0faa0fe6f90ea59b10d1b0f15ce0eb0c18eff186", "lessThan": "a535c0b10060bc8c174a7964b0f98064ee0c4774", "status": "affected", "versionType": "git" }, { "version": "0faa0fe6f90ea59b10d1b0f15ce0eb0c18eff186", "lessThan": "746d0ac5a07d5da952ef258dd4d75f0b26c96476", "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/nvme/target/pci-epf.c" ], "versions": [ { "version": "6.14", "status": "affected" }, { "version": "0", "lessThan": "6.14", "status": "unaffected", "versionType": "semver" }, { "version": "6.16.1", "lessThanOrEqual": "6.16.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17", "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": "6.14", "versionEndExcluding": "6.16.1" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "6.17" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/a535c0b10060bc8c174a7964b0f98064ee0c4774" }, { "url": "https://git.kernel.org/stable/c/746d0ac5a07d5da952ef258dd4d75f0b26c96476" } ], "title": "nvmet: pci-epf: Do not complete commands twice if nvmet_req_init() fails", "x_generator": { "engine": "bippy-1.2.0" } } } }