crypto: acomp – fix wrong pointer stored by acomp_save_req()_CVE-2026-46081

{
    "lastseen": "",
    "description": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: acomp - fix wrong pointer stored by acomp_save_req()\n\nacomp_save_req() stores &req->chain in req->base.data. When\nacomp_reqchain_done() is invoked on asynchronous completion, it receives\n&req->chain as the data argument but casts it directly to struct\nacomp_req. Since data points to the chain member, all subsequent field\naccesses are at a wrong offset, resulting in memory corruption.\n\nThe issue occurs when an asynchronous hardware implementation, such as\nthe QAT driver, completes a request that uses the DMA virtual address\ninterface (e.g. acomp_request_set_src_dma()). This combination causes\ncrypto_acomp_compress() to enter the acomp_do_req_chain() path, which\nsets acomp_reqchain_done() as the completion callback via\nacomp_save_req().\n\nWith KASAN enabled, this manifests as a general protection fault in\nacomp_reqchain_done():\n\n  general protection fault, probably for non-canonical address 0xe000040000000000\n  KASAN: probably user-memory-access in range [0x0000400000000000-0x0000400000000007]\n  RIP: 0010:acomp_reqchain_done+0x15b/0x4e0\n  Call Trace:\n   <IRQ>\n   qat_comp_alg_callback+0x5d/0xa0 [intel_qat]\n   adf_ring_response_handler+0x376/0x8b0 [intel_qat]\n   adf_response_handler+0x60/0x170 [intel_qat]\n   tasklet_action_common+0x223/0x820\n   handle_softirqs+0x1ab/0x640\n   </IRQ>\n\nFix this by storing the request itself in req->base.data instead of\n&req->chain, so that acomp_reqchain_done() receives the correct pointer.\nSimplify acomp_restore_req() accordingly to access req->chain directly.",
    "published": "2026-05-27T12:58:19.498Z",
    "modified": "2026-05-30T10:47:20.873Z",
    "type": "cve",
    "title": "crypto: acomp - fix wrong pointer stored by acomp_save_req()",
    "source": "Linux",
    "references": "https://git.kernel.org/stable/c/343a5bf68a8ff9affcf2b70677ea4cf40c195ee4\nhttps://git.kernel.org/stable/c/1a2785e5985627f2265ba7775949601a29ba0d1e\nhttps://git.kernel.org/stable/c/d7e20b9bd6c990773cf0c09e2642250b8a70263d",
    "id": "CVE-2026-46081",
    "bulletinFamily": "",
    "cwe": null,
    "cvelist": null,
    "sourceData": "Linux Linux 64929fe8c0a43508eee952cf57903a61c52601e7\nLinux Linux 64929fe8c0a43508eee952cf57903a61c52601e7\nLinux Linux 64929fe8c0a43508eee952cf57903a61c52601e7\nLinux Linux 6.16",
    "sourceHref": "",
    "cvss": {
        "score": 7.8,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Linux",
    "version": "64929fe8c0a43508eee952cf57903a61c52601e7",
    "vendor": "Linux",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
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    "ai_score": 0
}