crypto: ccp: Don’t attempt to copy PDH cert to userspace if PSP command failed_CVE-2026-31698

{
    "lastseen": "",
    "description": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp: Don't attempt to copy PDH cert to userspace if PSP command failed\n\nWhen retrieving the PDH cert, don't attempt to copy the blobs to userspace\nif the firmware command failed.  If the failure was due to an invalid\nlength, i.e. the userspace buffer+length was too small, copying the number\nof bytes _firmware_ requires will overflow the kernel-allocated buffer and\nleak data to userspace.\n\n  BUG: KASAN: slab-out-of-bounds in instrument_copy_to_user ../include/linux/instrumented.h:129 [inline]\n  BUG: KASAN: slab-out-of-bounds in _inline_copy_to_user ../include/linux/uaccess.h:205 [inline]\n  BUG: KASAN: slab-out-of-bounds in _copy_to_user+0x66/0xa0 ../lib/usercopy.c:26\n  Read of size 2084 at addr ffff8885c4ab8aa0 by task syz.0.186/21033\n\n  CPU: 51 UID: 0 PID: 21033 Comm: syz.0.186 Tainted: G     U     O        7.0.0-smp-DEV #28 PREEMPTLAZY\n  Tainted: [U]=USER, [O]=OOT_MODULE\n  Hardware name: Google, Inc.                                                       Arcadia_IT_80/Arcadia_IT_80, BIOS 34.84.12-0 11/17/2025\n  Call Trace:\n   <TASK>\n   dump_stack_lvl+0xc5/0x110 ../lib/dump_stack.c:120\n   print_address_description ../mm/kasan/report.c:378 [inline]\n   print_report+0xbc/0x260 ../mm/kasan/report.c:482\n   kasan_report+0xa2/0xe0 ../mm/kasan/report.c:595\n   check_region_inline ../mm/kasan/generic.c:-1 [inline]\n   kasan_check_range+0x264/0x2c0 ../mm/kasan/generic.c:200\n   instrument_copy_to_user ../include/linux/instrumented.h:129 [inline]\n   _inline_copy_to_user ../include/linux/uaccess.h:205 [inline]\n   _copy_to_user+0x66/0xa0 ../lib/usercopy.c:26\n   copy_to_user ../include/linux/uaccess.h:236 [inline]\n   sev_ioctl_do_pdh_export+0x3d3/0x7c0 ../drivers/crypto/ccp/sev-dev.c:2347\n   sev_ioctl+0x2a2/0x490 ../drivers/crypto/ccp/sev-dev.c:2568\n   vfs_ioctl ../fs/ioctl.c:51 [inline]\n   __do_sys_ioctl ../fs/ioctl.c:597 [inline]\n   __se_sys_ioctl+0x11d/0x1b0 ../fs/ioctl.c:583\n   do_syscall_x64 ../arch/x86/entry/syscall_64.c:63 [inline]\n   do_syscall_64+0xe0/0x800 ../arch/x86/entry/syscall_64.c:94\n   entry_SYSCALL_64_after_hwframe+0x76/0x7e\n   </TASK>\n\nWARN if the driver says the command succeeded, but the firmware error code\nsays otherwise, as __sev_do_cmd_locked() is expected to return -EIO on any\nfirwmware error.",
    "published": "2026-05-01T13:55:58.854Z",
    "modified": "2026-05-03T05:45:23.344Z",
    "type": "cve",
    "title": "crypto: ccp: Don't attempt to copy PDH cert to userspace if PSP command failed",
    "source": "Linux",
    "references": "https://git.kernel.org/stable/c/b5c14bd4da1f376f385722fe1da993f1edab6472\nhttps://git.kernel.org/stable/c/78b97e43d0b3e674d9d49ae56937b11e2ba3fcaf\nhttps://git.kernel.org/stable/c/051e51aa55fd4cdc3e8283cf4476aeeb5f563274\nhttps://git.kernel.org/stable/c/50808c13452dae43a2c90b1bbbf9daa16501ce70\nhttps://git.kernel.org/stable/c/e76239fed3cffd6d304d8ca3ce23984fd24f57d3",
    "id": "CVE-2026-31698",
    "bulletinFamily": "",
    "cwe": null,
    "cvelist": null,
    "sourceData": "Linux Linux 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436\nLinux Linux 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436\nLinux Linux 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436\nLinux Linux 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436\nLinux Linux 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436\nLinux Linux 4.16",
    "sourceHref": "",
    "cvss": {
        "score": 7.1,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
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        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
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        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
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            "baseScore": 0,
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            "privilegesRequired": "",
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            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Linux",
    "version": "76a2b524a4b1d6dc0f2421f9854a01d55d5e5436",
    "vendor": "Linux",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
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    "ai_score": 0
}