GHSA-CFM2-F7PX-WG9F
Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-25 12:31In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Do not initialize SNP for SEV ioctls
Sashiko notes:
if SEV initialization fails and KVM is actively running normal VMs, could a userspace process trigger this code path via /dev/sev ioctls (e.g., SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN execution for an active VM trigger a general protection fault and crash the host?
sev_move_to_init_state() is called for ioctls requiring only SEV firmware: SEV_PEK_GEN, SEV_PDH_GEN, SEV_PEK_CSR, SEV_PEK_CERT_IMPORT, and SEV_PDH_CERT_EXPORT. After the firmware command, it does SEV_SHUTDOWN on the SEV firmware. Since these commands do not require SNP to be initialized, skip it by calling __sev_platform_init_locked() which only initializes the SEV firmware. This way SNP is not Initialized at all, and HSAVE_PA is not cleared.
The previous code saved any SEV initialization firmware error to init_args.error and then threw it away and hardcoded the return value of INVALID_PLATFORM_STATE regardless of the real firmware error. This patch changes it to surface the underlying error, which is hopefully both more useful and doesn't cause any problems.
Note that it is still safe to call __sev_firmware_shutdown() directly: it calls __sev_snp_shutdown_locked(), which skips SNP shutdown if SNP was not initialized.
{
"affected": [],
"aliases": [
"CVE-2026-64310"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-25T10:17:12Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp - Do not initialize SNP for SEV ioctls\n\nSashiko notes:\n\n\u003e if SEV initialization fails and KVM is actively running normal VMs, could a\n\u003e userspace process trigger this code path via /dev/sev ioctls (e.g.,\n\u003e SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN\n\u003e execution for an active VM trigger a general protection fault and crash the\n\u003e host?\n\nsev_move_to_init_state() is called for ioctls requiring only SEV firmware:\nSEV_PEK_GEN, SEV_PDH_GEN, SEV_PEK_CSR, SEV_PEK_CERT_IMPORT, and\nSEV_PDH_CERT_EXPORT. After the firmware command, it does SEV_SHUTDOWN on\nthe SEV firmware. Since these commands do not require SNP to be\ninitialized, skip it by calling __sev_platform_init_locked() which only\ninitializes the SEV firmware. This way SNP is not Initialized at all, and\nHSAVE_PA is not cleared.\n\nThe previous code saved any SEV initialization firmware error to\ninit_args.error and then threw it away and hardcoded the return value of\nINVALID_PLATFORM_STATE regardless of the real firmware error. This patch\nchanges it to surface the underlying error, which is hopefully both more\nuseful and doesn\u0027t cause any problems.\n\nNote that it is still safe to call __sev_firmware_shutdown() directly: it\ncalls __sev_snp_shutdown_locked(), which skips SNP shutdown if SNP was not\ninitialized.",
"id": "GHSA-cfm2-f7px-wg9f",
"modified": "2026-07-25T12:31:30Z",
"published": "2026-07-25T12:31:30Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64310"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5181e88da99c3d1d41e25db3472a62b8d4b42cdd"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9e983d0a74a6a2348e4ce61647ec8a4dfbe198ac"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d51207735e7c224cf591fa260c557a451a69a5cf"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fb1758e74b8061aacfbce7bbb7a7cc650537e167"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
|---|
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