From: Tycho Andersen (AMD) Date: Mon, 4 May 2026 16:51:45 +0000 (-0600) Subject: crypto: ccp - Do not initialize SNP for ioctl(SNP_COMMIT) X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=5a1364da2f04217a36e2fdfa2db4ee025b383a20;p=thirdparty%2Flinux.git crypto: ccp - Do not initialize SNP for ioctl(SNP_COMMIT) 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? The SNP_COMMIT command does not require the firmware to be in any particular state. Skip initializing it if it was previously uninitialized. The SEV-SNP firmware specification doc 56860 does not mention SNP_COMMIT in Table 5 as a command that is allowed in the UNINIT state, but it is in fact allowed and a future documentation update will reflect that. Fixes: ceac7fb89e8d ("crypto: ccp - Ensure implicit SEV/SNP init and shutdown in ioctls") Reported-by: Sashiko Assisted-by: Gemini:gemini-3.1-pro-preview Link: https://sashiko.dev/#/patchset/20260324161301.1353976-1-tycho%40kernel.org CC: Signed-off-by: Tycho Andersen (AMD) Reviewed-by: Tom Lendacky Signed-off-by: Herbert Xu --- diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 46c5d7ee7955a..de472f0503cbe 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -2440,24 +2440,13 @@ cleanup: static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp) { - struct sev_device *sev = psp_master->sev_data; struct sev_data_snp_commit buf; - bool shutdown_required = false; - int ret, error; - - if (!sev->snp_initialized) { - ret = snp_move_to_init_state(argp, &shutdown_required); - if (ret) - return ret; - } + int ret; buf.len = sizeof(buf); ret = __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error); - if (shutdown_required) - __sev_snp_shutdown_locked(&error, false); - return ret; }