From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 35B1E355F49; Mon, 27 Apr 2026 16:15:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777306542; cv=none; b=Vur99VucRRt8LmRlbZFtC8Ilk/OR1pminK1S4pogQsZGTp2OZhfi1e+dTFY3wvWFtSZ5rG0GwintnqZCylsQ9EWTKKWb15zfuOvzch+sKYyS14Dncilx+82Wib3615M292g5g5fDYSrrHg1z3cuL8PSkovRO/Zwzs8HuxyxXUkI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777306542; c=relaxed/simple; bh=kFNV6IvwRebNmrJadqN5N4ec/NhPbNyKzVZb/1MxaUo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=h9JY4xikpqgMUwC+cV0UFGxQOX8YkcHr9GqxCosZj9A2NdZW0blmCSxhN7Fq9C1lzCjh8Wli9SYz3Vu2IBZl0MepbptGp+P4BgAyGiU8Kkki8y8YlxqI/Ih41nm3iiADF17UGT4tX2tAQeKqGeTCKo5t4UIrYdHRa1ClDVHqbh4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fxOQLuei; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fxOQLuei" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9593C2BCB5; Mon, 27 Apr 2026 16:15:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777306542; bh=kFNV6IvwRebNmrJadqN5N4ec/NhPbNyKzVZb/1MxaUo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fxOQLuei/EJYGbsbItGRY8LBU+KkHm9/1hfR7UIVDhvIqULQl5Bm0hTUYAObXWfZ3 5LgqxWnVpx7E90wh1Au8JEEpm035YI2koVERz5hdvCF9RLbhm+Zj1ya1tO2QdH/enk 1QAo4TBgyQ0pOrThmDl4uykKsp3+8yi3DZD2OkMD4bB1LJR6FR+WcWZp3BszI5pVWh UjC5Z6BjWc+VgeFBqUFbcq6h8neXyz8+IYoocvEXwdAQUz1vsDk7IefW63l452hp/E fzNRxUiKGM78dd5sqAK1JEcidOiSp7FEH9iNWdGfzm7veRqpHhUPMGLFdBYJpY7VM5 DxafetOOSjeVA== From: Tycho Andersen To: Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" Cc: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Borislav Petkov , "Tycho Andersen (AMD)" Subject: [PATCH v1 2/4] crypto/ccp: Do not initialize SNP for ioctl(SNP_COMMIT) Date: Mon, 27 Apr 2026 10:15:05 -0600 Message-ID: <20260427161507.32686-3-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260427161507.32686-1-tycho@kernel.org> References: <20260427161507.32686-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Tycho Andersen (AMD)" 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 Signed-off-by: Tycho Andersen (AMD) --- drivers/crypto/ccp/sev-dev.c | 13 +------------ 1 file changed, 1 insertion(+), 12 deletions(-) diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 6891b90bbb88..572f06368d4b 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -2437,24 +2437,13 @@ static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp) 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; } -- 2.53.0