From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f74.google.com (mail-pj1-f74.google.com [209.85.216.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 346E233555E for ; Thu, 30 Oct 2025 20:10:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761855057; cv=none; b=IV5EXLVtqBxjEjAaZ+adp5VHULk77PS38q5yq0YpAqKvx/FLK/5U6Hqgu5HxLOBKg9K3TXvA5JoKDqyDnoRLRZyuJ0MOlElUAtPMgScctEkysPK/zIrlunICAGIJ8Q+RfjQlke/N3nDZH2k6BWH1P22nRX4kIVdjkpU/0Q8Wfks= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761855057; c=relaxed/simple; bh=ijmVL6tuMasvfCu8NJ2oY2dmKaMYxvGjS6YgS4whU3k=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=SlA2ctPoeVxzdR6aFtSy5eM6GRTtqUO2uMftTralrCTp0GNzYy42pa6snNMbKNCuL+kIA0ZeCaYDyIkqPCjFZhhRHa0xEEA5Ec0hDwwkWVDKe714z0hFn+ZGdkwfDUZ2chNSOy9g0iq2N9Q8UwEIJzsR29mcnhLygfzYHrZyRho= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=n2vPQknC; arc=none smtp.client-ip=209.85.216.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="n2vPQknC" Received: by mail-pj1-f74.google.com with SMTP id 98e67ed59e1d1-33bbbb41a84so3170937a91.1 for ; Thu, 30 Oct 2025 13:10:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1761855055; x=1762459855; darn=lists.linux.dev; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=HfwppzbkJFTqc1oDUhl9YAWd2H/Ydo3ViOcPjYsyqPw=; b=n2vPQknCvUURdE3XRczIVhaD+1pmQZSUoxeC/b494onZ5X5KKLCsH1j7B5Jme6IG2c MBRweuyaVqDriCQIV+DWfqheucdsi8nId6lX8Y3fIWSo92Zt5U1mSItCUogZM3MaI1ts N9q3wBgrEP5PUVip0AchdcppOpcBMeluthVbAIEMmL7htyDWWWKzQ2zraE8aZse48UAf TEjL71PgEXi9Nw1jKeZjMOMKZGYoFY27QBm0OLNYztkFR8c1jIZH95dF2iKX4mCmBRY8 1RuDmAZG2kyVmBlQpRg6XbE1QJCpoP/wBhUsZqKxRSHT61TLHvsLWmnSQFJMNdvpndev Smzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761855055; x=1762459855; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=HfwppzbkJFTqc1oDUhl9YAWd2H/Ydo3ViOcPjYsyqPw=; b=ozcGq2j+NN8mVf3KRBMWIuyV24knpVO52e0S0KRWxmhooZCg/YZo6He8Pl6LhlryAu 6ZyctM+CAackGmKRfwzuJSIlRr+m1S1pDFhgYIuxZyRQJzSyCbUlzO05c6FviszzkyjK P42eQi0rDH708AM9BPtc4jEi0Bi6W+1hyLEnxSj6doGdz/dX2tq+U7VK8KdHoCXz8ecg vT21iDWZ5aIWhV5e0Gn6arA2e/AqdksgBi2Cok+Qg8nAQELwep/oTu3TI3Zyo6ZPQepQ lJxrGEcX8plINp+A+COWnRupyzletRcX7cN29563jCG3V5U3q7Gced4CyWH1y8QGAwOl wReg== X-Forwarded-Encrypted: i=1; AJvYcCX/G4FNQ4PETu3YOYr2Nj35nau2mHvWh9K3dPqnWppPk+Ip7doa44x7+8LmRY9IhabvyWgyX08=@lists.linux.dev X-Gm-Message-State: AOJu0YzkNCq0AsjQvnf8mZZhHfFUXrEjRl6ks9FmskQcRop9IGqEZh2X 7murijFWYeNcJB1VBK3f9Et2rw8X/Izt83b8yy+gWgrLn12oY/NevNL3Mj2e4YVYEiBdlTgj7j1 Y/ejyVw== X-Google-Smtp-Source: AGHT+IFgv0+NgL48Cma0Y79QUzd7lRP+/FCxQ0tZkUpinDRTeLAklkWHALMXu+tHUB2W7Y9sxKQZz0IMk4g= X-Received: from pjbbt9.prod.google.com ([2002:a17:90a:f009:b0:340:7770:2e30]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:1f82:b0:32e:a5ae:d00 with SMTP id 98e67ed59e1d1-34082fc7b43mr1201499a91.13.1761855054620; Thu, 30 Oct 2025 13:10:54 -0700 (PDT) Reply-To: Sean Christopherson Date: Thu, 30 Oct 2025 13:09:45 -0700 In-Reply-To: <20251030200951.3402865-1-seanjc@google.com> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251030200951.3402865-1-seanjc@google.com> X-Mailer: git-send-email 2.51.1.930.gacf6e81ea2-goog Message-ID: <20251030200951.3402865-23-seanjc@google.com> Subject: [PATCH v4 22/28] KVM: TDX: Add tdx_get_cmd() helper to get and validate sub-ioctl command From: Sean Christopherson To: Marc Zyngier , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Madhavan Srinivasan , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Sean Christopherson , Paolo Bonzini , "Kirill A. Shutemov" Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, x86@kernel.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, Ira Weiny , Kai Huang , Binbin Wu , Michael Roth , Yan Zhao , Vishal Annapurve , Rick Edgecombe , Ackerley Tng Content-Type: text/plain; charset="UTF-8" Add a helper to copy a kvm_tdx_cmd structure from userspace and verify that must-be-zero fields are indeed zero. No functional change intended. Reviewed-by: Rick Edgecombe Reviewed-by: Kai Huang Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/tdx.c | 35 +++++++++++++++++++++-------------- 1 file changed, 21 insertions(+), 14 deletions(-) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 97632fc6b520..390c934562c1 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -2782,20 +2782,29 @@ static int tdx_td_finalize(struct kvm *kvm, struct kvm_tdx_cmd *cmd) return 0; } +static int tdx_get_cmd(void __user *argp, struct kvm_tdx_cmd *cmd) +{ + if (copy_from_user(cmd, argp, sizeof(*cmd))) + return -EFAULT; + + /* + * Userspace should never set hw_error. KVM writes hw_error to report + * hardware-defined error back to userspace. + */ + if (cmd->hw_error) + return -EINVAL; + + return 0; +} + int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { struct kvm_tdx_cmd tdx_cmd; int r; - if (copy_from_user(&tdx_cmd, argp, sizeof(struct kvm_tdx_cmd))) - return -EFAULT; - - /* - * Userspace should never set hw_error. It is used to fill - * hardware-defined error by the kernel. - */ - if (tdx_cmd.hw_error) - return -EINVAL; + r = tdx_get_cmd(argp, &tdx_cmd); + if (r) + return r; mutex_lock(&kvm->lock); @@ -3171,11 +3180,9 @@ int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) if (!is_hkid_assigned(kvm_tdx) || kvm_tdx->state == TD_STATE_RUNNABLE) return -EINVAL; - if (copy_from_user(&cmd, argp, sizeof(cmd))) - return -EFAULT; - - if (cmd.hw_error) - return -EINVAL; + ret = tdx_get_cmd(argp, &cmd); + if (ret) + return ret; switch (cmd.id) { case KVM_TDX_INIT_VCPU: -- 2.51.1.930.gacf6e81ea2-goog