linux-kernel - Re: [PATCH 19/21] KVM: TDX: Add an ioctl to create initial guest memory

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <85754805bef1cdbe6079ab549935fee4ec310a62.camel@intel.com>
Date: Wed, 4 Sep 2024 13:56:20 +0000
From: "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
To: "kvm@...r.kernel.org" <kvm@...r.kernel.org>, "pbonzini@...hat.com"
	<pbonzini@...hat.com>, "seanjc@...gle.com" <seanjc@...gle.com>
CC: "Zhao, Yan Y" <yan.y.zhao@...el.com>, "nik.borisov@...e.com"
	<nik.borisov@...e.com>, "dmatlack@...gle.com" <dmatlack@...gle.com>, "Huang,
 Kai" <kai.huang@...el.com>, "isaku.yamahata@...il.com"
	<isaku.yamahata@...il.com>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 19/21] KVM: TDX: Add an ioctl to create initial guest
 memory

On Tue, 2024-09-03 at 20:07 -0700, Rick Edgecombe wrote:
> +static int tdx_gmem_post_populate(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn,
> +                                 void __user *src, int order, void *_arg)
> +{
> +       u64 error_code = PFERR_GUEST_FINAL_MASK | PFERR_PRIVATE_ACCESS;
> +       struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> +       struct tdx_gmem_post_populate_arg *arg = _arg;
> +       struct kvm_vcpu *vcpu = arg->vcpu;
> +       gpa_t gpa = gfn_to_gpa(gfn);
> +       u8 level = PG_LEVEL_4K;
> +       struct page *page;
> +       int ret, i;
> +       u64 err, entry, level_state;
> +
> +       /*
> +        * Get the source page if it has been faulted in. Return failure if
> the
> +        * source page has been swapped out or unmapped in primary memory.
> +        */
> +       ret = get_user_pages_fast((unsigned long)src, 1, 0, &page);
> +       if (ret < 0)
> +               return ret;
> +       if (ret != 1)
> +               return -ENOMEM;
> +
> +       if (!kvm_mem_is_private(kvm, gfn)) {
> +               ret = -EFAULT;
> +               goto out_put_page;
> +       }

Paulo had said he was going to add this check in gmem code. I thought it was not
added but it actually is. So we can drop this check.