linux-kernel - Re: [PATCH][v3] virt: tdx-guest: Don't free decrypted 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] [day] [month] [year] [list]

Message-ID: <uggd72vugduczhkifii57aflkv4hxsija5iwyqvxdr24tbysus@nq4xx7putbxg>
Date: Wed, 19 Jun 2024 13:37:48 +0300
From: "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
To: Li RongQing <lirongqing@...du.com>
Cc: dave.hansen@...ux.intel.com, x86@...nel.org, 
	linux-coco@...ts.linux.dev, linux-kernel@...r.kernel.org, rick.p.edgecombe@...el.com
Subject: Re: [PATCH][v3] virt: tdx-guest: Don't free decrypted memory

On Wed, Jun 19, 2024 at 04:47:50PM +0800, Li RongQing wrote:
> In CoCo VMs it is possible for the untrusted host to cause
> set_memory_decrypted() to fail such that an error is returned
> and the resulting memory is shared. Callers need to take care
> to handle these errors to avoid returning decrypted (shared)
> memory to the page allocator, which could lead to functional
> or security issues. So leak the decrypted memory when
> set_memory_decrypted fails, and don't need to print an error
> since set_memory_decrypted will call WARN_ONCE.

Add "()" for set_memory_decrypted() and WARN_ONCE().

And put the solution into a separate paragraph:

s/ So leak/\n\nLeak/

> Reviewed-by: Rick Edgecombe <rick.p.edgecombe@...el.com>
> Signed-off-by: Li RongQing <lirongqing@...du.com>

Otherwise, looks good:

Reviewed-by: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com>

-- 
  Kiryl Shutsemau / Kirill A. Shutemov