diff mbox series

[06/10] x86/tdx: Mark message.str as nonstring

Message ID 20250207010022.749952-6-kees@kernel.org
State New
Headers show
Series Annotate arguments of memtostr/strtomem with __nonstring | expand

Commit Message

Kees Cook Feb. 7, 2025, 1 a.m. UTC
In preparation for strtomem*() checking that its destination is a
nonstring, annotate message.str accordingly.

Signed-off-by: Kees Cook <kees@kernel.org>
---
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-coco@lists.linux.dev
---
 arch/x86/coco/tdx/tdx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Kirill A. Shutemov Feb. 10, 2025, 11:53 a.m. UTC | #1
On Thu, Feb 06, 2025 at 06:37:27PM -0800, Kees Cook wrote:
> On Thu, Feb 06, 2025 at 05:12:11PM -0800, Dave Hansen wrote:
> > On 2/6/25 17:00, Kees Cook wrote:
> > > +++ b/arch/x86/coco/tdx/tdx.c
> > > @@ -170,7 +170,7 @@ static void __noreturn tdx_panic(const char *msg)
> > >  		/* Define register order according to the GHCI */
> > >  		struct { u64 r14, r15, rbx, rdi, rsi, r8, r9, rdx; };
> > >  
> > > -		char str[64];
> > > +		char str[64] __nonstring;
> > >  	} message;
> > 
> > So, the patch itself makes sense. But it does end up looking kinda
> > funky. We call it a "str"ing and then annotate it as not a string.
> 
> Yeah, this is true all over the place. It's a string, just not a
> NUL-terminated string: *sob*
> 
> > It doesn't have to be done in this patch, but it does seem like we
> > should probably not be using 'char' and also shouldn't call it anything
> > close to "string". Maybe:
> > 
> >	 	u8 message[64] __nonstring;
> > 	} message;
> 
> message.message ;)
> 
> message.chars?
> message.bytes?

.bytes sounds good to me.

Anyway:

Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
diff mbox series

Patch

diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c
index 0d9b090b4880..977ab1ffa3fe 100644
--- a/arch/x86/coco/tdx/tdx.c
+++ b/arch/x86/coco/tdx/tdx.c
@@ -170,7 +170,7 @@  static void __noreturn tdx_panic(const char *msg)
 		/* Define register order according to the GHCI */
 		struct { u64 r14, r15, rbx, rdi, rsi, r8, r9, rdx; };
 
-		char str[64];
+		char str[64] __nonstring;
 	} message;
 
 	/* VMM assumes '\0' in byte 65, if the message took all 64 bytes */