[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20170207173036.GS6515@twins.programming.kicks-ass.net>
Date: Tue, 7 Feb 2017 18:30:36 +0100
From: Peter Zijlstra <peterz@...radead.org>
To: Mark Rutland <mark.rutland@....com>
Cc: Kees Cook <keescook@...omium.org>,
"Reshetova, Elena" <elena.reshetova@...el.com>,
Greg KH <gregkh@...uxfoundation.org>, Arnd Bergmann <arnd@...db.de>,
Thomas Gleixner <tglx@...utronix.de>,
Ingo Molnar <mingo@...nel.org>,
"H. Peter Anvin" <h.peter.anvin@...el.com>,
Will Deacon <will.deacon@....com>,
David Windsor <dwindsor@...il.com>,
Hans Liljestrand <ishkamiel@...il.com>,
David Howells <dhowells@...hat.com>,
LKML <linux-kernel@...r.kernel.org>,
"kernel-hardening@...ts.openwall.com" <kernel-hardening@...ts.openwall.com>
Subject: Re: Re: [PATCH 4/4] refcount: Report failures
through CHECK_DATA_CORRUPTION
On Tue, Feb 07, 2017 at 04:03:01PM +0000, Mark Rutland wrote:
> For x86 it's a little painful due to '%' in the register names, but it looks
> possible. The below appears to do the mangling correctly (then screams due to
> the mangled result being nonexistent).
> asm(
> " .macro reg_to_offset r\n"
> " .irp rs,eax,ebx,ecx,edx\n"
> " .ifc \\r, %\\rs\n"
> " __offset_of_\\rs\n"
> " .endif\n"
> " .endr\n"
> " .endm\n"
> );
>
> #define asm_sym(var) asm volatile("reg_to_offset %0\n" : : "r" (var))
Oh gawd that's a most gnarly hack.
Do we want to go do that for all archs or somehow cook a generic
fallback that ends up doing a full function call or something?
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
