linux-kernel - Re: [PATCH 5/9] x86/dumpstack: Improve opcodes dumping in the Code: section

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]

Date:   Thu, 8 Mar 2018 10:00:09 -0800
From:   Linus Torvalds <torvalds@...ux-foundation.org>
To:     Borislav Petkov <bp@...en8.de>
Cc:     Josh Poimboeuf <jpoimboe@...hat.com>, X86 ML <x86@...nel.org>,
        Andy Lutomirski <luto@...capital.net>,
        Peter Zijlstra <peterz@...radead.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 5/9] x86/dumpstack: Improve opcodes dumping in the Code: section

On Thu, Mar 8, 2018 at 2:16 AM, Borislav Petkov <bp@...en8.de> wrote:
> +#define OPCODE_BUFSIZE 64
> +       unsigned int code_prologue = OPCODE_BUFSIZE * 43 / OPCODE_BUFSIZE;

Heh.

That's a very odd way of writing "43".

Honestly, the "43" is just "two thirds" rounded to closest, and it's
not important anyway, so I think you should just write it as

        unsigned int code_prologue = OPCODE_BUFSIZE * 2 / 3;

and never mind that it will now be 42.

42 is obviously the right answer anyway, which makes me think we got
it wrong earlier.

         Linus