linux-kernel - Re: [PATCH v2 12/39] x86/ibt,ftrace: Search for __fentry_

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, 24 Feb 2022 17:51:41 -0500
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Josh Poimboeuf <jpoimboe@...hat.com>
Cc:     Masami Hiramatsu <mhiramat@...nel.org>,
        Peter Zijlstra <peterz@...radead.org>, x86@...nel.org,
        joao@...rdrivepizza.com, hjl.tools@...il.com,
        andrew.cooper3@...rix.com, linux-kernel@...r.kernel.org,
        ndesaulniers@...gle.com, keescook@...omium.org,
        samitolvanen@...gle.com, mark.rutland@....com,
        alyssa.milburn@...el.com, mbenes@...e.cz,
        alexei.starovoitov@...il.com
Subject: Re: [PATCH v2 12/39] x86/ibt,ftrace: Search for __fentry__ location

On Thu, 24 Feb 2022 14:46:31 -0800
Josh Poimboeuf <jpoimboe@...hat.com> wrote:

> > > > > +			rec = lookup_rec(ip - offset, (ip - offset) + size);  
> 
> If 'offset' is zero then why the math here?      ^^^^^^^^^^^   ^^^^^^^^^^^

Because it didn't check for offset being zero when we wrote that line. ;-)

Yes, checking for !offset makes that logic irrelevant.

Good catch.

-- Steve