linux-kernel - Re: [PATCH] objtool: Move objtool

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]

Message-ID: <87mulxxyjq.fsf@gmail.com>
Date:   Thu, 14 Mar 2019 18:31:37 +0300
From:   moosotc@...il.com
To:     Josh Poimboeuf <jpoimboe@...hat.com>
Cc:     x86@...nel.org, linux-kernel@...r.kernel.org,
        Peter Zijlstra <peterz@...radead.org>
Subject: Re: [PATCH] objtool: Move objtool_file struct off the stack

Josh Poimboeuf <jpoimboe@...hat.com> writes:

> Objtool uses over 512k of stack, thanks to the hash table embedded in
> the objtool_file struct.  This causes an unnecessarily large stack
> allocation and breaks users with low stack limits.
>
> Move the struct off the stack.
>
> Fixes: 042ba73fe7eb ("objtool: Add several performance improvements")
> Reported-by: Vassili Karpov <moosotc@...il.com>
> Signed-off-by: Josh Poimboeuf <jpoimboe@...hat.com>
> ---
>  tools/objtool/check.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> index 0414a0d52262..91c4799192e1 100644
> --- a/tools/objtool/check.c
> +++ b/tools/objtool/check.c
> @@ -2184,9 +2184,10 @@ static void cleanup(struct objtool_file *file)
>  	elf_close(file->elf);
>  }
>  
> +struct objtool_file file;
> +

Maybe it also deserves a "static" storage duration (if nothing else this
would prevent possible name clashes)?

>  int check(const char *_objname, bool orc)
>  {
> -	struct objtool_file file;
>  	int ret, warnings = 0;
>  
>  	objname = _objname;

-- 
mailto:moosotc@...il.com