linux-kernel - Re: [PATCH 10/14] x86/unwind/orc: Prevent unwinding before ORC initialization

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: <alpine.LSU.2.21.2003131321340.30076@pobox.suse.cz>
Date:   Fri, 13 Mar 2020 13:24:09 +0100 (CET)
From:   Miroslav Benes <mbenes@...e.cz>
To:     Josh Poimboeuf <jpoimboe@...hat.com>
cc:     x86@...nel.org, linux-kernel@...r.kernel.org,
        Peter Zijlstra <peterz@...radead.org>,
        Vince Weaver <vincent.weaver@...ne.edu>,
        Dave Jones <dsj@...com>, Jann Horn <jannh@...gle.com>,
        Andy Lutomirski <luto@...nel.org>,
        Steven Rostedt <rostedt@...dmis.org>,
        Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH 10/14] x86/unwind/orc: Prevent unwinding before ORC
 initialization

On Thu, 12 Mar 2020, Josh Poimboeuf wrote:

> If the unwinder is called before the ORC data has been initialized,
> orc_find() returns NULL, and it tries to fall back to using frame
> pointers.  This can cause some unexpected warnings during boot.
> 
> Move the 'orc_init' check from orc_find() to __unwind_init(), so that it

s/__unwind_init()/__unwind_start()/

>  void __unwind_start(struct unwind_state *state, struct task_struct *task,
>  		    struct pt_regs *regs, unsigned long *first_frame)
>  {
> +	if (!orc_init)
> +		goto done;
> +
>  	memset(state, 0, sizeof(*state));
>  	state->task = task;

Miroslav