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Date: Mon, 23 May 2016 17:33:55 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Michal Hocko <mhocko@kernel.org>
Cc: Aleksa Sarai <asarai@suse.de>, LKML <linux-kernel@vger.kernel.org>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>,
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        Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org
Subject: Re: [PATCH] x86: fix potential memleak in do_error_trap
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On 05/23, Michal Hocko wrote:
>
> @@ -271,6 +271,7 @@ static void do_error_trap(struct pt_regs *regs, long error_code, char *str,
>
>  	if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) !=
>  			NOTIFY_STOP) {
> +		memset(&info, 0, sizeof(info));
>  		cond_local_irq_enable(regs);
>  		do_trap(trapnr, signr, str, regs, error_code,
>  			fill_trap_info(regs, signr, trapnr, &info));

at first glance fill_trap_info() initializes everything we will copy
to user-space in copy_siginfo_to_user(__SI_FAULT).

But even if not, shuldn't we change fill_trap_info() instead ?

Oleg.