linux-kernel - Re: [PATCH] getrusage: fill ru

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] [day] [month] [year] [list]

Message-ID: <20081124180031.GA20155@redhat.com>
Date:	Mon, 24 Nov 2008 19:00:31 +0100
From:	Oleg Nesterov <oleg@...hat.com>
To:	Jiri Pirko <jpirko@...hat.com>
Cc:	linux-kernel@...r.kernel.org,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [PATCH] getrusage: fill ru_maxrss value

On 11/24, Jiri Pirko wrote:
>
> @@ -1588,6 +1589,13 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
>  				accumulate_thread_rusage(t, r);
>  				t = next_thread(t);
>  			} while (t != p);
> +			if (p->mm) {
> +				update_hiwater_rss(p->mm);
> +				if (r->ru_maxrss < p->mm->hiwater_rss)
> +					r->ru_maxrss = p->mm->hiwater_rss;

The task can free its ->mm right after the check. You need get_task_mm(),
but you can't do this under ->siglock because it takes task_lock().

I think you can move this code outside of lock_task_sighand().

Oleg.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/