From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756762Ab1EFTde (ORCPT ); Fri, 6 May 2011 15:33:34 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:50156 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750779Ab1EFTdd (ORCPT ); Fri, 6 May 2011 15:33:33 -0400 Date: Fri, 6 May 2011 12:33:28 -0700 From: Andrew Morton To: Tetsuo Handa Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, John Stultz Subject: Re: [PATCH 1/1] coredump: use task comm instead of (unknown) Message-Id: <20110506123328.d0a707b7.akpm@linux-foundation.org> In-Reply-To: <201105062126.DIE34311.OJHtFMFFSQLVOO@I-love.SAKURA.ne.jp> References: <4DC0FFAB.1000805@gmail.com> <1304494354-21487-1-git-send-email-jslaby@suse.cz> <20110505150601.a4457970.akpm@linux-foundation.org> <201105062126.DIE34311.OJHtFMFFSQLVOO@I-love.SAKURA.ne.jp> X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.1; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (Cc John) On Fri, 6 May 2011 21:26:39 +0900 Tetsuo Handa wrote: > Andrew Morton wrote: > > Direct access to current->comm is racy since we added > > prctl(PR_SET_NAME). > > A passer-by's question. Did we change below one > > char *get_task_comm(char *buf, struct task_struct *tsk) > { > /* buf must be at least sizeof(tsk->comm) in size */ > task_lock(tsk); > strncpy(buf, tsk->comm, sizeof(tsk->comm)); > task_unlock(tsk); > return buf; > } > > since some archs may do like > > char *strncpy(char *dest, const char *src, size_t n) > { > size_t len = __strnend(src, n) - src; > __builtin_memset(dest + len, 0, n - len); > __builtin_memcpy(dest, src, len); > return dest; > } > > ( arch/s390/lib/string.c ) after adding prctl(PR_SET_NAME)? I don't understand what you're asking, sorry.