From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753418AbbCMJrC (ORCPT ); Fri, 13 Mar 2015 05:47:02 -0400 Received: from mail-pd0-f179.google.com ([209.85.192.179]:40771 "EHLO mail-pd0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751778AbbCMJq6 (ORCPT ); Fri, 13 Mar 2015 05:46:58 -0400 Date: Fri, 13 Mar 2015 18:46:15 +0900 From: Namhyung Kim To: Wang Nan Cc: acme@kernel.org, jolsa@kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, lizefan@huawei.com, pi3orama@163.com Subject: Re: [PATCH] perf: fix a segfault problem. Message-ID: <20150313094615.GC10836@danjae.skbroadband> References: <1426236092-197137-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1426236092-197137-1-git-send-email-wangnan0@huawei.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 13, 2015 at 08:41:32AM +0000, Wang Nan wrote: > Without this patch, perf report cause segfault if pass "" as '-t': > > $ perf report -t "" > > # To display the perf.data header info, please use --header/--header-only options. > # > # Samples: 37 of event 'syscalls:sys_enter_write' > # Event count (approx.): 37 > # > # Children SelfCommand Shared Object Symbol > Segmentation fault > > This patch avoid the segfault by checking empty string for > 'symbol_conf.field_sep'. What about resetting it to NULL if empty string was given? Thanks, Namhyung > > Signed-off-by: Wang Nan > --- > tools/perf/util/sort.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c > index 4593f36..7f563a0 100644 > --- a/tools/perf/util/sort.c > +++ b/tools/perf/util/sort.c > @@ -31,7 +31,8 @@ static int repsep_snprintf(char *bf, size_t size, const char *fmt, ...) > > va_start(ap, fmt); > n = vsnprintf(bf, size, fmt, ap); > - if (symbol_conf.field_sep && n > 0) { > + if (symbol_conf.field_sep && n > 0 && > + (symbol_conf.field_sep[0] != '\0')) { > char *sep = bf; > > while (1) { > -- > 1.8.3.4 >