Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032944AbbKEO5z (ORCPT ); Thu, 5 Nov 2015 09:57:55 -0500 Received: from mail.kernel.org ([198.145.29.136]:38309 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1032853AbbKEO5w (ORCPT ); Thu, 5 Nov 2015 09:57:52 -0500 Date: Thu, 5 Nov 2015 11:57:47 -0300 From: Arnaldo Carvalho de Melo To: Wang Nan Cc: namhyung@kernel.org, lizefan@huawei.com, pi3orama@163.com, linux-kernel@vger.kernel.org, jolsa@kernel.org, masami.hiramatsu.pt@hitachi.com Subject: Re: [PATCH 1/2] perf probe: Only call probe_file__get_events() when fd is valid Message-ID: <20151105145747.GQ13236@kernel.org> References: <1446729565-27592-1-git-send-email-wangnan0@huawei.com> <1446729565-27592-2-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1446729565-27592-2-git-send-email-wangnan0@huawei.com> X-Url: http://acmel.wordpress.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 Content-Length: 2944 Lines: 96 Em Thu, Nov 05, 2015 at 01:19:24PM +0000, Wang Nan escreveu: > In system with kprobe enabled but uprobe turned off, 'perf probe -d' > causes segfault because it calls probe_file__get_events() with a > negative fd (when deleting uprobe events). > > This patch validates fds before calling probe_file__get_events(). Wouldn't this shorter patch be more robust by deferring the validation to just before using the 'fd' value? The end result is that probe_file__get_events() will return -ENOENT in both calls, so ret and ret2 will both be set to -ENOENT, as in your patch. Masami? - Arnaldo diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c index 89dbeb92c68e..f04a8318a1a7 100644 --- a/tools/perf/util/probe-file.c +++ b/tools/perf/util/probe-file.c @@ -138,6 +138,9 @@ struct strlist *probe_file__get_rawlist(int fd) char *p; struct strlist *sl; + if (fd < 0) + return NULL; + sl = strlist__new(NULL, NULL); fp = fdopen(dup(fd), "r"); diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c index 89dbeb92c68e..e5dc8e62f0f1 100644 --- a/tools/perf/util/probe-file.c +++ b/tools/perf/util/probe-file.c @@ -169,6 +169,9 @@ static struct strlist *__probe_file__get_namelist(int fd, bool include_group) struct probe_trace_event tev; int ret = 0; + if (fd < 0) + return NULL; + memset(&tev, 0, sizeof(tev)); rawlist = probe_file__get_rawlist(fd); if (!rawlist) > Signed-off-by: Wang Nan > Cc: Arnaldo Carvalho de Melo > Cc: Jiri Olsa > Cc: Masami Hiramatsu > Cc: Namhyung Kim > --- > tools/perf/builtin-probe.c | 12 ++++++++++-- > 1 file changed, 10 insertions(+), 2 deletions(-) > > diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c > index 132afc9..861aa89 100644 > --- a/tools/perf/builtin-probe.c > +++ b/tools/perf/builtin-probe.c > @@ -384,7 +384,11 @@ static int perf_del_probe_events(struct strfilter *filter) > goto out; > } > > - ret = probe_file__get_events(kfd, filter, klist); > + if (kfd < 0) > + ret = -ENOENT; > + else > + ret = probe_file__get_events(kfd, filter, klist); > + > if (ret == 0) { > strlist__for_each(ent, klist) > pr_info("Removed event: %s\n", ent->s); > @@ -394,7 +398,11 @@ static int perf_del_probe_events(struct strfilter *filter) > goto error; > } > > - ret2 = probe_file__get_events(ufd, filter, ulist); > + if (ufd < 0) > + ret2 = -ENOENT; > + else > + ret2 = probe_file__get_events(ufd, filter, ulist); > + > if (ret2 == 0) { > strlist__for_each(ent, ulist) > pr_info("Removed event: %s\n", ent->s); > -- > 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/