From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8176C47404 for ; Mon, 7 Oct 2019 07:03:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F2C522473 for ; Mon, 7 Oct 2019 07:03:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727252AbfJGHDp (ORCPT ); Mon, 7 Oct 2019 03:03:45 -0400 Received: from mga02.intel.com ([134.134.136.20]:25273 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726202AbfJGHDp (ORCPT ); Mon, 7 Oct 2019 03:03:45 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Oct 2019 00:03:44 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,265,1566889200"; d="scan'208";a="394249606" Received: from ahunter-desktop.fi.intel.com ([10.237.72.66]) by fmsmga006.fm.intel.com with ESMTP; 07 Oct 2019 00:03:43 -0700 From: Adrian Hunter To: Arnaldo Carvalho de Melo , Jiri Olsa Cc: linux-kernel@vger.kernel.org Subject: [PATCH] perf tools: Fix mode setting in copyfile_mode_ns() Date: Mon, 7 Oct 2019 10:02:21 +0300 Message-Id: <20191007070221.11158-1-adrian.hunter@intel.com> X-Mailer: git-send-email 2.17.1 Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org slow_copyfile() opens the file by name, so "write" permissions must not be removed in copyfile_mode_ns() before calling slow_copyfile(). Example: Before: $ sudo chmod +r /proc/kcore $ sudo setcap "cap_sys_admin,cap_sys_ptrace,cap_syslog,cap_sys_rawio=ep" tools/perf/perf $ tools/perf/perf buildid-cache -k /proc/kcore Couldn't add /proc/kcore After: $ sudo chmod +r /proc/kcore $ sudo setcap "cap_sys_admin,cap_sys_ptrace,cap_syslog,cap_sys_rawio=ep" tools/perf/perf $ tools/perf/perf buildid-cache -v -k /proc/kcore kcore added to build-id cache directory /home/ahunter/.debug/[kernel.kcore]/37e340b1b5a7cf4f57ba8de2bc777359588a957f/2019100709562289 Signed-off-by: Adrian Hunter --- tools/perf/util/copyfile.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/copyfile.c b/tools/perf/util/copyfile.c index 3fa0db136667..47e03de7c235 100644 --- a/tools/perf/util/copyfile.c +++ b/tools/perf/util/copyfile.c @@ -101,14 +101,16 @@ static int copyfile_mode_ns(const char *from, const char *to, mode_t mode, if (tofd < 0) goto out; - if (fchmod(tofd, mode)) - goto out_close_to; - if (st.st_size == 0) { /* /proc? do it slowly... */ err = slow_copyfile(from, tmp, nsi); + if (!err && fchmod(tofd, mode)) + err = -1; goto out_close_to; } + if (fchmod(tofd, mode)) + goto out_close_to; + nsinfo__mountns_enter(nsi, &nsc); fromfd = open(from, O_RDONLY); nsinfo__mountns_exit(&nsc); -- 2.17.1