From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755145AbcEXJXg (ORCPT ); Tue, 24 May 2016 05:23:36 -0400 Received: from szxga01-in.huawei.com ([58.251.152.64]:52446 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752671AbcEXJXd (ORCPT ); Tue, 24 May 2016 05:23:33 -0400 From: Wang Nan To: CC: , , Wang Nan , Arnaldo Carvalho de Melo , Zefan Li Subject: [PATCH 1/2] perf tools: Check kptr_restrict for root Date: Tue, 24 May 2016 09:21:27 +0000 Message-ID: <1464081688-167940-1-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.193.248] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A090204.57441D88.007F,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 73aa766b3b31d27e93ee789f37fe8c5e Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If kptr_restrict is set to 2, even root is not allowed to see pointers. This patch checks kptr_restrict even if euid == 0. For root, report error if kptr_restrict is 2. Signed-off-by: Wang Nan Cc: Arnaldo Carvalho de Melo Cc: Zefan Li Cc: pi3orama@163.com --- tools/perf/util/symbol.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 20f9cb3..54c4ff2 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1933,17 +1933,17 @@ int setup_intlist(struct intlist **list, const char *list_str, static bool symbol__read_kptr_restrict(void) { bool value = false; + FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r"); - if (geteuid() != 0) { - FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r"); - if (fp != NULL) { - char line[8]; + if (fp != NULL) { + char line[8]; - if (fgets(line, sizeof(line), fp) != NULL) - value = atoi(line) != 0; + if (fgets(line, sizeof(line), fp) != NULL) + value = (geteuid() != 0) ? + (atoi(line) != 0) : + (atoi(line) == 2); - fclose(fp); - } + fclose(fp); } return value; -- 1.8.3.4