From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755570Ab3GBLIs (ORCPT ); Tue, 2 Jul 2013 07:08:48 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:36368 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755683Ab3GBLIo (ORCPT ); Tue, 2 Jul 2013 07:08:44 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Stephane Eranian , Ingo Molnar , Luis Henriques Subject: [PATCH 46/50] perf: Disable monitoring on setuid processes for regular users Date: Tue, 2 Jul 2013 12:07:34 +0100 Message-Id: <1372763258-20664-47-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1372763258-20664-1-git-send-email-luis.henriques@canonical.com> References: <1372763258-20664-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.16 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Stephane Eranian commit 2976b10f05bd7f6dab9f9e7524451ddfed656a89 upstream. There was a a bug in setup_new_exec(), whereby the test to disabled perf monitoring was not correct because the new credentials for the process were not yet committed and therefore the get_dumpable() test was never firing. The patch fixes the problem by moving the perf_event test until after the credentials are committed. Signed-off-by: Stephane Eranian Tested-by: Jiri Olsa Acked-by: Peter Zijlstra Signed-off-by: Ingo Molnar Signed-off-by: Luis Henriques --- fs/exec.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 5a76464..832763a 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1162,13 +1162,6 @@ void setup_new_exec(struct linux_binprm * bprm) set_dumpable(current->mm, suid_dumpable); } - /* - * Flush performance counters when crossing a - * security domain: - */ - if (!get_dumpable(current->mm)) - perf_event_exit_task(current); - /* An exec changes our domain. We are no longer part of the thread group */ @@ -1232,6 +1225,15 @@ void install_exec_creds(struct linux_binprm *bprm) commit_creds(bprm->cred); bprm->cred = NULL; + + /* + * Disable monitoring for regular users + * when executing setuid binaries. Must + * wait until new credentials are committed + * by commit_creds() above + */ + if (get_dumpable(current->mm) != SUID_DUMP_USER) + perf_event_exit_task(current); /* * cred_guard_mutex must be held at least to this point to prevent * ptrace_attach() from altering our determination of the task's -- 1.8.1.2