From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751798Ab3IFKmI (ORCPT ); Fri, 6 Sep 2013 06:42:08 -0400 Received: from smtp3-g21.free.fr ([212.27.42.3]:42563 "EHLO smtp3-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751553Ab3IFKmF (ORCPT ); Fri, 6 Sep 2013 06:42:05 -0400 From: Yann Droneaud To: linux-kernel@vger.kernel.org, Peter Zijlstra , Paul Mackerras , Ingo Molnar , Arnaldo Carvalho de Melo Cc: Yann Droneaud Subject: [PATCH v3 6/8] events: use get_unused_fd_flags(0) instead of get_unused_fd() Date: Fri, 6 Sep 2013 12:39:56 +0200 Message-Id: <1d9862e4cdccc52c4bb29e673834514cd263b181.1378460926.git.ydroneaud@opteya.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Macro get_unused_fd() is used to allocate a file descriptor with default flags. Those default flags (0) can be "unsafe": O_CLOEXEC must be used by default to not leak file descriptor across exec(). Instead of macro get_unused_fd(), functions anon_inode_getfd() or get_unused_fd_flags() should be used with flags given by userspace. If not possible, flags should be set to O_CLOEXEC to provide userspace with a default safe behavor. In a further patch, get_unused_fd() will be removed so that new code start using anon_inode_getfd() or get_unused_fd_flags() with correct flags. This patch replaces calls to get_unused_fd() with equivalent call to get_unused_fd_flags(0) to preserve current behavor for existing code. The hard coded flag value (0) should be reviewed on a per-subsystem basis, and, if possible, set to O_CLOEXEC. Signed-off-by: Yann Droneaud Link: http://lkml.kernel.org/r/cover.1378460926.git.ydroneaud@opteya.com --- kernel/events/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 2207efc..b12fdd3 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -6935,7 +6935,7 @@ SYSCALL_DEFINE5(perf_event_open, if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) return -EINVAL; - event_fd = get_unused_fd(); + event_fd = get_unused_fd_flags(0); if (event_fd < 0) return event_fd; -- 1.8.3.1