From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752059AbcF3A4H (ORCPT ); Wed, 29 Jun 2016 20:56:07 -0400 Received: from mga03.intel.com ([134.134.136.65]:23798 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751781AbcF3A4F (ORCPT ); Wed, 29 Jun 2016 20:56:05 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,549,1459839600"; d="scan'208";a="986009503" From: Tom Zanussi To: rostedt@goodmis.org Cc: dvyukov@google.com, linux-kernel@vger.kernel.org, Tom Zanussi Subject: [PATCH 1/2] tracing: Fix use-after-free in hist_unreg_all/hist_enable_unreg_all Date: Wed, 29 Jun 2016 19:55:59 -0500 Message-Id: X-Mailer: git-send-email 1.9.3 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 From: Steven Rostedt While running tools/testing/selftests test suite with KASAN, Dmitry Vyukov hit the following use-after-free report: ================================================================== BUG: KASAN: use-after-free in hist_unreg_all+0x1a1/0x1d0 at addr ffff880031632cc0 Read of size 8 by task ftracetest/7413 ================================================================== BUG kmalloc-128 (Not tainted): kasan: bad access detected ------------------------------------------------------------------ This fixes the problem, along with the same problem in hist_enable_unreg_all(). Signed-off-by: Steven Rostedt [Copied Steve's hist_enable_unreg_all() fix to hist_unreg_all()] Signed-off-by: Tom Zanussi Cc: Dmitry Vyukov --- kernel/trace/trace_events_hist.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 0c05b8a..19ae135 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1500,9 +1500,9 @@ static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, static void hist_unreg_all(struct trace_event_file *file) { - struct event_trigger_data *test; + struct event_trigger_data *test, *n; - list_for_each_entry_rcu(test, &file->triggers, list) { + list_for_each_entry_safe(test, n, &file->triggers, list) { if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { list_del_rcu(&test->list); trace_event_trigger_enable_disable(file, 0); @@ -1699,9 +1699,9 @@ hist_enable_get_trigger_ops(char *cmd, char *param) static void hist_enable_unreg_all(struct trace_event_file *file) { - struct event_trigger_data *test; + struct event_trigger_data *test, *n; - list_for_each_entry_rcu(test, &file->triggers, list) { + list_for_each_entry_safe(test, n, &file->triggers, list) { if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { list_del_rcu(&test->list); update_cond_flag(file); -- 1.9.3