From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753890Ab3AUVT0 (ORCPT ); Mon, 21 Jan 2013 16:19:26 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:33581 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752030Ab3AUVRa (ORCPT ); Mon, 21 Jan 2013 16:17:30 -0500 X-Authority-Analysis: v=2.0 cv=C91rOHz+ c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=Ciwy3NGCPMMA:10 a=1qUcW2b0jkwA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=meVymXHHAAAA:8 a=WFGCPMuA9KsA:10 a=3nbZYyFuAAAA:8 a=VwQbUJbxAAAA:8 a=xt1qIhzxAAAA:8 a=lcmWLoirjDfMRU8MAagA:9 a=EvKJbDF4Ut8A:10 a=jeBq3FmKZ4MA:10 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 74.67.115.198 Message-Id: <20130121211728.177153584@goodmis.org> User-Agent: quilt/0.60-1 Date: Mon, 21 Jan 2013 16:14:09 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker , Hiraku Toyooka Subject: [PATCH 06/13 -next] tracing: Add checks if tr->buffer is NULL in tracing_reset{_online_cpus} References: <20130121211403.337052956@goodmis.org> Content-Disposition: inline; filename=0006-tracing-Add-checks-if-tr-buffer-is-NULL-in-tracing_r.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Hiraku Toyooka max_tr->buffer could be NULL in the tracing_reset{_online_cpus}. In this case, a NULL pointer dereference happens, so we should return immediately from these functions. Note, the current code does not call tracing_reset*() with max_tr when its buffer is NULL, but future code will. This patch is needed to prevent the future code from crashing. Link: http://lkml.kernel.org/r/20121219070234.31200.93863.stgit@liselsia Signed-off-by: Hiraku Toyooka Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f8b7c62..72b171b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -922,6 +922,9 @@ void tracing_reset(struct trace_array *tr, int cpu) { struct ring_buffer *buffer = tr->buffer; + if (!buffer) + return; + ring_buffer_record_disable(buffer); /* Make sure all commits have finished */ @@ -936,6 +939,9 @@ void tracing_reset_online_cpus(struct trace_array *tr) struct ring_buffer *buffer = tr->buffer; int cpu; + if (!buffer) + return; + ring_buffer_record_disable(buffer); /* Make sure all commits have finished */ -- 1.7.10.4