From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F2F5C43457 for ; Wed, 14 Oct 2020 17:38:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3923C221EB for ; Wed, 14 Oct 2020 17:38:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389759AbgJNRif (ORCPT ); Wed, 14 Oct 2020 13:38:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:57684 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389565AbgJNRhb (ORCPT ); Wed, 14 Oct 2020 13:37:31 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D736122280; Wed, 14 Oct 2020 17:37:30 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94) (envelope-from ) id 1kSkiP-002yJb-Mr; Wed, 14 Oct 2020 13:37:29 -0400 Message-ID: <20201014173729.577913194@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 14 Oct 2020 13:36:57 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Masami Hiramatsu , Tom Zanussi Subject: [for-next][PATCH 10/12] tracing: Handle synthetic event array field type checking correctly References: <20201014173647.955053902@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tom Zanussi Since synthetic event array types are derived from the field name, there may be a semicolon at the end of the type which should be stripped off. If there are more characters following that, normal type string checking will result in an invalid type. Without this patch, you can end up with an invalid field type string that gets displayed in both the synthetic event description and the event format: Before: # echo 'myevent char str[16]; int v' >> synthetic_events # cat synthetic_events myevent char[16]; str; int v name: myevent ID: 1936 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:char str[16];; offset:8; size:16; signed:1; field:int v; offset:40; size:4; signed:1; print fmt: "str=%s, v=%d", REC->str, REC->v After: # echo 'myevent char str[16]; int v' >> synthetic_events # cat synthetic_events myevent char[16] str; int v # cat events/synthetic/myevent/format name: myevent ID: 1936 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:char str[16]; offset:8; size:16; signed:1; field:int v; offset:40; size:4; signed:1; print fmt: "str=%s, v=%d", REC->str, REC->v Link: https://lkml.kernel.org/r/6587663b56c2d45ab9d8c8472a2110713cdec97d.1602598160.git.zanussi@kernel.org [ : wrote parse_synth_field() snippet. ] Fixes: 4b147936fa50 (tracing: Add support for 'synthetic' events) Reported-by: Masami Hiramatsu Tested-by: Masami Hiramatsu Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_events_synth.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index f77851018121..d239f0e2af8f 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -174,7 +174,7 @@ static int synth_field_string_size(char *type) start += sizeof("char[") - 1; end = strchr(type, ']'); - if (!end || end < start) + if (!end || end < start || type + strlen(type) > end + 1) return -EINVAL; len = end - start; @@ -625,8 +625,14 @@ static struct synth_field *parse_synth_field(int argc, const char **argv, if (field_type[0] == ';') field_type++; len = strlen(field_type) + 1; - if (array) - len += strlen(array); + + if (array) { + int l = strlen(array); + + if (l && array[l - 1] == ';') + l--; + len += l; + } if (prefix) len += strlen(prefix); -- 2.28.0