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=-8.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_2 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 2CF43C4363C for ; Sat, 3 Oct 2020 01:00:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CE8AD206FA for ; Sat, 3 Oct 2020 01:00:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725730AbgJCBAj (ORCPT ); Fri, 2 Oct 2020 21:00:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:60462 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725283AbgJCBAj (ORCPT ); Fri, 2 Oct 2020 21:00:39 -0400 Received: from oasis.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 6C84A206F8; Sat, 3 Oct 2020 01:00:38 +0000 (UTC) Date: Fri, 2 Oct 2020 21:00:36 -0400 From: Steven Rostedt To: Tom Zanussi Cc: axelrasmussen@google.com, mhiramat@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 0/3] tracing: Add dynamic strings for synthetic events Message-ID: <20201002210036.0200371b@oasis.local.home> In-Reply-To: References: X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 1 Oct 2020 16:46:43 -0500 Tom Zanussi wrote: > Hi, > > This is v3 of the dynamic string support for synthetic events. > > No code changes since v2, just added Fixes: tag for 'tracing: Fix > parse_synth_field() error handling' as suggested by Masami along with > his Reviewed-by, and Axel's Tested-bys. > I also added this for a bit of paranoid, and probably should be a separate patch, just to make sure if the string isn't nul terminated, this will keep it from bleeding pass the end of the string. -- Steve diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index 4b3ec570147a..d81739990a53 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -234,7 +234,7 @@ static const char *synth_field_fmt(char *type) else if (strcmp(type, "gfp_t") == 0) fmt = "%x"; else if (synth_field_is_string(type)) - fmt = "%s"; + fmt = "%.*s"; return fmt; } @@ -303,11 +303,13 @@ static enum print_line_t print_synth_event(struct trace_iterator *iter, str_field = (char *)entry + data_offset; trace_seq_printf(s, print_fmt, se->fields[i]->name, + STR_VAR_LEN_MAX, str_field, i == se->n_fields - 1 ? "" : " "); n_u64++; } else { trace_seq_printf(s, print_fmt, se->fields[i]->name, + STR_VAR_LEN_MAX, (char *)&entry->fields[n_u64], i == se->n_fields - 1 ? "" : " "); n_u64 += STR_VAR_LEN_MAX / sizeof(u64);