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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6DD8C4332F for ; Wed, 8 Nov 2023 11:01:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344346AbjKHLB5 (ORCPT ); Wed, 8 Nov 2023 06:01:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230314AbjKHLB4 (ORCPT ); Wed, 8 Nov 2023 06:01:56 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 103E0101 for ; Wed, 8 Nov 2023 03:01:54 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C0B40C433C7; Wed, 8 Nov 2023 11:01:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699441313; bh=+R6IRRsGnNFGnMhbq9xit7QVk0XL4ypGTQcZDA737NY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=V5Q02HL3IXtlPK9z6kq55ayWhIbUmg2Lv/i6XaoQJwSbbePbFimAkKoZmSSceJrsI NxzuAilkBkE6kFjdAcLtlAGvt/Uagh57tEbNCP0pdOQRWAyDXEAw+eEl1rez31z0oH trS9HezYVSubeiBPFz8/SnYp/XgaTRJwSIUjFVgINmE0nzCYuekX8BB8nkWQ7qbYvA Ao9lgvuJj0hZwrryP2UTVKvgqKWhYbKswHjc+HJXCSDoN17wAFJu6hugaWo5EOOPid GIF2H36Ze0gtkikeJLk634XGavud4xt+0YtrZvnrvQhaYaVp3/ojize+ANR+xO+emQ cVFAcUjvFt/bw== Date: Wed, 8 Nov 2023 20:01:50 +0900 From: Masami Hiramatsu (Google) To: Masami Hiramatsu (Google) Cc: Steven Rostedt , linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] tracing: fprobe-event: Fix to check tracepoint event and return Message-Id: <20231108200150.69541f243099eb6128ba4554@kernel.org> In-Reply-To: <20231107094045.db1d982c42712b8f26891ec6@kernel.org> References: <169902753361.313086.6662802092416198593.stgit@devnote2> <20231106172811.25066d33@gandalf.local.home> <20231107094045.db1d982c42712b8f26891ec6@kernel.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; 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 Tue, 7 Nov 2023 09:40:45 +0900 Masami Hiramatsu (Google) wrote: > On Mon, 6 Nov 2023 17:28:11 -0500 > Steven Rostedt wrote: > > > On Sat, 4 Nov 2023 01:05:34 +0900 > > "Masami Hiramatsu (Google)" wrote: > > > > > From: Masami Hiramatsu (Google) > > > > > > Fix to check the tracepoint event is not valid with $retval. > > > The commit 08c9306fc2e3 ("tracing/fprobe-event: Assume fprobe is > > > a return event by $retval") introduced automatic return probe > > > conversion with $retval. But since tracepoint event does not > > > support return probe, $retval is not acceptable. > > > > Can you add the command that causes this to fail. > > Actually this doesn't command fail but it expected to fail. > > $ echo "t kfree $retval" >> dynamic_events Wait, with some configuration, this doesn't cause a problem. Let me try to reproduce the issue... Thank you, > > This should be rejected because 't' (tracepoint) should not be > a return probe. Without this fix, this is accepted. > (But it traces a random return value because the tracepoint function > will return 'void'.) > > Thank you, > > > > > -- Steve > > > > > > > > Fixes: 08c9306fc2e3 ("tracing/fprobe-event: Assume fprobe is a return event by $retval") > > > Cc: stable@vger.kernel.org > > > Signed-off-by: Masami Hiramatsu (Google) > > > --- > > > kernel/trace/trace_fprobe.c | 9 +++++---- > > > 1 file changed, 5 insertions(+), 4 deletions(-) > > > > > > diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c > > > index 8bfe23af9c73..7d2ddbcfa377 100644 > > > --- a/kernel/trace/trace_fprobe.c > > > +++ b/kernel/trace/trace_fprobe.c > > > @@ -927,11 +927,12 @@ static int parse_symbol_and_return(int argc, const char *argv[], > > > for (i = 2; i < argc; i++) { > > > tmp = strstr(argv[i], "$retval"); > > > if (tmp && !isalnum(tmp[7]) && tmp[7] != '_') { > > > + if (is_tracepoint) { > > > + trace_probe_log_set_index(i); > > > + trace_probe_log_err(tmp - argv[i], RETVAL_ON_PROBE); > > > + return -EINVAL; > > > + } > > > *is_return = true; > > > - /* > > > - * NOTE: Don't check is_tracepoint here, because it will > > > - * be checked when the argument is parsed. > > > - */ > > > break; > > > } > > > } > > > > > -- > Masami Hiramatsu (Google) -- Masami Hiramatsu (Google)