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 92867C4332F for ; Tue, 7 Nov 2023 00:40:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233408AbjKGAky (ORCPT ); Mon, 6 Nov 2023 19:40:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53014 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232821AbjKGAkw (ORCPT ); Mon, 6 Nov 2023 19:40:52 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8FDA21BF for ; Mon, 6 Nov 2023 16:40:49 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 33B8CC433C7; Tue, 7 Nov 2023 00:40:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699317649; bh=/XpXG2F9SG0xMGW2+ycU4gMGALDI8qHOnUTmJhAQsMM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=l7mBYws+qxsXIfiDgkvJ5xM0GQzcjV/nG6yf/ADJQKUao/Eb95s7lgZdXqLSx7vZF 8nnEaUKorFqpRDSX+UESXJg4hIukMQ4v00BY2WJF8QxBu808SgRNy9aYBy4J7Y5Gjv MQLpZyH0yt+K3zpC6C9kftGNFxnSdtQ0ZXpmTiPXKQeWc7NRKkhyEYdfx76eCQfb2H KSFbby5umpgOEJQXeM55ejgxbeTVADc96aF8OVCgqCJyzhtuTvQzm3FmsOTzOH9PvY l+QqnuclLT9V2g9Oe5O/dfcBfFvx/GWf68+Le+E1D707cPCDdqPoPVsHcWfbRArns7 yHtW2+SC+DbiQ== Date: Tue, 7 Nov 2023 09:40:45 +0900 From: Masami Hiramatsu (Google) To: Steven Rostedt Cc: 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: <20231107094045.db1d982c42712b8f26891ec6@kernel.org> In-Reply-To: <20231106172811.25066d33@gandalf.local.home> References: <169902753361.313086.6662802092416198593.stgit@devnote2> <20231106172811.25066d33@gandalf.local.home> 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 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 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)