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 E063EC433F5 for ; Tue, 24 May 2022 22:34:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242392AbiEXWeU (ORCPT ); Tue, 24 May 2022 18:34:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57116 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229731AbiEXWeP (ORCPT ); Tue, 24 May 2022 18:34:15 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCAEE6D4C4 for ; Tue, 24 May 2022 15:34:14 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 7D744B81A52 for ; Tue, 24 May 2022 22:34:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F28BC34100; Tue, 24 May 2022 22:34:11 +0000 (UTC) Date: Tue, 24 May 2022 18:34:03 -0400 From: Steven Rostedt To: Linyu Yuan Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Masami Hiramatsu , Tom Zanussi Subject: Re: [PATCH 2/2] tracing/probes: make match function safe Message-ID: References: <1651397651-30454-1-git-send-email-quic_linyyuan@quicinc.com> <1651397651-30454-3-git-send-email-quic_linyyuan@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1651397651-30454-3-git-send-email-quic_linyyuan@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Masami and Tom, what are you thoughts on this? -- Steve On Sun, May 01, 2022 at 05:34:11PM +0800, Linyu Yuan wrote: > When delete one kprobe/uprobe/eprobe event entry > using /sys/kernel/debug/tracing/dynamic_events file, > it will loop all dynamic envent entries, > as user will not input dyn_event_operations type, > when call the match function of kprobe/uprobe/eprobe, > the dynamic event may have different dyn_event_operations type, > but currently match function may return a match. > > Fix by check dyn_event_operations type first. > > Signed-off-by: Linyu Yuan > --- > kernel/trace/trace_eprobe.c | 31 +++++++++++++++++++++++-------- > kernel/trace/trace_kprobe.c | 3 +++ > kernel/trace/trace_uprobe.c | 3 +++ > 3 files changed, 29 insertions(+), 8 deletions(-) > > diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c > index b16e067..0029840 100644 > --- a/kernel/trace/trace_eprobe.c > +++ b/kernel/trace/trace_eprobe.c > @@ -19,6 +19,21 @@ > > #define EPROBE_EVENT_SYSTEM "eprobes" > > +static int eprobe_dyn_event_create(const char *raw_command); > +static int eprobe_dyn_event_show(struct seq_file *m, struct dyn_event *ev); > +static bool eprobe_dyn_event_is_busy(struct dyn_event *ev); > +static int eprobe_dyn_event_release(struct dyn_event *ev); > +static bool eprobe_dyn_event_match(const char *system, const char *event, > + int argc, const char **argv, struct dyn_event *ev); > + > +static struct dyn_event_operations eprobe_dyn_event_ops = { > + .create = eprobe_dyn_event_create, > + .show = eprobe_dyn_event_show, > + .is_busy = eprobe_dyn_event_is_busy, > + .free = eprobe_dyn_event_release, > + .match = eprobe_dyn_event_match, > +}; > + > struct trace_eprobe { > /* tracepoint system */ > const char *event_system; > @@ -39,6 +54,11 @@ struct eprobe_data { > > static int __trace_eprobe_create(int argc, const char *argv[]); > > +static bool is_trace_eprobe(struct dyn_event *ev) > +{ > + return ev->ops == &eprobe_dyn_event_ops; > +} > + > static void trace_event_probe_cleanup(struct trace_eprobe *ep) > { > if (!ep) > @@ -121,6 +141,9 @@ static bool eprobe_dyn_event_match(const char *system, const char *event, > struct trace_eprobe *ep = to_trace_eprobe(ev); > const char *slash; > > + if (!is_trace_eprobe(ev)) > + return false; > + > /* > * We match the following: > * event only - match all eprobes with event name > @@ -174,14 +197,6 @@ static bool eprobe_dyn_event_match(const char *system, const char *event, > return trace_probe_match_command_args(&ep->tp, argc, argv); > } > > -static struct dyn_event_operations eprobe_dyn_event_ops = { > - .create = eprobe_dyn_event_create, > - .show = eprobe_dyn_event_show, > - .is_busy = eprobe_dyn_event_is_busy, > - .free = eprobe_dyn_event_release, > - .match = eprobe_dyn_event_match, > -}; > - > static struct trace_eprobe *alloc_event_probe(const char *group, > const char *this_event, > struct trace_event_call *event, > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > index 2cd8ef9..f63abfa 100644 > --- a/kernel/trace/trace_kprobe.c > +++ b/kernel/trace/trace_kprobe.c > @@ -163,6 +163,9 @@ static bool trace_kprobe_match(const char *system, const char *event, > { > struct trace_kprobe *tk = to_trace_kprobe(ev); > > + if (!is_trace_kprobe(ev)) > + return false; > + > return (event[0] == '\0' || > strcmp(trace_probe_name(&tk->tp), event) == 0) && > (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0) && > diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c > index a935c08..ee55ed0 100644 > --- a/kernel/trace/trace_uprobe.c > +++ b/kernel/trace/trace_uprobe.c > @@ -312,6 +312,9 @@ static bool trace_uprobe_match(const char *system, const char *event, > { > struct trace_uprobe *tu = to_trace_uprobe(ev); > > + if (!is_trace_uprobe(ev)) > + return false; > + > return (event[0] == '\0' || > strcmp(trace_probe_name(&tu->tp), event) == 0) && > (!system || strcmp(trace_probe_group_name(&tu->tp), system) == 0) && > -- > 2.7.4