From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E784B2DECAA; Fri, 18 Jul 2025 17:55:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752861361; cv=none; b=lBu8TORQyBYs/jESdeG89yNNmmnlesgHAPY5TKkWWOcEbnLMqK7T4Z8cMAMA5v4IxJXUZGr0fVVjVB9S8Kl9aB4CgOjitHKpeHoO1c/IMI5P/riji0W2a6Pp1bcID2d2xBgrcY7FIsDJsCdM6PUJoGpL+zUuJ2wgXBq7z5+Fkio= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752861361; c=relaxed/simple; bh=lD/JCFakuUElJ2BVsQtIXUmGdNp8eUEkV6kqDpFooBA=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=EobRFyD7uD2llEM1kA9QGdWfK9og1R+011luBzfBLt5WlTejGriwFEXGIMrstMUPYoeyMguFKukB+EbLj258TZpqELbKUrKqnOuioauWUwFreZoIYtiMyxM0Acndgv4RIEVae8adxqtui95u9RGQxXsk8jE1YHNKoBJlwv8Kcb0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 944B710A7F7; Fri, 18 Jul 2025 17:55:52 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf09.hostedemail.com (Postfix) with ESMTPA id F149120028; Fri, 18 Jul 2025 17:55:50 +0000 (UTC) Date: Fri, 18 Jul 2025 13:55:49 -0400 From: Steven Rostedt To: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH 4/5] tracing: eprobe-event: Allocate string buffers from heap Message-ID: <20250718135549.387b98ab@batman.local.home> In-Reply-To: <175283848063.343578.12113784863348416166.stgit@devnote2> References: <175283843771.343578.8524137568048302760.stgit@devnote2> <175283848063.343578.12113784863348416166.stgit@devnote2> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: i8u5ds8qb5u4pf5tgohhzrpy13ih7shn X-Rspamd-Server: rspamout07 X-Rspamd-Queue-Id: F149120028 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1+f1kfNTgW9AW8Wz5tLPVZedW1+1de5Afc= X-HE-Tag: 1752861350-668683 X-HE-Meta: U2FsdGVkX1/WE/6urmYczhVqGk1BcfM05fcfC7gS0K13bUfG7FSSqWXmitBKiTX0OlZvMJnjrnxu44gjFtXVUUKJuD+OYRmtsOslXRQ7jpGeDNpvNqW/1Ze5w9pY8Oi0IBr/qP2NdVSqnNS7qMp2QWojM+1oD19jkH9NWybVRVhSdbl0LUKjTHIeDqOFqvsOkzdW7afMffS12HJDtDucRF2mNRzlnauW3fuo8rA5HafUy6lD2aP2NE5lGtyK5mC+5dB9AlCpTTUB990PyYG87QdyS45Gdmm/ep8yOD9p9FcEpXBRsb/iMioxOlVbdEV1dJWudWG+55Ugurk8Wl3+jGWwhsneJFg5tHtiWbYiv2clltTQmm85Eg== On Fri, 18 Jul 2025 20:34:40 +0900 "Masami Hiramatsu (Google)" wrote: > From: Masami Hiramatsu (Google) > > Allocate temporary string buffers for parsing eprobe-events > from heap instead of stack. > > Signed-off-by: Masami Hiramatsu (Google) > --- > kernel/trace/trace_eprobe.c | 24 ++++++++++++++++++++---- > 1 file changed, 20 insertions(+), 4 deletions(-) > > diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c > index 1e18a8619b40..75d8208cd859 100644 > --- a/kernel/trace/trace_eprobe.c > +++ b/kernel/trace/trace_eprobe.c > @@ -9,6 +9,7 @@ > * Copyright (C) 2021, VMware Inc, Tzvetomir Stoyanov tz.stoyanov@gmail.com> > * > */ > +#include > #include > #include > #include > @@ -871,10 +872,10 @@ static int __trace_eprobe_create(int argc, const char *argv[]) > const char *event = NULL, *group = EPROBE_EVENT_SYSTEM; > const char *sys_event = NULL, *sys_name = NULL; > struct trace_event_call *event_call; > + char *buf1 __free(kfree) = NULL; > + char *buf2 __free(kfree) = NULL; > + char *gbuf __free(kfree) = NULL; > struct trace_eprobe *ep = NULL; > - char buf1[MAX_EVENT_NAME_LEN]; > - char buf2[MAX_EVENT_NAME_LEN]; > - char gbuf[MAX_EVENT_NAME_LEN]; > int ret = 0, filter_idx = 0; > int i, filter_cnt; > > @@ -885,6 +886,11 @@ static int __trace_eprobe_create(int argc, const char *argv[]) > > event = strchr(&argv[0][1], ':'); > if (event) { > + gbuf = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL); > + if (!gbuf) { > + ret = -ENOMEM; > + goto parse_error; > + } > event++; > ret = traceprobe_parse_event_name(&event, &group, gbuf, > event - argv[0]); > @@ -894,6 +900,12 @@ static int __trace_eprobe_create(int argc, const char *argv[]) > > trace_probe_log_set_index(1); > sys_event = argv[1]; > + > + buf2 = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL); > + if (!buf2) { > + ret = -ENOMEM; > + goto parse_error; > + } > ret = traceprobe_parse_event_name(&sys_event, &sys_name, buf2, 0); > if (ret || !sys_event || !sys_name) { > trace_probe_log_err(0, NO_EVENT_INFO); > @@ -901,7 +913,11 @@ static int __trace_eprobe_create(int argc, const char *argv[]) > } > > if (!event) { > - strscpy(buf1, sys_event, MAX_EVENT_NAME_LEN); > + buf1 = kstrdup(sys_event, GFP_KERNEL); > + if (!buf1) { > + ret = -ENOMEM; > + goto error; > + } I kinda hate all these updating of "ret" before jumping to error. > event = buf1; > } > What about this: -- Steve diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c index 916555f0de81..48cc1079a1dd 100644 --- a/kernel/trace/trace_eprobe.c +++ b/kernel/trace/trace_eprobe.c @@ -9,6 +9,7 @@ * Copyright (C) 2021, VMware Inc, Tzvetomir Stoyanov tz.stoyanov@gmail.com> * */ +#include #include #include #include @@ -869,10 +870,10 @@ static int __trace_eprobe_create(int argc, const char *argv[]) const char *event = NULL, *group = EPROBE_EVENT_SYSTEM; const char *sys_event = NULL, *sys_name = NULL; struct trace_event_call *event_call; + char *buf1 __free(kfree) = NULL; + char *buf2 __free(kfree) = NULL; + char *gbuf __free(kfree) = NULL; struct trace_eprobe *ep = NULL; - char buf1[MAX_EVENT_NAME_LEN]; - char buf2[MAX_EVENT_NAME_LEN]; - char gbuf[MAX_EVENT_NAME_LEN]; int ret = 0, filter_idx = 0; int i, filter_cnt; @@ -883,6 +884,9 @@ static int __trace_eprobe_create(int argc, const char *argv[]) event = strchr(&argv[0][1], ':'); if (event) { + gbuf = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL); + if (!gbuf) + goto mem_error; event++; ret = traceprobe_parse_event_name(&event, &group, gbuf, event - argv[0]); @@ -892,6 +896,10 @@ static int __trace_eprobe_create(int argc, const char *argv[]) trace_probe_log_set_index(1); sys_event = argv[1]; + + buf2 = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL); + if (!buf2) + goto mem_error; ret = traceprobe_parse_event_name(&sys_event, &sys_name, buf2, 0); if (ret || !sys_event || !sys_name) { trace_probe_log_err(0, NO_EVENT_INFO); @@ -899,7 +907,9 @@ static int __trace_eprobe_create(int argc, const char *argv[]) } if (!event) { - strscpy(buf1, sys_event, MAX_EVENT_NAME_LEN); + buf1 = kstrdup(sys_event, GFP_KERNEL); + if (!buf1) + goto mem_error; event = buf1; } @@ -972,6 +982,9 @@ static int __trace_eprobe_create(int argc, const char *argv[]) trace_probe_log_clear(); return ret; +mem_error: + ret = -ENOMEM; + goto error; parse_error: ret = -EINVAL; error: