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 66D54C43217 for ; Wed, 12 Oct 2022 10:45:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229830AbiJLKp1 (ORCPT ); Wed, 12 Oct 2022 06:45:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35438 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229814AbiJLKpW (ORCPT ); Wed, 12 Oct 2022 06:45:22 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4BFAB4E609 for ; Wed, 12 Oct 2022 03:45:20 -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 dfw.source.kernel.org (Postfix) with ESMTPS id D0682614A1 for ; Wed, 12 Oct 2022 10:45:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38164C43143; Wed, 12 Oct 2022 10:45:19 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.96) (envelope-from ) id 1oiZF0-0047RC-1Q; Wed, 12 Oct 2022 06:45:34 -0400 Message-ID: <20221012104055.421393330@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 12 Oct 2022 06:40:55 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Andrew Morton , Tom Zanussi Subject: [PATCH v2 0/3] tracing: Fix synthetic event bug Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The follow commands caused a crash: # cd /sys/kernel/tracing # echo 's:open char file[]' > dynamic_events # echo 'hist:keys=common_pid:file=filename:onchange($file).trace(open,$file)' > events/syscalls/sys_enter_openat/trigger' # echo 1 > events/synthetic/open/enable BOOM! The problem is that the synthetic event field "char file[]" will read the value given to it as a string without any memory checks to make sure the address is valid. The above example will pass in the user space address and the sythetic event code will happily call strlen() on it and then strscpy() where either one will cause an oops when accessing user space addresses. Changes since v1: https://lore.kernel.org/all/20221011212501.773319898@goodmis.org/ - Handle "(fault)" printing when there's a fault Steven Rostedt (Google) (3): tracing: Move duplicate code of trace_kprobe/eprobe.c into header tracing: Add "(fault)" name injection to kernel probes tracing: Fix reading strings from synthetic events ---- kernel/trace/trace_eprobe.c | 60 ++------------------ kernel/trace/trace_events_synth.c | 23 ++++++-- kernel/trace/trace_kprobe.c | 60 ++------------------ kernel/trace/trace_probe_kernel.h | 115 ++++++++++++++++++++++++++++++++++++++ 4 files changed, 142 insertions(+), 116 deletions(-) create mode 100644 kernel/trace/trace_probe_kernel.h