From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 284EEBA34; Mon, 6 Jan 2025 15:50:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736178644; cv=none; b=iQBqkClTAuJ0I36eS9QhzP3xK5HfLQ/CiuxVEfHn7HZzv6/sGzDtD+HcvjySa0hLfwQaBPi7hZeJDsPa8F0bUTsEbuusCO1ZVbgB770PqtVFOQEGYoFMkViRVHnlxsasXisTj+dBUi6b07zjSnBBqg2wWjuUmsGWNvR3JPeRIdY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736178644; c=relaxed/simple; bh=zWrTSvVs4g7yFzS2EJ+x6UtGCP6lrCMvIxltpiAVCgk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aivAwNYwFJ4UHzgS21IpR4l9Gq5cmZWylyPoO0kasoxVvgSb+tb5wO5XTPOmiIEH1uSIu1wjNibvgJi1uMNpac2NGfcKbIGNgcNcLYz7JQDccTYpd9fD8NfX/XzF2ouSOiEXm4ES8hke5xmJkGN9khFWmo5tDe/auA/aBnsZzLk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=EPH5Rang; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="EPH5Rang" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 37035C4CED2; Mon, 6 Jan 2025 15:50:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1736178643; bh=zWrTSvVs4g7yFzS2EJ+x6UtGCP6lrCMvIxltpiAVCgk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EPH5RangiPb1V6ytF66/TdHMn0nd8bC8LceagGSnlGJe/MFXNg+3FCk8xMMiCB23m mPe6jF3mK0XcTF5UgrJgcpCaaFRNS0Ucr2EGEvVO1zaOkQsGDM4YlC9gb1/zSpvFk8 CrHEzrn0dWN/6VbVhNIDDbKyJ559UpeHwr2fv4+M= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Al Viro , Linus Torvalds , "Steven Rostedt (Google)" Subject: [PATCH 5.15 046/168] tracing: Add missing helper functions in event pointer dereference check Date: Mon, 6 Jan 2025 16:15:54 +0100 Message-ID: <20250106151140.202990461@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250106151138.451846855@linuxfoundation.org> References: <20250106151138.451846855@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steven Rostedt commit 917110481f6bc1c96b1e54b62bb114137fbc6d17 upstream. The process_pointer() helper function looks to see if various trace event macros are used. These macros are for storing data in the event. This makes it safe to dereference as the dereference will then point into the event on the ring buffer where the content of the data stays with the event itself. A few helper functions were missing. Those were: __get_rel_dynamic_array() __get_dynamic_array_len() __get_rel_dynamic_array_len() __get_rel_sockaddr() Also add a helper function find_print_string() to not need to use a middle man variable to test if the string exists. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Mathieu Desnoyers Cc: Andrew Morton Cc: Al Viro Cc: Linus Torvalds Link: https://lore.kernel.org/20241217024720.521836792@goodmis.org Fixes: 5013f454a352c ("tracing: Add check of trace event print fmts for dereferencing pointers") Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace_events.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -257,6 +257,15 @@ static bool test_field(const char *fmt, return false; } +/* Look for a string within an argument */ +static bool find_print_string(const char *arg, const char *str, const char *end) +{ + const char *r; + + r = strstr(arg, str); + return r && r < end; +} + /* Return true if the argument pointer is safe */ static bool process_pointer(const char *fmt, int len, struct trace_event_call *call) { @@ -275,9 +284,17 @@ static bool process_pointer(const char * a = strchr(fmt, '&'); if ((a && (a < r)) || test_field(r, call)) return true; - } else if ((r = strstr(fmt, "__get_dynamic_array(")) && r < e) { + } else if (find_print_string(fmt, "__get_dynamic_array(", e)) { + return true; + } else if (find_print_string(fmt, "__get_rel_dynamic_array(", e)) { + return true; + } else if (find_print_string(fmt, "__get_dynamic_array_len(", e)) { + return true; + } else if (find_print_string(fmt, "__get_rel_dynamic_array_len(", e)) { + return true; + } else if (find_print_string(fmt, "__get_sockaddr(", e)) { return true; - } else if ((r = strstr(fmt, "__get_sockaddr(")) && r < e) { + } else if (find_print_string(fmt, "__get_rel_sockaddr(", e)) { return true; } return false;