From patchwork Thu Mar 21 23:41:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 10864595 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 64C5415AC for ; Thu, 21 Mar 2019 23:41:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3F1E82A55D for ; Thu, 21 Mar 2019 23:41:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 30CC82A55F; Thu, 21 Mar 2019 23:41:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 93C3C2A55D for ; Thu, 21 Mar 2019 23:41:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726374AbfCUXla (ORCPT ); Thu, 21 Mar 2019 19:41:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:47538 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725999AbfCUXla (ORCPT ); Thu, 21 Mar 2019 19:41:30 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 52D5D21900; Thu, 21 Mar 2019 23:41:29 +0000 (UTC) Date: Thu, 21 Mar 2019 19:41:27 -0400 From: Steven Rostedt To: Linux Trace Devel Cc: Slavomir Kaslev Subject: [PATCH] trace-cmd: Have tracecmd_msg_data_send() return zero on zero size Message-ID: <20190321194127.4ac47d99@gandalf.local.home> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: "Steven Rostedt (VMware)" If tracecmd_msg_data_send() is passed a size of zero, the loop is not entered, nothing is sent, but the ret variable is not initialized and garbage can be sent out. The option code can call this with a size of zero, which can cause an error report. Just don't do anything in this case, and return a success. Signed-off-by: Steven Rostedt (VMware) Reviewed-by: Slavomir Kaslev --- tracecmd/trace-msg.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tracecmd/trace-msg.c b/tracecmd/trace-msg.c index 51d0ac8b..382bd766 100644 --- a/tracecmd/trace-msg.c +++ b/tracecmd/trace-msg.c @@ -590,6 +590,10 @@ int tracecmd_msg_data_send(struct tracecmd_msg_handle *msg_handle, int ret; int count = 0; + /* Don't bother doing anything if there's nothing to do */ + if (!size) + return 0; + tracecmd_msg_init(MSG_SEND_DATA, &msg); msg.buf = malloc(MSG_MAX_DATA_LEN);