From patchwork Sun Oct 5 21:46:03 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rickard Strandqvist X-Patchwork-Id: 5034931 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 3B56FC11AB for ; Mon, 6 Oct 2014 00:50:07 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4E67B201BC for ; Mon, 6 Oct 2014 00:50:06 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id CD90F20148 for ; Mon, 6 Oct 2014 00:50:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 313806E062; Sun, 5 Oct 2014 17:50:02 -0700 (PDT) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-la0-f41.google.com (mail-la0-f41.google.com [209.85.215.41]) by gabe.freedesktop.org (Postfix) with ESMTP id 0606E89364 for ; Sun, 5 Oct 2014 14:44:02 -0700 (PDT) Received: by mail-la0-f41.google.com with SMTP id pn19so3450921lab.0 for ; Sun, 05 Oct 2014 14:43:59 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=XlCXIpqsOzdg6HCvMFacsEMxAsAFPQgFtbb/ldm3ihs=; b=GruIz5P9WvE8QSS65FNPXOWl3ZH0RmaF75VEUnRcpJhpWpDRL8qmqIvNha3PA4Dffe k7Z2nv2fdZWUQLR5YcFRE/tSX1cTaDuraig4482Thh/WW08k9U7LRmLdrZixnLpm1yCd WraUNif1ZTWx+PJlr+Enx+XtEsPx1g0lNjbHtbcJxw6fNWgPcGn/qOp38Tu1CmAi9QZf 1nLzLrOh1IN5ABO18GAlyyU33jooXrsGDIKGnbQIEPxYuXJOM3lXY8H+jsJEoin2KPxi 4epitZc7MHobVu+xbBw/ZMKb9puoIunfoyl8yXIe3ODyhJA1ey7TedMS4A2uiU2p2gYd sRfA== X-Gm-Message-State: ALoCoQlFwaN0tR+hHEEN5h9RuxoZswKN5fsSkV2ULs+iWZXnaoSJoVmN8LcgcuHpOioGeU8AEBi2 X-Received: by 10.112.161.70 with SMTP id xq6mr19987380lbb.49.1412545439616; Sun, 05 Oct 2014 14:43:59 -0700 (PDT) Received: from localhost.localdomain (h-245-62.a218.priv.bahnhof.se. [85.24.245.62]) by mx.google.com with ESMTPSA id xs6sm5082579lbb.13.2014.10.05.14.43.58 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 05 Oct 2014 14:43:58 -0700 (PDT) From: Rickard Strandqvist To: David Airlie , dri-devel@lists.freedesktop.org Subject: [PATCH] gpu: drm: drm_dp_mst_topology.c: Fix improper use of strncat. Date: Sun, 5 Oct 2014 23:46:03 +0200 Message-Id: <1412545563-25411-1-git-send-email-rickard_strandqvist@spectrumdigital.se> X-Mailer: git-send-email 1.7.10.4 X-Mailman-Approved-At: Sun, 05 Oct 2014 17:50:01 -0700 Cc: linux-kernel@vger.kernel.org, Rickard Strandqvist X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP I have now eliminate the need to use the temporary string, and therefore also the use of strncat. And I think this code is clearer and more effective. Signed-off-by: Rickard Strandqvist --- drivers/gpu/drm/drm_dp_mst_topology.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index ac3c273..c3f6571 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -997,17 +997,18 @@ static void build_mst_prop_path(struct drm_dp_mst_port *port, struct drm_dp_mst_branch *mstb, char *proppath) { - int i; - char temp[8]; - snprintf(proppath, 255, "mst:%d", mstb->mgr->conn_base_id); + int i, len; + static const int proppath_len = 255; + memset(proppath, 0, proppath_len); + len = snprintf(proppath, proppath_len, "mst:%d", mstb->mgr->conn_base_id); for (i = 0; i < (mstb->lct - 1); i++) { int shift = (i % 2) ? 0 : 4; int port_num = mstb->rad[i / 2] >> shift; - snprintf(temp, 8, "-%d", port_num); - strncat(proppath, temp, 255); + len += snprintf(&proppath[(len < proppath_len ? len : 0)], + proppath_len - len, "-%d", port_num); } - snprintf(temp, 8, "-%d", port->port_num); - strncat(proppath, temp, 255); + snprintf(&proppath[(len < proppath_len ? len : 0)], proppath_len - len, + "-%d", port->port_num); } static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,