From patchwork Tue Nov 1 06:27:07 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 123033 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id A9E72B6F71 for ; Tue, 1 Nov 2011 17:33:02 +1100 (EST) Received: from localhost ([::1]:53006 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RL7pC-00049G-TD for incoming@patchwork.ozlabs.org; Tue, 01 Nov 2011 02:27:54 -0400 Received: from eggs.gnu.org ([140.186.70.92]:36626) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RL7of-0002Iu-K2 for qemu-devel@nongnu.org; Tue, 01 Nov 2011 02:27:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RL7oc-0004Hd-K9 for qemu-devel@nongnu.org; Tue, 01 Nov 2011 02:27:21 -0400 Received: from mtagate2.uk.ibm.com ([194.196.100.162]:59518) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RL7oc-0004HJ-8h for qemu-devel@nongnu.org; Tue, 01 Nov 2011 02:27:18 -0400 Received: from d06nrmr1707.portsmouth.uk.ibm.com (d06nrmr1707.portsmouth.uk.ibm.com [9.149.39.225]) by mtagate2.uk.ibm.com (8.13.1/8.13.1) with ESMTP id pA16RHKe014820 for ; Tue, 1 Nov 2011 06:27:17 GMT Received: from d06av11.portsmouth.uk.ibm.com (d06av11.portsmouth.uk.ibm.com [9.149.37.252]) by d06nrmr1707.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id pA16RHMK2154526 for ; Tue, 1 Nov 2011 06:27:17 GMT Received: from d06av11.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av11.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id pA16RGQf012601 for ; Tue, 1 Nov 2011 00:27:17 -0600 Received: from localhost (sig-9-78-68-221.uk.ibm.com [9.78.68.221]) by d06av11.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id pA16RGvb012598; Tue, 1 Nov 2011 00:27:16 -0600 From: Stefan Hajnoczi To: Date: Tue, 1 Nov 2011 06:27:07 +0000 Message-Id: <1320128830-25943-2-git-send-email-stefanha@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.7 In-Reply-To: <1320128830-25943-1-git-send-email-stefanha@linux.vnet.ibm.com> References: <1320128830-25943-1-git-send-email-stefanha@linux.vnet.ibm.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-Received-From: 194.196.100.162 Cc: Anthony Liguori , Stefan Hajnoczi , Luiz Capitulino Subject: [Qemu-devel] [PATCH 1/4] net: tap-linux: Fix unhelpful error message X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Luiz Capitulino I'm getting: could not configure /dev/net/tun (tap%d): Operation not permitted When the ioctl() fails, ifr.ifr_name will most likely not be overwritten. So we better only use it when ifname contains a string. Signed-off-by: Luiz Capitulino Signed-off-by: Stefan Hajnoczi --- net/tap-linux.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/net/tap-linux.c b/net/tap-linux.c index ff8cad0..41d581b 100644 --- a/net/tap-linux.c +++ b/net/tap-linux.c @@ -73,7 +73,11 @@ int tap_open(char *ifname, int ifname_size, int *vnet_hdr, int vnet_hdr_required pstrcpy(ifr.ifr_name, IFNAMSIZ, "tap%d"); ret = ioctl(fd, TUNSETIFF, (void *) &ifr); if (ret != 0) { - error_report("could not configure %s (%s): %m", PATH_NET_TUN, ifr.ifr_name); + if (ifname[0] != '\0') { + error_report("could not configure %s (%s): %m", PATH_NET_TUN, ifr.ifr_name); + } else { + error_report("could not configure %s: %m", PATH_NET_TUN); + } close(fd); return -1; }