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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6D5A1C433EF for ; Wed, 13 Apr 2022 22:07:32 +0000 (UTC) Received: from localhost ([::1]:41646 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nel99-0002cF-FA for qemu-devel@archiver.kernel.org; Wed, 13 Apr 2022 18:07:31 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48774) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nel2b-0001Ja-Ny for qemu-devel@nongnu.org; Wed, 13 Apr 2022 18:00:45 -0400 Received: from smtp124.ord1d.emailsrvr.com ([184.106.54.124]:59879) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nel2Z-0004Ln-4O for qemu-devel@nongnu.org; Wed, 13 Apr 2022 18:00:45 -0400 X-Auth-ID: adeason@sinenomine.net Received: by smtp8.relay.ord1d.emailsrvr.com (Authenticated sender: adeason-AT-sinenomine.net) with ESMTPSA id D614AC01AB; Wed, 13 Apr 2022 18:00:16 -0400 (EDT) From: Andrew Deason To: qemu-devel@nongnu.org Subject: [PATCH v2 2/5] qga/commands-posix: Fix iface hw address detection Date: Wed, 13 Apr 2022 17:00:04 -0500 Message-Id: <20220413220007.14467-3-adeason@sinenomine.net> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20220413220007.14467-1-adeason@sinenomine.net> References: <20220413220007.14467-1-adeason@sinenomine.net> X-Classification-ID: 5647c629-c4e4-4626-ae9f-55e4ffbba697-3-1 Received-SPF: pass client-ip=184.106.54.124; envelope-from=adeason@sinenomine.net; helo=smtp124.ord1d.emailsrvr.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michael Roth , Andrew Deason , Michal Privoznik Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Since its introduction in commit 3424fc9f16a1 ("qemu-ga: add guest-network-get-interfaces command"), guest-network-get-interfaces seems to check if a given interface has a hardware address by checking 'ifa->ifa_flags & SIOCGIFHWADDR'. But ifa_flags is a field for IFF_* flags (IFF_UP, IFF_LOOPBACK, etc), and comparing it to an ioctl like SIOCGIFHWADDR doesn't make sense. On Linux, this isn't a big deal, since SIOCGIFHWADDR has so many bits set (0x8927), 'ifa->ifa_flags & SIOCGIFHWADDR' will usually have a nonzero result for any 'normal'-looking interfaces: anything with IFF_UP (0x1) or IFF_BROADCAST (0x2) set, as well as several less-common flags. This means we'll try to get the hardware address for most/all interfaces, even those that don't really have one (like the loopback device). For those interfaces, Linux just returns a hardware address of all zeroes. On Solaris, however, trying to get the hardware address for a loopback device returns an EADDRNOTAVAIL error. This causes us to return an error and the entire guest-network-get-interfaces call fails. Change this logic to always try to get the hardware address for each interface, and don't return an error if we fail to get it. Instead, just don't include the 'hardware-address' field in the result if we can't get the hardware address. Signed-off-by: Andrew Deason Reviewed-by: Michal Privoznik --- qga/commands-posix.c | 39 ++++++++++++++++++++++++--------------- 1 file changed, 24 insertions(+), 15 deletions(-) diff --git a/qga/commands-posix.c b/qga/commands-posix.c index e0feb5ffb5..bd0d67f674 100644 --- a/qga/commands-posix.c +++ b/qga/commands-posix.c @@ -2875,48 +2875,57 @@ GuestNetworkInterfaceList *qmp_guest_network_get_interfaces(Error **errp) info = guest_find_interface(head, ifa->ifa_name); if (!info) { info = g_malloc0(sizeof(*info)); info->name = g_strdup(ifa->ifa_name); QAPI_LIST_APPEND(tail, info); } - if (!info->has_hardware_address && ifa->ifa_flags & SIOCGIFHWADDR) { + if (!info->has_hardware_address) { /* we haven't obtained HW address yet */ sock = socket(PF_INET, SOCK_STREAM, 0); if (sock == -1) { error_setg_errno(errp, errno, "failed to create socket"); goto error; } memset(&ifr, 0, sizeof(ifr)); pstrcpy(ifr.ifr_name, IF_NAMESIZE, info->name); if (ioctl(sock, SIOCGIFHWADDR, &ifr) == -1) { - error_setg_errno(errp, errno, - "failed to get MAC address of %s", - ifa->ifa_name); - close(sock); - goto error; - } + /* + * We can't get the hw addr of this interface, but that's not a + * fatal error. Don't set info->hardware_address, but keep + * going. + */ + if (errno == EADDRNOTAVAIL) { + /* The interface doesn't have a hw addr (e.g. loopback). */ + g_debug("failed to get MAC address of %s: %s", + ifa->ifa_name, strerror(errno)); + } else{ + g_warning("failed to get MAC address of %s: %s", + ifa->ifa_name, strerror(errno)); + } - close(sock); - mac_addr = (unsigned char *) &ifr.ifr_hwaddr.sa_data; + } else { + mac_addr = (unsigned char *) &ifr.ifr_hwaddr.sa_data; - info->hardware_address = - g_strdup_printf("%02x:%02x:%02x:%02x:%02x:%02x", - (int) mac_addr[0], (int) mac_addr[1], - (int) mac_addr[2], (int) mac_addr[3], - (int) mac_addr[4], (int) mac_addr[5]); + info->hardware_address = + g_strdup_printf("%02x:%02x:%02x:%02x:%02x:%02x", + (int) mac_addr[0], (int) mac_addr[1], + (int) mac_addr[2], (int) mac_addr[3], + (int) mac_addr[4], (int) mac_addr[5]); - info->has_hardware_address = true; + info->has_hardware_address = true; + } + close(sock); } if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) { /* interface with IPv4 address */ p = &((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; if (!inet_ntop(AF_INET, p, addr4, sizeof(addr4))) { error_setg_errno(errp, errno, "inet_ntop failed"); goto error; } -- 2.11.0