From patchwork Wed Mar 2 18:49:44 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 18473 X-Patchwork-Delegate: sw@simonwunderlich.de Return-Path: X-Original-To: patchwork@open-mesh.org Delivered-To: patchwork@open-mesh.org Received: from diktynna.open-mesh.org (localhost [IPv6:::1]) by diktynna.open-mesh.org (Postfix) with ESMTP id B050784499; Wed, 2 Mar 2022 19:49:59 +0100 (CET) Received: from dvalin.narfation.org (dvalin.narfation.org [IPv6:2a00:17d8:100::8b1]) by diktynna.open-mesh.org (Postfix) with ESMTPS id 2AB9C8001C for ; Wed, 2 Mar 2022 19:49:55 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=narfation.org; s=20121; t=1646246994; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=68B4uCg0jgF4vh/DBlT6MDT+JLmCPlWhaTKMCs2/zwQ=; b=YhVk0TFwBs+2z7Np8A+7YTs/SZqnRcVIKkBKb23dXeOJiBRKkNyyXidWuisCbxcMJ21tbf hQAzeDnHIrXDXX1NU8LJHp7pFIDefLV31xXPAWiyZxP9T6KEy8vN0BYrf+uTK9XVe7cTOa 4ybMbnyyW9NK1SC8bbX2wgmSnfCUI3g= From: Sven Eckelmann To: b.a.t.m.a.n@lists.open-mesh.org Cc: Sven Eckelmann Subject: [PATCH maint 1/3] batman-adv: Request iflink once in batadv-on-batadv check Date: Wed, 2 Mar 2022 19:49:44 +0100 Message-Id: <20220302184946.414934-1-sven@narfation.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 ARC-Authentication-Results: i=1; diktynna.open-mesh.org; dkim=pass header.d=narfation.org header.s=20121 header.b=YhVk0TFw; dmarc=pass (policy=none) header.from=narfation.org; spf=pass (diktynna.open-mesh.org: domain of sven@narfation.org designates 2a00:17d8:100::8b1 as permitted sender) smtp.mailfrom=sven@narfation.org ARC-Seal: i=1; s=20121; d=open-mesh.org; t=1646246995; a=rsa-sha256; cv=none; b=O38qfK7Jat4zt03lFZj9qi6TRuaDw9qY0xd1O8mEE3s16mjQBFh+WXb4va06R0NTAGpkOf nVhg+/7ghyYq9tiZqwBV8Ie2ZPWu2yhR2EpZhNdRs4/tOhy9HwYyDTSGIzSVAT3WyknLK0 GO6Z1Vx27pCrv5wivGfRtVy1kNtAqXo= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1646246995; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding:dkim-signature; bh=68B4uCg0jgF4vh/DBlT6MDT+JLmCPlWhaTKMCs2/zwQ=; b=JPQYUY91deD4CG04Iq2u0q2wT+ZsXxA8aBL1qPhS0LwisTYyS3bpgtLVQhY5YdQuf9SLMv 453SFe4AvTr/R38J0Gg22O0OXZT2oZM2IArjLIjH1HEiOb4uSpSOOldIt3zvSbmLoJT9EH gT5gVl6VXAOlIftAl89qw5tj199LMDU= Message-ID-Hash: 7S3FIFQG6MMGI64C5EYX3FN3ONVXJA3T X-Message-ID-Hash: 7S3FIFQG6MMGI64C5EYX3FN3ONVXJA3T X-MailFrom: sven@narfation.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-b.a.t.m.a.n.lists.open-mesh.org-0; header-match-b.a.t.m.a.n.lists.open-mesh.org-1; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header X-Mailman-Version: 3.2.1 Precedence: list Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: There is no need to call dev_get_iflink multiple times for the same net_device in batadv_is_on_batman_iface. And since some of the .ndo_get_iflink callbacks are dynamic (for example via RCUs like in vxcan_get_iflink), it could easily happen that the returned values are not stable. The pre-checks before __dev_get_by_index are then of course bogus. Fixes: 3d48811b27f5 ("batman-adv: prevent using any virtual device created on batman-adv as hard-interface") Signed-off-by: Sven Eckelmann --- net/batman-adv/hard-interface.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index 59d19097..774a26c5 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -149,22 +149,23 @@ static bool batadv_is_on_batman_iface(const struct net_device *net_dev) struct net *net = dev_net(net_dev); struct net_device *parent_dev; struct net *parent_net; + int iflink; bool ret; /* check if this is a batman-adv mesh interface */ if (batadv_softif_is_valid(net_dev)) return true; + iflink = dev_get_iflink(net_dev); + /* no more parents..stop recursion */ - if (dev_get_iflink(net_dev) == 0 || - dev_get_iflink(net_dev) == net_dev->ifindex) + if (iflink == 0 || iflink == net_dev->ifindex) return false; parent_net = batadv_getlink_net(net_dev, net); /* recurse over the parent device */ - parent_dev = __dev_get_by_index((struct net *)parent_net, - dev_get_iflink(net_dev)); + parent_dev = __dev_get_by_index((struct net *)parent_net, iflink); /* if we got a NULL parent_dev there is something broken.. */ if (!parent_dev) { pr_err("Cannot find parent device\n");