From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E195B44AB91; Tue, 21 Jul 2026 21:44:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784670291; cv=none; b=DK499fc3P2VtBf6C3ExZdPt/mzk+b+3Bv3fnOA1RAodbRbtvotN7CICrcusvyC44YL5CKd8CQdd+ubL1sMzEIU1v6132BsqhG8e/zt2JcB8jdzCT+Z/QfVP/AAdknVXvurZ7JvTAk0a53o1YBq0ntX4UEIH4wKcDTAhWItvZjPI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784670291; c=relaxed/simple; bh=KMCFBDRhpG7k8eM7EMPbWh0rMGYX08yIbYCyNta9eiw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nDko4iyXF2gszXTVgGBQUkD+noIaJNubItluZDJOoSVbcdvj7zFV2Z1zaQusPVSHULur46eIE2nK4WkYOALHiTliE5MDTveK5wpQW8HQ+zhwqkr9LTFhJz95AOsP+zSR244TL94z73JmAyKGO8Ksv52a6Xxq74PZTy5KN9BfykY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Jco01lXW; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Jco01lXW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53D511F000E9; Tue, 21 Jul 2026 21:44:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784670290; bh=QZJqudk5J8LoV5jb2S8nJ8G6D2mdr2TxUq3lKJ8z3Es=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Jco01lXW9u0TTIACwcRowuxdAJtmznnZtuCFHWHYq47+6ljwiHXTBmb5DEJJj0shR C8DsGkGKIF/KBip998Yejt2k3akcrxKVdbLMHFffN65r0XbKfGmzDKoBz/OVnzyHUv 9Z4SkybF9OAgH2nH+gcQNJ+PEsbpALsgrnvWolE0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Maoyi Xie , Nicolas Dichtel , Kuniyuki Iwashima , Jakub Kicinski Subject: [PATCH 6.1 0876/1067] net: sit: require CAP_NET_ADMIN in the device netns for changelink Date: Tue, 21 Jul 2026 17:24:37 +0200 Message-ID: <20260721152444.129415047@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152424.521567757@linuxfoundation.org> References: <20260721152424.521567757@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Maoyi Xie commit 27ccb68e7cccead5d8c611665a45d23032d468b3 upstream. ipip6_changelink() operates on at most two netns, dev_net(dev) and the tunnel link netns t->net. They differ once the device is created in or moved to a netns other than the one the request runs in. The rtnl changelink path checks CAP_NET_ADMIN only against dev_net(dev), so a caller privileged there but not in t->net can rewrite a tunnel that lives in t->net. Gate ipip6_changelink() on rtnl_dev_link_net_capable() at its top, before any attribute is parsed. sit was the one tunnel type not covered by the recent series that added this check to the other changelink() handlers. Fixes: 5e6700b3bf98 ("sit: add support of x-netns") Link: https://lore.kernel.org/netdev/20260612085941.3158249-1-maoyixie.tju@gmail.com/ Cc: stable@vger.kernel.org Signed-off-by: Maoyi Xie Reviewed-by: Nicolas Dichtel Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260618070817.3378283-1-maoyixie.tju@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/ipv6/sit.c | 3 +++ 1 file changed, 3 insertions(+) --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -1615,6 +1615,9 @@ static int ipip6_changelink(struct net_d __u32 fwmark = t->fwmark; int err; + if (!rtnl_dev_link_net_capable(dev, net)) + return -EPERM; + if (dev == sitn->fb_tunnel_dev) return -EINVAL;