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 2D8A637A85D; Thu, 30 Jul 2026 15:20:46 +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=1785424847; cv=none; b=Yr9ILgw6ebhxRYRuMsgyA7QaO8JC2OmiH+YkOQN2b0yN0h6uVMx7LHapVHn8qyYdm+6UG6ugT0llV/SCvvd7uxRPAKMoLlxXKLqwU7kdMWOl4ln5CA/kwsgSnGmA/+PhtvpEMSieEbTJFI8Q1SAnLAxAdxO2XQdUu5iAwBmeR3k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424847; c=relaxed/simple; bh=ayRgtR7/N4umpoIBMjCaMXyDIlVnLMLmh4HzVXpYNI0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VjxX5HqHU6a2VEie3bOUwAtZruPMJZepcd7W/ZEtSV9+NL3KoeOMb8keVc6WeWmd31bN+QcIQmsDtWTTFvORJRIQ+1C9K7WV+nIiuM7Lb5OyJIVnvI9LD/bdUG3GzugLJ/5YTL9qs3/WS42HBTTTaylPvH88HsSfp+9H/XiqX7s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qy82RZr6; 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="qy82RZr6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 891831F000E9; Thu, 30 Jul 2026 15:20:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785424846; bh=PKy3HAtUIF8bNCHl8klchN+1kd7i9UrQ4PfmVIMX0VE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=qy82RZr68qXdO+lm9OrtSfoW8dUlycVFI0YcYKdp9Be7ZcFu52G88lphBNDjiks2V 6OgiVmpimhuERaEg4ARDbVz7bTXweVDqwHLs+Akuqa5aHUjhKh1IJS14MxU1AkcEFT PvD7PHGAie4H1IiJKPjUr2sO1axh6bsI+6GeCMno= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Doruk Tan Ozturk , Fernando Fernandez Mancera , Jakub Kicinski Subject: [PATCH 6.18 536/675] geneve: require CAP_NET_ADMIN in the device netns for changelink Date: Thu, 30 Jul 2026 16:14:26 +0200 Message-ID: <20260730141456.533833406@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Doruk Tan Ozturk commit 8efb8f8bbb353b8f2fdf4f37534c6d96c9f69e01 upstream. A tunnel changelink() operates on at most two netns, dev_net(dev) and the sticky underlay netns geneve->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 geneve->net can rewrite a geneve device whose underlay lives in geneve->net. geneve_changelink() applies the new configuration against geneve->net: geneve_link_config() and the geneve_quiesce()/geneve_unquiesce() pair reopen the underlay sockets in that netns (geneve_sock_add() uses geneve->net), so the same reasoning as the tunnel changelink series applies here. Gate geneve_changelink() with rtnl_dev_link_net_capable(), at the top of the op before any attribute is parsed, matching ipgre_changelink() and the rest of the "require CAP_NET_ADMIN in the device netns for changelink" series. Found by 0sec automated security-research tooling (https://0sec.ai). Fixes: 5b861f6baa3a ("geneve: add rtnl changelink support") Cc: stable@vger.kernel.org Signed-off-by: Doruk Tan Ozturk Reviewed-by: Fernando Fernandez Mancera Link: https://patch.msgid.link/20260716203500.70573-3-doruk@0sec.ai Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/geneve.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -1736,6 +1736,9 @@ static int geneve_changelink(struct net_ struct geneve_config cfg; int err; + if (!rtnl_dev_link_net_capable(dev, geneve->net)) + return -EPERM; + /* If the geneve device is configured for metadata (or externally * controlled, for example, OVS), then nothing can be changed. */