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 8730F49D59C; Thu, 17 Sep 2026 18:50:57 +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=1789671059; cv=none; b=pmaHhNylMiiOnTClN1oluFrvjmOl48l2DspiOTQtqQRVnYbabj0P9JC/D8xhDPgDAdT0qzhxuObMpiFzQTXQGyuO4mNSW5fupm0R5qAGZ+rjUd+pUm8JHQSiZzZ/eAHU0KQXR8uQJic2nvblbXceLvZoQ5meDSfE0x1V39rQxuk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789671059; c=relaxed/simple; bh=payvh8koTNOxaOcI8T+oHiqahN1sdHum1YPrEd60fNw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lEpkDaH/8RWvAjAgp+jwJt543ltoSKMcd0d9HSXKJhgxQRlgRo5DAnLj0dK1h3J2PK5NAS6JyteeZeG3fhEAqF0vbuHqI92idIBcCmBmVfHisuKzkw5W9whVJ/PNudVytKKKDUvpdVDDB1fHdppw60GnFUGiQpezOe1MSGebAfk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=eNQNe7lI; 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="eNQNe7lI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 155001F000FF; Thu, 17 Sep 2026 18:50:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789671057; bh=WC5l+xPj400xbml6zJ44trr8BEQbDjVEp8R6JwLfd3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=eNQNe7lITSUt28nWoPrx0iSBK/tWlb2zURSMdfxHZ8rGb82QwMjvqTnqzH0FdgtFf MYYmY4MMXQ6qog27BwcVPQs3e09Hwy1/NTDYD5kYe7xRk44bMfU1jdkQVTjG6JGgFD rv5ZMun99P5WOcVZrl10LVVpxYakcAtO6vk0MiTo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vega , Zhiling Zou , Stefan Schmidt Subject: [PATCH 6.12 0855/1102] ieee802154: 6lowpan: fix NULL dereference in lowpan_newlink Date: Thu, 17 Sep 2026 16:13:18 +0100 Message-ID: <20260917151602.007473767@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151539.408551884@linuxfoundation.org> References: <20260917151539.408551884@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zhiling Zou commit bf79662bc85e820ac3b846e2f347da29fbf6ac95 upstream. TUNSETLINK allows a TUN device to change its link-layer type to ARPHRD_IEEE802154 without initializing ieee802154_ptr. lowpan_newlink() checks only the device type before dereferencing the pointer, so an RTM_NEWLINK request can trigger a NULL pointer dereference. Reject devices without ieee802154_ptr along with devices of the wrong type. Fixes: 51e0e5d8124e ("ieee802154: 6lowpan: remove multiple lowpan per wpan support") Cc: stable@vger.kernel.org Reported-by: Vega Signed-off-by: Zhiling Zou Link: https://lore.kernel.org/0b715da69bd15a86ddc47dad5cf12da648211050.1787997209.git.zhilinz@nebusec.ai Signed-off-by: Stefan Schmidt Signed-off-by: Greg Kroah-Hartman --- net/ieee802154/6lowpan/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/ieee802154/6lowpan/core.c +++ b/net/ieee802154/6lowpan/core.c @@ -146,7 +146,7 @@ static int lowpan_newlink(struct net *sr wdev = dev_get_by_index(dev_net(ldev), nla_get_u32(tb[IFLA_LINK])); if (!wdev) return -ENODEV; - if (wdev->type != ARPHRD_IEEE802154) { + if (wdev->type != ARPHRD_IEEE802154 || !wdev->ieee802154_ptr) { dev_put(wdev); return -EINVAL; }