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 4465043E4BA; Tue, 16 Jun 2026 16:18:48 +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=1781626729; cv=none; b=a8DDmh2ldrjmAWtmvAq9jbm8qvvsu5IXrdX/d1vzvrPVN2kYuZhoH/jPYorjkYP5lWLgLXcfZzwMG/t02zvZslrPndknrDXqog2kmb25izhyFML1MWeFcGY2sFNcOwWyng9fNa2nA2IXsVZZrbY8NsOqGI/2o7DxD30PxoVn8LE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781626729; c=relaxed/simple; bh=whHCH0sO8r5zMQcDVCJM+IK8IP2r7yXiLo41A18/Nx0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=okj/A4sd9GR/hkVvzvIaGfi/iyfMRYxjEaCMKvDSq1tnPxC+TMTQ3eV37wqbT2aHpyTdYMHj80AoTiU1zWej/LVSGTENXicdulXf3wvXtCWmK9iTGDTD/BquXsX/+YiXYeIqiMxC3ltvX9KFJ2P/6ncWHIvxA9xruEYjNW9+dNQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BaItuaZC; 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="BaItuaZC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 470231F000E9; Tue, 16 Jun 2026 16:18:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781626728; bh=ZQS41QXP8InLel0W8jGMFBoluVtu83Pbc79E/8wgy+4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BaItuaZCcRhW4Gd6mg0ZzFVbdjDe4F/pRvOlVsRyjuQnjM4LJVOqOuEcXuv7d6cTC TkNGinZg112vqgXYZD/nG9t7nT3ILhMyIAxjyEBChkxEW1C7xQTXpmPhdqlWTpVmAY 00AsK1gnUeNTaBOQ91XNKXBd1kdNzPwg+Tg2dZ/s= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+f13c19f75e1097abd116@syzkaller.appspotmail.com, Eric Dumazet , Miquel Raynal , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.12 057/261] ieee802154: 6lowpan: only accept IPv6 packets in lowpan_xmit() Date: Tue, 16 Jun 2026 20:28:15 +0530 Message-ID: <20260616145047.799926376@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145044.869532709@linuxfoundation.org> References: <20260616145044.869532709@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: Eric Dumazet [ Upstream commit 3a5f3f7aff18bcc36a57839cf50cf0cc8de707f3 ] The aoe driver (or similar) generates a non-IPv6 packet (e.g., ETH_P_AOE) and queues it for transmission via dev_queue_xmit() on a 6LoWPAN interface (configured by the user or test case). Since the packet is not IPv6, the 6LoWPAN header_ops->create function (lowpan_header_create or header_create) returns early without initializing the lowpan_addr_info structure in the skb headroom. In the transmit function (lowpan_xmit), the driver calls lowpan_header (or setup_header) which unconditionally copies and uses the lowpan_addr_info from the headroom, which contains uninitialized data. Fix this by dropping non IPv6 packets. A similar fix is needed in net/bluetooth/6lowpan.c bt_xmit(). Fixes: 4dc315e267fe ("ieee802154: 6lowpan: move transmit functionality") Reported-by: syzbot+f13c19f75e1097abd116@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6a1fd763.278b5b03.2bcf39.0049.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Reviewed-by: Miquel Raynal Link: https://patch.msgid.link/20260603072955.4032221-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ieee802154/6lowpan/tx.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/ieee802154/6lowpan/tx.c b/net/ieee802154/6lowpan/tx.c index 0c07662b44c0ca..4df76ff50699ed 100644 --- a/net/ieee802154/6lowpan/tx.c +++ b/net/ieee802154/6lowpan/tx.c @@ -255,6 +255,11 @@ netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *ldev) pr_debug("package xmit\n"); + if (skb->protocol != htons(ETH_P_IPV6)) { + kfree_skb(skb); + return NET_XMIT_DROP; + } + WARN_ON_ONCE(skb->len > IPV6_MIN_MTU); /* We must take a copy of the skb before we modify/replace the ipv6 -- 2.53.0