From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qt1-f202.google.com (mail-qt1-f202.google.com [209.85.160.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1DB7C3921CE for ; Thu, 2 Apr 2026 10:35:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775126123; cv=none; b=pNIqXPuEK7ZgyfYv3bXWO3kN328oUF7a/enqggycrXjhA3yjhcE3fYphcoFdqlZTx+k/+LHy68FrQkcf5XnoDNxQbLAEzy4zkYm3xbD6JxJ1mMMbekVAKLln347swCA7ItwxWeKJKoeL2qSGoWo76E6v9n/TJMefyixJl0DjR7U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775126123; c=relaxed/simple; bh=FQsFBMXFr9zfTGcchLu1aFoI2dk9QTFQtknsHXSnb1c=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=qzT0ozHUGkV0PmHF0z43owULOQpqPtsGG7FFhNGm/ZdUIWSumd45Bj/TtZ0Hpexp7p0gu9YZpLDDFn2QVcONr1/Lc/c+ZBesGUHBMAIHzQvBkv4sdJg46vOcfex+S5SX1EJFZrdDvbj6ecwwpleOpD7weQCGA1R1x+ylwV3YyHA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Dv0Z1hy2; arc=none smtp.client-ip=209.85.160.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Dv0Z1hy2" Received: by mail-qt1-f202.google.com with SMTP id d75a77b69052e-50b4b81c632so19553101cf.1 for ; Thu, 02 Apr 2026 03:35:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1775126121; x=1775730921; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=hTrYYWCDoops0RbC4qMtHcZwLDXHuLQzYz/4z22FWIM=; b=Dv0Z1hy2QtXROjDoMF/KWGifiFgpRGg0Nstp6g2fjSTGVRwhHJKQY2wQIcBR6VUmoe 8Dx44eqYx4cSyjNQD5qWeNu58gYnHEBxMZifPYreVJ4fNdm/601mzSgrbeBVoow45PZf 5kPnBLqib04LJyFatGRc8REbdTpDqvwWUte/JFvVOIvt+pdMmTXhXc0dV9TSpOkTCTKy l8DJ5TioSG5bfRac7rHV5vZB3MzuZIBkL7TePv4KUhveCuhXFA9u4q1UoBAra+2nMn1S FgIwD/3ORs16JkUbdTKhPfwYS01wzK2CQnYgANO5yh/2bIkRSHC8nmjqFDuUqWzhtNSl DMIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775126121; x=1775730921; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=hTrYYWCDoops0RbC4qMtHcZwLDXHuLQzYz/4z22FWIM=; b=UuVOZPVnOFAO0cSXsjEE1JGqKBz5kdyl1PooreWUuU0qvLTT0o1F3esu1dAp7fB0+z Uul3/na8Y5v7z/KD9sByFjnT2fRfEKB2dlJcxE0CEBOumvYPbLWdxWd8gbiqsNPtVeKw lYqTqADvncplsvWCb0q+ah06G/K1ghXEhY1Va23LSeI19BwkylsCuti8JXrQlcmdtWOZ 3cdANIwQRO92MJ6uxBTRGqXWLTgKjSbJxAwOs4OZ6jW3Iim+eC/ThiM5G0GkQxxYTSAm qKx1KkgJkgFFHL0XxhiMLWf01uEMvWpYRvjXtVIJYeJ42lz7WWBHGd8/IvOsp4lXZdl5 Dnxg== X-Forwarded-Encrypted: i=1; AJvYcCU563jvNcMFfBPcvnkUScJh8XhbQoLCW7VjXsKWNmjouTGfUDaXpMuFsC7mu3oI3IyYpRVnCjI=@vger.kernel.org X-Gm-Message-State: AOJu0YyXUS+NdwzjPNyh17BWxbosYzl6nhFucq0CAg2Ea04NIMpd2rSl QJPLPUiDLIPMCJOg56fnOahNQExGUiLGK25hNOQvvnGUkTLYSlTwVu/YTaLPiWrM1pvKi3kI5MC FI7ExarUUJYj1Dw== X-Received: from qtpb6.prod.google.com ([2002:ac8:6786:0:b0:50b:b6a0:30f8]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:ac8:5f14:0:b0:509:764:2efa with SMTP id d75a77b69052e-50d3bd4d777mr95913911cf.59.1775126120823; Thu, 02 Apr 2026 03:35:20 -0700 (PDT) Date: Thu, 2 Apr 2026 10:35:19 +0000 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.53.0.1185.g05d4b7b318-goog Message-ID: <20260402103519.1201565-1-edumazet@google.com> Subject: [PATCH v2 net] net: lapbether: handle NETDEV_PRE_TYPE_CHANGE From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet , syzbot+d8c285748fa7292580a9@syzkaller.appspotmail.com, Martin Schiller , linux-x25@vger.kernel.org Content-Type: text/plain; charset="UTF-8" lapbeth_data_transmit() expects the underlying device type to be ARPHRD_ETHER. Returning NOTIFY_BAD from lapbeth_device_event() makes sure bonding driver can not break this expectation. Fixes: 872254dd6b1f ("net/bonding: Enable bonding to enslave non ARPHRD_ETHER") Reported-by: syzbot+d8c285748fa7292580a9@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/69cd22a1.050a0220.70c3a.0002.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Cc: Martin Schiller Cc: linux-x25@vger.kernel.org --- v2: cache lapbeth_get_x25_dev() result in @lapbeth. make sure @lapbeth is set before returning NOTIFY_BAD. drivers/net/wan/lapbether.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/net/wan/lapbether.c b/drivers/net/wan/lapbether.c index f357a7ac70ac4756967730fa61c07258b4b3ac00..9861c99ea56c4efb03f22375b60f68665443e04d 100644 --- a/drivers/net/wan/lapbether.c +++ b/drivers/net/wan/lapbether.c @@ -446,33 +446,36 @@ static void lapbeth_free_device(struct lapbethdev *lapbeth) static int lapbeth_device_event(struct notifier_block *this, unsigned long event, void *ptr) { - struct lapbethdev *lapbeth; struct net_device *dev = netdev_notifier_info_to_dev(ptr); + struct lapbethdev *lapbeth; if (dev_net(dev) != &init_net) return NOTIFY_DONE; - if (!dev_is_ethdev(dev) && !lapbeth_get_x25_dev(dev)) + lapbeth = lapbeth_get_x25_dev(dev); + if (!dev_is_ethdev(dev) && !lapbeth) return NOTIFY_DONE; switch (event) { case NETDEV_UP: /* New ethernet device -> new LAPB interface */ - if (!lapbeth_get_x25_dev(dev)) + if (!lapbeth) lapbeth_new_device(dev); break; case NETDEV_GOING_DOWN: /* ethernet device closes -> close LAPB interface */ - lapbeth = lapbeth_get_x25_dev(dev); if (lapbeth) dev_close(lapbeth->axdev); break; case NETDEV_UNREGISTER: /* ethernet device disappears -> remove LAPB interface */ - lapbeth = lapbeth_get_x25_dev(dev); if (lapbeth) lapbeth_free_device(lapbeth); break; + case NETDEV_PRE_TYPE_CHANGE: + /* Our underlying device type must not change. */ + if (lapbeth) + return NOTIFY_BAD; } return NOTIFY_DONE; -- 2.53.0.1185.g05d4b7b318-goog