From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A5A032DFA29 for ; Tue, 15 Apr 2025 15:15:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744730155; cv=none; b=t7K6Rd7Qh3XCJdnXVA6RMl+D08vP0YJ2fP5033RRF9R0omicQiqBG+wq1+t2sGkyhAAtKFThk6+aL1jtezArYZSO+rvX3DzBUMbPTvG8+i7QkVniSFbKX0S154IvHjYOyIFfGh4rhFs+UAHn1PHQmdmEVAd97dLKKiG+W9Iancw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744730155; c=relaxed/simple; bh=WodU4GOELVP+iaKVHqKuf6yNIusD0gRistMcBTFBnKk=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=ggfTxZe3pE/y3yPA91ueEzufX+HdasJMpLSiWVqCuRGM1lSZhwr89txMYnca+aKmgBVuLz8rtOInTzi9zimUKpFJSU9Q+Edaa+GVcSznth0sAwEEYMIPKbnqiMP3qoGgLFpD2dxN/zYYaNzBe6jeErH5jHr2FaBQQnYUNULoruk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IINH8G3/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IINH8G3/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C809C4CEEB; Tue, 15 Apr 2025 15:15:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1744730155; bh=WodU4GOELVP+iaKVHqKuf6yNIusD0gRistMcBTFBnKk=; h=From:To:Cc:Subject:Date:From; b=IINH8G3/K9fdxmlmCSgqGc91/XqeDBESmF0jlsk6cDbWqJ2x21MpWGd2TcXBTKZCo XkTygSFaaar6nIzZwiVlMLnqX9lw0jY4srovKtwvt4hXGje0t3TOY+X+e9yjMHGBwc Iwx6DX1qoeppr5PpFZ72Vx+I2ic7Ff0uJ17kUPDWO72NToG51Od7MXgkaSTlsXZS/P DbBVMrZuR3aYJsRWaqdvithoUWzP727eQ2+c9/qxb+Xlpvi4XEd0EeNhpVc5S6gDTE unuiTXOEX8MQ3UTlD+f3ZUoVahFta4lHrsK6Wm4qNGIAKpg1oA3b4igElLEvSSho0r T27U9sm8I5EyQ== From: Jakub Kicinski To: davem@davemloft.net Cc: netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, Jakub Kicinski , syzbot+de1c7d68a10e3f123bdd@syzkaller.appspotmail.com, sdf@fomichev.me, kuniyu@amazon.com Subject: [PATCH net] net: don't try to ops lock uninitialized devs Date: Tue, 15 Apr 2025 08:15:52 -0700 Message-ID: <20250415151552.768373-1-kuba@kernel.org> X-Mailer: git-send-email 2.49.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit We need to be careful when operating on dev while in rtnl_create_link(). Some devices (vxlan) initialize netdev_ops in ->newlink, so later on. Avoid using netdev_lock_ops(), the device isn't registered so we cannot legally call its ops or generate any notifications for it. netdev_ops_assert_locked_or_invisible() is safe to use, it checks registration status first. Reported-by: syzbot+de1c7d68a10e3f123bdd@syzkaller.appspotmail.com Fixes: 04efcee6ef8d ("net: hold instance lock during NETDEV_CHANGE") Signed-off-by: Jakub Kicinski --- CC: sdf@fomichev.me CC: kuniyu@amazon.com I wasn't sure whether Kuniyuki is going to send this or he's waiting for me to send.. so let me send and get this off my tracking list :) --- net/core/dev.c | 2 ++ net/core/rtnetlink.c | 5 +---- 2 files changed, 3 insertions(+), 4 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 03d20a98f8b7..c5e15701cfb3 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1572,6 +1572,8 @@ EXPORT_SYMBOL(netdev_features_change); void netif_state_change(struct net_device *dev) { + netdev_ops_assert_locked_or_invisible(dev); + if (dev->flags & IFF_UP) { struct netdev_notifier_change_info change_info = { .info.dev = dev, diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 38526210b8fd..bb624fc6ca8a 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -3677,11 +3677,8 @@ struct net_device *rtnl_create_link(struct net *net, const char *ifname, nla_len(tb[IFLA_BROADCAST])); if (tb[IFLA_TXQLEN]) dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]); - if (tb[IFLA_OPERSTATE]) { - netdev_lock_ops(dev); + if (tb[IFLA_OPERSTATE]) set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE])); - netdev_unlock_ops(dev); - } if (tb[IFLA_LINKMODE]) dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]); if (tb[IFLA_GROUP]) -- 2.49.0