From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4EA33C433F5 for ; Mon, 1 Nov 2021 09:22:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3AEAC61177 for ; Mon, 1 Nov 2021 09:22:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232466AbhKAJYj (ORCPT ); Mon, 1 Nov 2021 05:24:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:59154 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232329AbhKAJWp (ORCPT ); Mon, 1 Nov 2021 05:22:45 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C0683610D2; Mon, 1 Nov 2021 09:20:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1635758406; bh=KWLZ198wCx5EPHjJSx32Ieau92M15KuKnZkKEnZNU6M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Goo7HoXUJxhyVd/jn76nYcMQGaXY7kjB4jZGcWvZThPhAgXAS2pe99vG87D0gZ+Ic PW7QNMIYoEzl4V8b2m5P5n3JX9BT5rFoUmfEevNlkl1L9amG/ONlVwcxeH+yLoh5eH 9+ipv0AD0VTG8YnIH2Hl1gUtLAwMsxidPVoAdwZ0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yanfei Xu , Pavel Skripkin , Jakub Kicinski Subject: [PATCH 4.14 10/25] Revert "net: mdiobus: Fix memory leak in __mdiobus_register" Date: Mon, 1 Nov 2021 10:17:22 +0100 Message-Id: <20211101082449.464714831@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211101082447.070493993@linuxfoundation.org> References: <20211101082447.070493993@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pavel Skripkin commit 10eff1f5788b6ffac212c254e2f3666219576889 upstream. This reverts commit ab609f25d19858513919369ff3d9a63c02cd9e2e. This patch is correct in the sense that we _should_ call device_put() in case of device_register() failure, but the problem in this code is more vast. We need to set bus->state to UNMDIOBUS_REGISTERED before calling device_register() to correctly release the device in mdiobus_free(). This patch prevents us from doing it, since in case of device_register() failure put_device() will be called 2 times and it will cause UAF or something else. Also, Reported-by: tag in revered commit was wrong, since syzbot reported different leak in same function. Link: https://lore.kernel.org/netdev/20210928092657.GI2048@kadam/ Acked-by: Yanfei Xu Signed-off-by: Pavel Skripkin Link: https://lore.kernel.org/r/f12fb1faa4eccf0f355788225335eb4309ff2599.1633024062.git.paskripkin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/phy/mdio_bus.c | 1 - 1 file changed, 1 deletion(-) --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -354,7 +354,6 @@ int __mdiobus_register(struct mii_bus *b err = device_register(&bus->dev); if (err) { pr_err("mii_bus %s failed to register\n", bus->id); - put_device(&bus->dev); return -EINVAL; }