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 1EB55C433EF for ; Mon, 1 Nov 2021 09:28:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE4EE61391 for ; Mon, 1 Nov 2021 09:28:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232513AbhKAJbO (ORCPT ); Mon, 1 Nov 2021 05:31:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:36830 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232834AbhKAJ2D (ORCPT ); Mon, 1 Nov 2021 05:28:03 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 41C8A611C5; Mon, 1 Nov 2021 09:22:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1635758557; bh=dsvR+jMv+1KcQ65oX45GBozaLFymzzrKSk9REQN0lDI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0s2xKr7bS/wZ/kyuIWaVxE71ArlfMOdmt6uYpWlKrYFn8Fq2/2VrSOAHJIGsdPapz Bd5gZ9pCQ7aJmMyLMdzmIGK0o539dojCXqn7YZdN8WCziguxARCGDezdT068wht9tf Fw63UO5c+QBp8NQvg5DFtaXapYIym0mSLgyIjOWc= 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 5.4 13/51] Revert "net: mdiobus: Fix memory leak in __mdiobus_register" Date: Mon, 1 Nov 2021 10:17:17 +0100 Message-Id: <20211101082503.703704540@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211101082500.203657870@linuxfoundation.org> References: <20211101082500.203657870@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 @@ -395,7 +395,6 @@ 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; }