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 01BB4C433EF for ; Thu, 30 Sep 2021 17:50:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D5A1561A07 for ; Thu, 30 Sep 2021 17:50:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352852AbhI3RwM (ORCPT ); Thu, 30 Sep 2021 13:52:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55410 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352839AbhI3RwK (ORCPT ); Thu, 30 Sep 2021 13:52:10 -0400 Received: from mail-lf1-x135.google.com (mail-lf1-x135.google.com [IPv6:2a00:1450:4864:20::135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8F9DC06176A; Thu, 30 Sep 2021 10:50:27 -0700 (PDT) Received: by mail-lf1-x135.google.com with SMTP id x27so28236759lfa.9; Thu, 30 Sep 2021 10:50:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=WbMGoSeIG8Nre7YI94HB+1s+5OyVO37vI/FQasjDNY0=; b=qKckho3veE14jzoQZa3FHX5ehyczkirMrSzEPpck72OtAr3vB9PyWSrebSRG9I/sHP 6IsrpzAOdLNiEudtcudInoxpEGgzbYB33JMUki6jD9wXa/qa689vM8U8HfVP69AJGFzd eFswiR4DEymO4lgUpvyk9smlkFfWLENrJvza3tWKrfpWI8hTcNmyO0oXJAuNqMfIj5FJ YPvJRxm2kHaW0kZezFrmKGfUtWSG5CzIwo701Pe4Y3LOV3EEZEvTTlInFIpA7mZxQEZA RNGwB0Ey6aa4NH+bBMZs+KVFO2xgrgx4yj7s31jeiPVutjV6P/j4VyPhqiNWy5hVCPRa F4IQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=WbMGoSeIG8Nre7YI94HB+1s+5OyVO37vI/FQasjDNY0=; b=5UE9e/4Qa57fHv4xKEFv2juW4QGHb18JxdKtihZgOgLwrHwPEy90WLdamsPpeEqcCP g9doasuvfFJek0G55MAZGcNRn0ITbd9ZThCzUPyTzzxwnQ38KZWM1be+XIZQP2ufaCRv oUPkNyzaFnUT7GZ9SH7WT4cE9/ksM5/7Cuno8idPvj+O5BCSnQDSk5mrPCO2WFJwpYph kLci+OAF2maV5sWNcDlScjWmgtSamDFvylf9EGl3rQiMrt8ctjvXL7qSWwJOAaeuC99K MNeNk3WEeO+VfCKhi1vE7Lp0rYV8JMPJVOIKtLN4rRnIbmXG4BnsAMcWktR3g8Vypa1x QyQQ== X-Gm-Message-State: AOAM5305tBPDRCNof88UMxdOmNIBNygnQormNWhcs9UfvF7ciXm7CkOS 997nFqMwbIyCOq5ReAKSdb4= X-Google-Smtp-Source: ABdhPJzld8V0K1gmh+IgO8cfbtKL/xWokjolndUwXEnW/wfwaR9oljJXtjxvR61kmj0h8nuNQxqJoA== X-Received: by 2002:a05:6512:b0c:: with SMTP id w12mr568372lfu.240.1633024225985; Thu, 30 Sep 2021 10:50:25 -0700 (PDT) Received: from localhost.localdomain ([217.117.245.149]) by smtp.gmail.com with ESMTPSA id q6sm485712lfn.170.2021.09.30.10.50.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Sep 2021 10:50:25 -0700 (PDT) From: Pavel Skripkin To: andrew@lunn.ch, hkallweit1@gmail.com, linux@armlinux.org.uk, davem@davemloft.net, kuba@kernel.org, buytenh@marvell.com, afleming@freescale.com Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Pavel Skripkin , Yanfei Xu Subject: [PATCH v4 1/2] Revert "net: mdiobus: Fix memory leak in __mdiobus_register" Date: Thu, 30 Sep 2021 20:49:42 +0300 Message-Id: X-Mailer: git-send-email 2.33.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- Chnages in v4: No changes Changes in v3: CC Yanfei -> Acked-by Yanfei Changes in v2: Added this revert --- drivers/net/phy/mdio_bus.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index 6f4b4e5df639..53f034fc2ef7 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -537,7 +537,6 @@ int __mdiobus_register(struct mii_bus *bus, struct module *owner) err = device_register(&bus->dev); if (err) { pr_err("mii_bus %s failed to register\n", bus->id); - put_device(&bus->dev); return -EINVAL; } -- 2.33.0