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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BEA58C43219 for ; Mon, 7 Feb 2022 11:26:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236876AbiBGLZE (ORCPT ); Mon, 7 Feb 2022 06:25:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54038 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378393AbiBGLPu (ORCPT ); Mon, 7 Feb 2022 06:15:50 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9E3BCC03FEE8; Mon, 7 Feb 2022 03:15:31 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id DCA0C6113B; Mon, 7 Feb 2022 11:15:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C2460C004E1; Mon, 7 Feb 2022 11:15:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1644232530; bh=2OOCeYXrVO5I2xFEe1arKQB7R0jBUJ86hcpONKyUaUI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sBBVUiQIBmGhpxNd1dSxkMMFxIEwbxJWPhH286x66Qhhz3D+JTOmZnxqm/ZcpO/wM IxsxryPQIGTtEBlTufbDLj4r6L4MIrKawdQ++zVqQR9lEdmU5gs1HNmHzQHL7VmGIH 4D4inhjXVhBRn0sZ6iAxZX/PdBXxHJP0x56OtBA8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Marek=20Beh=C3=BAn?= , Andrew Lunn , Jakub Kicinski , Sasha Levin Subject: [PATCH 4.19 40/86] phylib: fix potential use-after-free Date: Mon, 7 Feb 2022 12:06:03 +0100 Message-Id: <20220207103758.845485398@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220207103757.550973048@linuxfoundation.org> References: <20220207103757.550973048@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: stable@vger.kernel.org From: Marek Behún [ Upstream commit cbda1b16687580d5beee38273f6241ae3725960c ] Commit bafbdd527d56 ("phylib: Add device reset GPIO support") added call to phy_device_reset(phydev) after the put_device() call in phy_detach(). The comment before the put_device() call says that the phydev might go away with put_device(). Fix potential use-after-free by calling phy_device_reset() before put_device(). Fixes: bafbdd527d56 ("phylib: Add device reset GPIO support") Signed-off-by: Marek Behún Reviewed-by: Andrew Lunn Link: https://lore.kernel.org/r/20220119162748.32418-1-kabel@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/phy/phy_device.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index b884b681d5c52..a03d0627efb06 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1166,6 +1166,9 @@ void phy_detach(struct phy_device *phydev) phydev->mdio.dev.driver == &genphy_driver.mdiodrv.driver) device_release_driver(&phydev->mdio.dev); + /* Assert the reset signal */ + phy_device_reset(phydev, 1); + /* * The phydev might go away on the put_device() below, so avoid * a use-after-free bug by reading the underlying bus first. @@ -1175,9 +1178,6 @@ void phy_detach(struct phy_device *phydev) put_device(&phydev->mdio.dev); if (ndev_owner != bus->owner) module_put(bus->owner); - - /* Assert the reset signal */ - phy_device_reset(phydev, 1); } EXPORT_SYMBOL(phy_detach); -- 2.34.1