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 X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C4394ECDE44 for ; Wed, 31 Oct 2018 23:07:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8AA0E20843 for ; Wed, 31 Oct 2018 23:07:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="0/NmBIq8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8AA0E20843 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728683AbeKAIHN (ORCPT ); Thu, 1 Nov 2018 04:07:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:54748 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728646AbeKAIHM (ORCPT ); Thu, 1 Nov 2018 04:07:12 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E4F5720830; Wed, 31 Oct 2018 23:07:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541027221; bh=lnwAYRnij7/dG5MTGCKc2ZqWr+tKNp1FUnymCKTx1sA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0/NmBIq82DBSqNrZat8bCPjoyolxmhXumE3r3QncJJBZj3rHX0PEfpkEm7gl6H85e 3VBKbEMhC3Wuu1K/0YkDdjbQgmyjY24OO1t3/jItfSfL9SKjhQD3tSLZmCG1spTBz6 4HDNcjBfJK6P1abksyw6arRsCCwrDLRe+YNiM3OM= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Johan Hovold , Andrew Lunn , Giuseppe Cavallaro , Alexandre Torgue , Jose Abreu , "David S . Miller" , Rob Herring , Sasha Levin Subject: [PATCH AUTOSEL 4.19 087/146] net: stmmac: dwmac-sun8i: fix OF child-node lookup Date: Wed, 31 Oct 2018 19:04:42 -0400 Message-Id: <20181031230541.28822-87-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181031230541.28822-1-sashal@kernel.org> References: <20181031230541.28822-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Johan Hovold [ Upstream commit ac63043d8cb5503c7e0fe110f947eacf2663804e ] Use the new of_get_compatible_child() helper to lookup the mdio-internal child node instead of using of_find_compatible_node(), which searches the entire tree from a given start node and thus can return an unrelated (i.e. non-child) node. This also addresses a potential use-after-free (e.g. after probe deferral) as the tree-wide helper drops a reference to its first argument (i.e. the mdio-mux node). Fortunately, this was inadvertently balanced by a failure to drop the mdio-mux reference after lookup. While at it, also fix the related mdio-internal- and phy-node reference leaks. Fixes: 634db83b8265 ("net: stmmac: dwmac-sun8i: Handle integrated/external MDIOs") Tested-by: Corentin Labbe Cc: Andrew Lunn Cc: Giuseppe Cavallaro Cc: Alexandre Torgue Cc: Jose Abreu Cc: David S. Miller Signed-off-by: Johan Hovold Signed-off-by: Rob Herring Signed-off-by: Sasha Levin --- drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c index f9a61f90cfbc..0f660af01a4b 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c @@ -714,8 +714,9 @@ static int get_ephy_nodes(struct stmmac_priv *priv) return -ENODEV; } - mdio_internal = of_find_compatible_node(mdio_mux, NULL, + mdio_internal = of_get_compatible_child(mdio_mux, "allwinner,sun8i-h3-mdio-internal"); + of_node_put(mdio_mux); if (!mdio_internal) { dev_err(priv->device, "Cannot get internal_mdio node\n"); return -ENODEV; @@ -729,13 +730,20 @@ static int get_ephy_nodes(struct stmmac_priv *priv) gmac->rst_ephy = of_reset_control_get_exclusive(iphynode, NULL); if (IS_ERR(gmac->rst_ephy)) { ret = PTR_ERR(gmac->rst_ephy); - if (ret == -EPROBE_DEFER) + if (ret == -EPROBE_DEFER) { + of_node_put(iphynode); + of_node_put(mdio_internal); return ret; + } continue; } dev_info(priv->device, "Found internal PHY node\n"); + of_node_put(iphynode); + of_node_put(mdio_internal); return 0; } + + of_node_put(mdio_internal); return -ENODEV; } -- 2.17.1