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 406A8C433EF for ; Sat, 9 Oct 2021 04:20:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E54F60F9C for ; Sat, 9 Oct 2021 04:20:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229736AbhJIEWu (ORCPT ); Sat, 9 Oct 2021 00:22:50 -0400 Received: from zg8tmty1ljiyny4xntqumjca.icoremail.net ([165.227.154.27]:56504 "HELO zg8tmty1ljiyny4xntqumjca.icoremail.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S229480AbhJIEWr (ORCPT ); Sat, 9 Oct 2021 00:22:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fudan.edu.cn; s=dkim; h=Received:From:To:Cc:Subject:Date: Message-Id:MIME-Version:Content-Transfer-Encoding; bh=djcJNMrGEx 11DVeXfstEyaEscPLXu5hozbJu0q4CIqU=; b=tW3DT98Y/QG1bzhwtNp/ra8uo9 Wxaa2l2HM3rczHiQ8lc4PvZ1UYti6+NOCW8R0N6R5XhfoJc87rGWOdBvR0uBOxEW l/WxbBN6V6gpxzqO6H0JD4MbPujy8rvVav3lfyer8hLJZHLQcf4JcQfMnWPwJSXF XUj9OTAUsElweQ/wY= Received: from localhost.localdomain (unknown [10.102.225.147]) by app2 (Coremail) with SMTP id XQUFCgBXim6OGGFhruAAAA--.1394S4; Sat, 09 Oct 2021 12:20:40 +0800 (CST) From: Xin Xiong To: Ulf Hansson , linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org Cc: yuanxzhang@fudan.edu.cn, Xin Xiong , Xiyu Yang , Xin Tan Subject: [PATCH v4] drivers/mmc: fix reference count leaks in moxart_probe Date: Sat, 9 Oct 2021 12:19:18 +0800 Message-Id: <20211009041918.28419-1-xiongx18@fudan.edu.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: XQUFCgBXim6OGGFhruAAAA--.1394S4 X-Coremail-Antispam: 1UD129KBjvJXoW7WF1xJF4Utw4rKFyUXr4xJFb_yoW8tr4xpF 48Cr9xKrWUtr4agF4xCa1kXF18Zr1Fyw4akrZ8u3s7A34UJFnrC34kG3W0qF95JryrXa9Y gF15tF1ruFW8JFJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvS14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4U JVW0owA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC 0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUGVWUXwAv7VC2z280aVAFwI0_Jr0_Gr 1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IE rcIFxwCY02Avz4vE-syl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2 IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v2 6r126r1DMIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2 IY6xkF7I0E14v26r1j6r4UMIIF0xvE42xK8VAvwI8IcIk0rVWrZr1j6s0DMIIF0xvEx4A2 jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Jr0_GrUvcSsGvfC2KfnxnUUI43 ZEXa7VU1c4S5UUUUU== X-CM-SenderInfo: arytiiqsuqiimz6i3vldqovvfxof0/1tbiARAIEFKp41whwwABsu Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The issue happens in several error handling paths on two refcounted object related to the object "host" (dma_chan_rx, dma_chan_tx). In these paths, the function forgets to decrement one or both objects' reference count increased earlier by dma_request_chan(), causing reference count leaks. Fix it by balancing the refcounts of both objects in some error handling paths. In correspondence with the changes in moxart_probe(), IS_ERR() is replaced with IS_ERR_OR_NULL() in moxart_remove() as well. Signed-off-by: Xin Xiong Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan --- drivers/mmc/host/moxart-mmc.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c index 6c9d38132..7b9fcef49 100644 --- a/drivers/mmc/host/moxart-mmc.c +++ b/drivers/mmc/host/moxart-mmc.c @@ -621,6 +621,14 @@ static int moxart_probe(struct platform_device *pdev) ret = -EPROBE_DEFER; goto out; } + if (!IS_ERR(host->dma_chan_tx)) { + dma_release_channel(host->dma_chan_tx); + host->dma_chan_tx = NULL; + } + if (!IS_ERR(host->dma_chan_rx)) { + dma_release_channel(host->dma_chan_rx); + host->dma_chan_rx = NULL; + } dev_dbg(dev, "PIO mode transfer enabled\n"); host->have_dma = false; } else { @@ -675,6 +683,10 @@ static int moxart_probe(struct platform_device *pdev) return 0; out: + if (!IS_ERR_OR_NULL(host->dma_chan_tx)) + dma_release_channel(host->dma_chan_tx); + if (!IS_ERR_OR_NULL(host->dma_chan_rx)) + dma_release_channel(host->dma_chan_rx); if (mmc) mmc_free_host(mmc); return ret; @@ -687,9 +699,9 @@ static int moxart_remove(struct platform_device *pdev) dev_set_drvdata(&pdev->dev, NULL); - if (!IS_ERR(host->dma_chan_tx)) + if (!IS_ERR_OR_NULL(host->dma_chan_tx)) dma_release_channel(host->dma_chan_tx); - if (!IS_ERR(host->dma_chan_rx)) + if (!IS_ERR_OR_NULL(host->dma_chan_rx)) dma_release_channel(host->dma_chan_rx); mmc_remove_host(mmc); mmc_free_host(mmc); -- 2.25.1