From nobody Tue Jun 23 16:17:33 2026 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 20422C433EF for ; Wed, 2 Mar 2022 13:31:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242235AbiCBNbn (ORCPT ); Wed, 2 Mar 2022 08:31:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45892 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237407AbiCBNbl (ORCPT ); Wed, 2 Mar 2022 08:31:41 -0500 Received: from zg8tmty1ljiyny4xntqumjca.icoremail.net (zg8tmty1ljiyny4xntqumjca.icoremail.net [165.227.154.27]) by lindbergh.monkeyblade.net (Postfix) with SMTP id 90AC9BA76B for ; Wed, 2 Mar 2022 05:30:54 -0800 (PST) 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=iMaVXwk3iG rh60WLRmIvGc+VdwFYNW0mHH3SCrZ7WO8=; b=v/G8PjMjWUihvkpKtwrOY3Yq7k Xmd9dva8SrKjgb4bH0MCUdvRzJ2tbak1EKdW0fWs3sFcGiiKaOOc5H7g4Zq+hL2y 3AJv2Lg+QdwDSwIZ/ofJzc9MZdAi41RDdS7heG60XJKxoDs0mc9NBDeCDQOas7Cq sRWTbqtBXQNju7Ce4= Received: from localhost.localdomain (unknown [10.102.225.84]) by app1 (Coremail) with SMTP id XAUFCgCnvMBWcR9iqJhcCg--.35820S4; Wed, 02 Mar 2022 21:30:03 +0800 (CST) From: Xin Xiong To: Tudor Ambarus , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Nicolas Ferre , Alexandre Belloni , Claudiu Beznea , Boris Brezillon , linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: yuanxzhang@fudan.edu.cn, Xin Xiong , Xiyu Yang , Xin Tan Subject: [PATCH v3] mtd: rawnand: atmel: fix refcount issue in atmel_nand_controller_init Date: Wed, 2 Mar 2022 21:27:59 +0800 Message-Id: <20220302132758.3820-1-xiongx18@fudan.edu.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: XAUFCgCnvMBWcR9iqJhcCg--.35820S4 X-Coremail-Antispam: 1UD129KBjvJXoW7Zw47ZF4DGrW7uF4rZw47urg_yoW8trykpF WUJFW3ZFWUtFs3ZF12kayxuF1rZ3WkJFyUG3yqqa4xZ3ZxXa4jkryYqr10vFyUCFyfuF17 ZF47t3W8CF1UGFUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9K14x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1lnxkEFVAIw20F6cxK64vIFxWle2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xv F2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r 4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I 648v4I1lFIxGxcIEc7CjxVA2Y2ka0xkIwI1lc2xSY4AK6svPMxAIw28IcxkI7VAKI48JMx C20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAF wI0_JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20x vE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v2 0xvaj40_WFyUJVCq3wCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14 v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUOrcfUUUUU X-CM-SenderInfo: arytiiqsuqiimz6i3vldqovvfxof0/1tbiAQ4NEFKp48tIbgAAsn Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The reference counting issue happens in several error handling paths on a refcounted object "nc->dmac". In these paths, the function simply returns the error code, forgetting to balance the reference count of "nc->dmac", increased earlier by dma_request_channel(), which may cause refcount leaks. Fix it by decrementing the refcount of specific object in those error paths. Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver") Co-developed-by: Xiyu Yang Signed-off-by: Xiyu Yang Co-developed-by: Xin Tan Signed-off-by: Xin Tan Signed-off-by: Xin Xiong --- V2 -> V3: Removed redundant lines V1 -> V2: Rewrited the error handling block --- drivers/mtd/nand/raw/atmel/nand-controller.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nan= d/raw/atmel/nand-controller.c index f3276ee9e4fe..3dc4a4bacde5 100644 --- a/drivers/mtd/nand/raw/atmel/nand-controller.c +++ b/drivers/mtd/nand/raw/atmel/nand-controller.c @@ -2060,13 +2060,15 @@ static int atmel_nand_controller_init(struct atmel_= nand_controller *nc, nc->mck =3D of_clk_get(dev->parent->of_node, 0); if (IS_ERR(nc->mck)) { dev_err(dev, "Failed to retrieve MCK clk\n"); - return PTR_ERR(nc->mck); + ret =3D PTR_ERR(nc->mck); + goto out_release_dma; } =20 np =3D of_parse_phandle(dev->parent->of_node, "atmel,smc", 0); if (!np) { dev_err(dev, "Missing or invalid atmel,smc property\n"); - return -EINVAL; + ret =3D -EINVAL; + goto out_release_dma; } =20 nc->smc =3D syscon_node_to_regmap(np); @@ -2074,10 +2076,16 @@ static int atmel_nand_controller_init(struct atmel_= nand_controller *nc, if (IS_ERR(nc->smc)) { ret =3D PTR_ERR(nc->smc); dev_err(dev, "Could not get SMC regmap (err =3D %d)\n", ret); - return ret; + goto out_release_dma; } =20 return 0; + +out_release_dma: + if (nc->caps->has_dma && !atmel_nand_avoid_dma && nc->dmac) + dma_release_channel(nc->dmac); + + return ret; } =20 static int --=20 2.25.1