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 0392AC25B08 for ; Mon, 15 Aug 2022 22:19:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350602AbiHOWTH (ORCPT ); Mon, 15 Aug 2022 18:19:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345040AbiHOWOw (ORCPT ); Mon, 15 Aug 2022 18:14:52 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C0656745B; Mon, 15 Aug 2022 12:39:36 -0700 (PDT) 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 ams.source.kernel.org (Postfix) with ESMTPS id 7FB7AB81141; Mon, 15 Aug 2022 19:39:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9C6DC433D6; Mon, 15 Aug 2022 19:39:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660592372; bh=I0yTF2qYaIgcXNTD92Ug0VZKou04HKuY/Q+ASm9ai+4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oAoKuxrEFncwjGoLC0SB6MCda2sGQQ0suDsXkCdr7IutmHbIWikWatwGDMs7kP6Ud KujJKHGR2EPKIldOBo6eQlQUfY9jcOHIycpBaB4k+9+A784a3vnsXmAOWBCBkzB9I9 85hRSVKv2bDujP4EQrWA6GKRZ+XAhnZkgJfVkks0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Liang He , Bartosz Golaszewski , Sasha Levin Subject: [PATCH 5.18 0777/1095] gpio: gpiolib-of: Fix refcount bugs in of_mm_gpiochip_add_data() Date: Mon, 15 Aug 2022 20:02:56 +0200 Message-Id: <20220815180501.410976577@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220815180429.240518113@linuxfoundation.org> References: <20220815180429.240518113@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Liang He [ Upstream commit 5d07a692f9562f9c06e62cce369e9dd108173a0f ] We should use of_node_get() when a new reference of device_node is created. It is noted that the old reference stored in 'mm_gc->gc.of_node' should also be decreased. This patch is based on the fact that there is a call site in function 'qe_add_gpiochips()' of src file 'drivers\soc\fsl\qe\gpio.c'. In this function, of_mm_gpiochip_add_data() is contained in an iteration of for_each_compatible_node() which will automatically increase and decrease the refcount. So we need additional of_node_get() for the reference escape in of_mm_gpiochip_add_data(). Fixes: a19e3da5bc5f ("of/gpio: Kill of_gpio_chip and add members directly to gpio_chip") Signed-off-by: Liang He Signed-off-by: Bartosz Golaszewski Signed-off-by: Sasha Levin --- drivers/gpio/gpiolib-of.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index 6dec81b1f24b..5cabb9a9c272 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -861,7 +861,8 @@ int of_mm_gpiochip_add_data(struct device_node *np, if (mm_gc->save_regs) mm_gc->save_regs(mm_gc); - mm_gc->gc.of_node = np; + of_node_put(mm_gc->gc.of_node); + mm_gc->gc.of_node = of_node_get(np); ret = gpiochip_add_data(gc, data); if (ret) @@ -869,6 +870,7 @@ int of_mm_gpiochip_add_data(struct device_node *np, return 0; err2: + of_node_put(np); iounmap(mm_gc->regs); err1: kfree(gc->label); -- 2.35.1