From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cse.ust.hk (cssvr7.cse.ust.hk [143.89.41.157]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8968F22579E for ; Fri, 10 Oct 2025 06:35:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=143.89.41.157 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760078107; cv=pass; b=T5jXukpehBxf8tG33iL8ei5KlMoyAVeb9nCJphuOE6fY7d8qaG6sROOY1nUF8JUUb3+DvSF95iCLVsGv5Vel6qha6rAAiY/yQVTEGRUXsI2sVzKcOTqh1Zl1lPnHBPq3BND3orcFVVX3IFkheeFoc+fP/JSip/hMaivdnGvw49o= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760078107; c=relaxed/simple; bh=TfXKfGLIgdyqoC0vLmTK/YGBXyzqSeERAXzUxlk71To=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=CO5/474GoOcdZJcdK97dtt0X+Ddeg1rLQIVQ2gvr432KGvZIN2AufBCOvWh2l8/WARKEICA/tVWqmjSNhNUwiOZ4N/DCvkVvdohUDRWl6H0gf1aJsS/6AtRuW41TjBzadRvgJdEf1udtooim2xqXQi5+AG7HYY6dUk3u/2k7Gco= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=cse.ust.hk; spf=pass smtp.mailfrom=cse.ust.hk; dkim=pass (1024-bit key) header.d=cse.ust.hk header.i=@cse.ust.hk header.b=tCruLc/4; arc=pass smtp.client-ip=143.89.41.157 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=cse.ust.hk Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=cse.ust.hk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=cse.ust.hk header.i=@cse.ust.hk header.b="tCruLc/4" Received: from osx.local (ecs-119-8-240-33.compute.hwclouds-dns.com [119.8.240.33] (may be forged)) (authenticated bits=0) by cse.ust.hk (8.18.1/8.12.5) with ESMTPSA id 59A6YDcH2442651 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Fri, 10 Oct 2025 14:34:19 +0800 ARC-Seal: i=1; a=rsa-sha256; d=cse.ust.hk; s=arccse; t=1760078061; cv=none; b=iyh4uTH33qzmNtoDxOsdakGME2842mUtVmLWN51a/yKyinCxDIxVJmEYQYyEvSGUfOpn4XMNrZqWl6GIEYq4scd9w1p12keduyncuGV3aFV9GKEt3SdbRELp8apI7y+Re53ObPm6xwXldEMQcHmohYLtAQtDqILChXNjP4Mt9JE= ARC-Message-Signature: i=1; a=rsa-sha256; d=cse.ust.hk; s=arccse; t=1760078061; c=relaxed/relaxed; bh=mlixuZgziH+wjVJSfwbssxjlyT8K5O91PRYV9CIA+nk=; h=DKIM-Signature:Date:From:To:Subject:Message-ID:MIME-Version; b=w7ZddfkYI4L+Q2EOFZPOE1oRWTDGc8ECcVRnBW7X9/NS/p/rbaTS3++y+x/A0F6Yiw8m0vp/Ce30znLiocO52lMmm4ieL56OSjzHBLQBTFgY6ATAAvJ7kvKPE8/xrcBiKzTjL6hWwUTptGk7GnyGibF+A/ZyqFzi3128WdHyvY8= ARC-Authentication-Results: i=1; cse.ust.hk DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cse.ust.hk; s=cseusthk; t=1760078061; bh=mlixuZgziH+wjVJSfwbssxjlyT8K5O91PRYV9CIA+nk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tCruLc/4VmyGm6a9MIIxurcOVxwTx/Iel0VnEiWBcsHRHBLAazx26FnqJo9z+w1xl 5qvgVTWRNwFrdeAjjjFL2vNQzoj2ci1LvpaxZ/3SWZ8vJHpUR58JpBYz6YCGFs1nWP N8tTDQoClniJcd9twSb2tTt7cKNbKmV8UO23vjoM= Date: Fri, 10 Oct 2025 14:34:08 +0800 From: Shuhao Fu To: Frank Li Cc: Alexandre Belloni , linux-i3c@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] i3c: fix refcount inconsistency in i3c_master_register Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Env-From: sfual On Thu, Oct 09, 2025 at 12:17:11PM -0400, Frank Li wrote: > On Wed, Oct 08, 2025 at 03:27:09PM +0800, Shuhao Fu wrote: > > In `i3c_master_register`, a possible refcount inconsistency has been > > identified, causing possible resource leak. > > > > Function `of_node_get` increases the refcount of `parent->of_node`. If > > function `i3c_bus_init` fails, the function returns immediately without > > a corresponding decrease, resulting in an inconsistent refcounter. > > > > In this patch, an extra goto label is added to ensure the balance of > > refcount when `i3c_bus_init` fails. > > > > Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure") > > Signed-off-by: Shuhao Fu > > --- > > drivers/i3c/master.c | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c > > index d946db75d..9f4fe98d2 100644 > > --- a/drivers/i3c/master.c > > +++ b/drivers/i3c/master.c > > @@ -2885,7 +2885,7 @@ int i3c_master_register(struct i3c_master_controller *master, > > > > ret = i3c_bus_init(i3cbus, master->dev.of_node); > > if (ret) > > - return ret; > > + goto err_put_of_node; > > I think it'd better to set release function for master dev to release > of_node because of_node_put() also missed at i3c_master_unregister() > > you can refer drivers/base/platform.c > > Frank Do you mean that we should do `of_node_release` in `platform_device_release`, instead of respecting the refcounting via `of_node_put`? > > > > > device_initialize(&master->dev); > > dev_set_name(&master->dev, "i3c-%d", i3cbus->id); > > @@ -2973,6 +2973,9 @@ int i3c_master_register(struct i3c_master_controller *master, > > err_put_dev: > > put_device(&master->dev); > > > > +err_put_of_node: > > + of_node_put(master->dev.of_node); > > + > > return ret; > > } > > EXPORT_SYMBOL_GPL(i3c_master_register); > > -- > > 2.39.5 (Apple Git-154) > > > > > > -- > > linux-i3c mailing list > > linux-i3c@lists.infradead.org > > https://apc01.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.infradead.org%2Fmailman%2Flistinfo%2Flinux-i3c&data=05%7C02%7Csfual%40connect.ust.hk%7Cbfee3f910b654276330508de074f5750%7C6c1d415239d044ca88d9b8d6ddca0708%7C1%7C0%7C638956234525799989%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=aTeKcQJDC2Av%2FQ1MjtDuoOYrWJ6ZwhbjQbHs%2Fci90jw%3D&reserved=0