From nobody Sun Feb 8 10:49:17 2026 Received: from cstnet.cn (smtp81.cstnet.cn [159.226.251.81]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 772C02E7BB5; Sat, 25 Oct 2025 14:24:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.81 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761402259; cv=none; b=qGfOfaXAo0pSF2iNa+jFzqoSKxPv0yHy52Dik+Tzqfq6zHz4zGZrDAPgEAcGfW7V0ATLPY3gFbsNgx5YyBZskiU2DMtZXRXqfxC+2+/KTtUBhTy6jOYT6UxkVfMV1luHwrCNmrz/12ee96z2FkBuyAj1RlTb4xNQI6bw2Y2zQUY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761402259; c=relaxed/simple; bh=+bv92ATdBBjbTgiNEpB2pAzl8R6jUHhFTnx/H0dV3d8=; h=From:To:Cc:Subject:Date:Message-Id; b=Vnqn31J2LgvZ/2lc+LYYn9Xbnz1od1BrkknN27cZtbNYX3VZ1CtIkjdbuueiL3BJk+38Co62Gcz2QJIe0GkjIsy6ls9HMsOEdv+vQAKGnKedoOOuIxVYK6QRoKebXbrAN2Ajx4+i9fpzQunth628qa1bvxjsyiienaS8uNtAlkU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.81 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from localhost.localdomain (unknown [202.112.113.212]) by APP-03 (Coremail) with SMTP id rQCowAA3vWF53fxoIJeYAA--.6133S2; Sat, 25 Oct 2025 22:24:01 +0800 (CST) From: Ma Ke To: lee@kernel.org, suzuki.poulose@arm.com, broonie@kernel.org, mdf@kernel.org, wsa@kernel.org Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Ma Ke , stable@vger.kernel.org Subject: [PATCH] drivers: Fix reference leak in altr_sysmgr_regmap_lookup_by_phandle() Date: Sat, 25 Oct 2025 22:23:52 +0800 Message-Id: <20251025142352.25475-1-make24@iscas.ac.cn> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: rQCowAA3vWF53fxoIJeYAA--.6133S2 X-Coremail-Antispam: 1UD129KBjvJXoW7Zw4DXF48KrWUZFyrAr43Wrg_yoW8WF4rpr WUGa4Ykr9rG3W8Ww409w1UAFWakr48C3yS93yjk3sY93Zaq34fJFyjgayjv3s0yFyUGF4U tFsFy348AF4UGw7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9l14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r1I6r4UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Cr1j6rxdM28EF7xvwVC2z280aVCY1x0267AKxVWxJr 0_GcWlnxkEFVAIw20F6cxK64vIFxWle2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xv F2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r 4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I 648v4I1lc7CjxVAaw2AFwI0_Jw0_GFylc2xSY4AK67AK6ry5MxAIw28IcxkI7VAKI48JMx C20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAF wI0_JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20x vE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw20EY4v2 0xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxV WUJVW8JbIYCTnIWIevJa73UjIFyTuYvjfUYXdjDUUUU X-CM-SenderInfo: ppdnvj2u6l2u1dvotugofq/ Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" altr_sysmgr_regmap_lookup_by_phandle() utilizes driver_find_device_by_of_node() which internally calls driver_find_device() to locate the matching device. driver_find_device() increments the ref count of the found device by calling get_device(), but altr_sysmgr_regmap_lookup_by_phandle() fails to call put_device() to decrement the reference count before returning. This results in a reference count leak of the device, which may prevent the device from being properly released and cause a memory leak. Found by code review. Cc: stable@vger.kernel.org Fixes: cfba5de9b99f ("drivers: Introduce device lookup variants by of_node") Signed-off-by: Ma Ke --- drivers/mfd/altera-sysmgr.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/mfd/altera-sysmgr.c b/drivers/mfd/altera-sysmgr.c index fb5f988e61f3..c6c763fb7bbe 100644 --- a/drivers/mfd/altera-sysmgr.c +++ b/drivers/mfd/altera-sysmgr.c @@ -98,6 +98,7 @@ struct regmap *altr_sysmgr_regmap_lookup_by_phandle(struc= t device_node *np, struct device *dev; struct altr_sysmgr *sysmgr; struct device_node *sysmgr_np; + struct regmap *regmap; =20 if (property) sysmgr_np =3D of_parse_phandle(np, property, 0); @@ -116,8 +117,10 @@ struct regmap *altr_sysmgr_regmap_lookup_by_phandle(st= ruct device_node *np, return ERR_PTR(-EPROBE_DEFER); =20 sysmgr =3D dev_get_drvdata(dev); + regmap =3D sysmgr->regmap; + put_device(dev); =20 - return sysmgr->regmap; + return regmap; } EXPORT_SYMBOL_GPL(altr_sysmgr_regmap_lookup_by_phandle); =20 --=20 2.17.1