From a2c14ff63e0e02e3c832385e523e9cc81301171c Mon Sep 17 00:00:00 2001 From: Ma Ke Date: Fri, 24 Apr 2026 09:10:13 +0800 Subject: [PATCH] power: supply: cpcap-battery: Fix missing nvmem_device_put() causing reference leak MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In cpcap_battery_detect_battery_type(), the reference to an nvmem device obtained via nvmem_device_find() is not released with nvmem_device_put() on the success or read-failure paths, causing a permanent reference leak. The driver’s retry logic on subsequent battery property reads can compound this leak, preventing the nvmem device from ever being freed. Found by code review. Signed-off-by: Ma Ke Cc: stable@vger.kernel.org Fixes: fd46821e85de ("power: supply: cpcap-battery: Add battery type auto detection for mapphone devices") Link: https://patch.msgid.link/20260424011013.879639-1-make24@iscas.ac.cn Signed-off-by: Sebastian Reichel --- drivers/power/supply/cpcap-battery.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c index 7b7bdce3162f..59c741993ef8 100644 --- a/drivers/power/supply/cpcap-battery.c +++ b/drivers/power/supply/cpcap-battery.c @@ -439,10 +439,13 @@ static void cpcap_battery_detect_battery_type(struct cpcap_battery_ddata *ddata) if (IS_ERR_OR_NULL(nvmem)) { ddata->check_nvmem = true; dev_info_once(ddata->dev, "Can not find battery nvmem device. Assuming generic lipo battery\n"); - } else if (nvmem_device_read(nvmem, 2, 1, &battery_id) < 0) { - battery_id = 0; - ddata->check_nvmem = true; - dev_warn(ddata->dev, "Can not read battery nvmem device. Assuming generic lipo battery\n"); + } else { + if (nvmem_device_read(nvmem, 2, 1, &battery_id) < 0) { + battery_id = 0; + ddata->check_nvmem = true; + dev_warn(ddata->dev, "Can not read battery nvmem device. Assuming generic lipo battery\n"); + } + nvmem_device_put(nvmem); } switch (battery_id) {