From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexandre Belloni , Lee Jones , Sasha Levin Subject: [PATCH 4.18 183/350] mfd: menelaus: Fix possible race condition and leak Date: Sun, 11 Nov 2018 14:20:47 -0800 Message-Id: <20181111221715.690691879@linuxfoundation.org> In-Reply-To: <20181111221707.043394111@linuxfoundation.org> References: <20181111221707.043394111@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexandre Belloni [ Upstream commit 9612f8f503804d2fd2f63aa6ba1e58bba4612d96 ] The IRQ work is added before the struct rtc is allocated and registered, but this struct is used in the IRQ handler. This may lead to a NULL pointer dereference. Switch to devm_rtc_allocate_device/rtc_register_device to allocate the rtc before calling menelaus_add_irq_work. Also, this solves a possible leak as the RTC is never released. Signed-off-by: Alexandre Belloni Signed-off-by: Lee Jones Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/mfd/menelaus.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/drivers/mfd/menelaus.c +++ b/drivers/mfd/menelaus.c @@ -1094,6 +1094,7 @@ static void menelaus_rtc_alarm_work(stru static inline void menelaus_rtc_init(struct menelaus_chip *m) { int alarm = (m->client->irq > 0); + int err; /* assume 32KDETEN pin is pulled high */ if (!(menelaus_read_reg(MENELAUS_OSC_CTRL) & 0x80)) { @@ -1101,6 +1102,12 @@ static inline void menelaus_rtc_init(str return; } + m->rtc = devm_rtc_allocate_device(&m->client->dev); + if (IS_ERR(m->rtc)) + return; + + m->rtc->ops = &menelaus_rtc_ops; + /* support RTC alarm; it can issue wakeups */ if (alarm) { if (menelaus_add_irq_work(MENELAUS_RTCALM_IRQ, @@ -1125,10 +1132,8 @@ static inline void menelaus_rtc_init(str menelaus_write_reg(MENELAUS_RTC_CTRL, m->rtc_control); } - m->rtc = rtc_device_register(DRIVER_NAME, - &m->client->dev, - &menelaus_rtc_ops, THIS_MODULE); - if (IS_ERR(m->rtc)) { + err = rtc_register_device(m->rtc); + if (err) { if (alarm) { menelaus_remove_irq_work(MENELAUS_RTCALM_IRQ); device_init_wakeup(&m->client->dev, 0);