[PATCH 4.14 07/45] clocksource/drivers/timer-atmel-pit: Properly handle error cases

From: Greg Kroah-Hartman
Date: Thu Oct 11 2018 - 11:46:35 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>

commit 52bf4a900d9cede3eb14982d0f2c5e6db6d97cc3 upstream.

The smatch utility reports a possible leak:

smatch warnings:
drivers/clocksource/timer-atmel-pit.c:183 at91sam926x_pit_dt_init() warn: possible memory leak of 'data'

Ensure data is freed before exiting with an error.

Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/clocksource/timer-atmel-pit.c | 20 ++++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)

--- a/drivers/clocksource/timer-atmel-pit.c
+++ b/drivers/clocksource/timer-atmel-pit.c
@@ -180,26 +180,29 @@ static int __init at91sam926x_pit_dt_ini
data->base = of_iomap(node, 0);
if (!data->base) {
pr_err("Could not map PIT address\n");
- return -ENXIO;
+ ret = -ENXIO;
+ goto exit;
}

data->mck = of_clk_get(node, 0);
if (IS_ERR(data->mck)) {
pr_err("Unable to get mck clk\n");
- return PTR_ERR(data->mck);
+ ret = PTR_ERR(data->mck);
+ goto exit;
}

ret = clk_prepare_enable(data->mck);
if (ret) {
pr_err("Unable to enable mck\n");
- return ret;
+ goto exit;
}

/* Get the interrupts property */
data->irq = irq_of_parse_and_map(node, 0);
if (!data->irq) {
pr_err("Unable to get IRQ from DT\n");
- return -EINVAL;
+ ret = -EINVAL;
+ goto exit;
}

/*
@@ -227,7 +230,7 @@ static int __init at91sam926x_pit_dt_ini
ret = clocksource_register_hz(&data->clksrc, pit_rate);
if (ret) {
pr_err("Failed to register clocksource\n");
- return ret;
+ goto exit;
}

/* Set up irq handler */
@@ -236,7 +239,8 @@ static int __init at91sam926x_pit_dt_ini
"at91_tick", data);
if (ret) {
pr_err("Unable to setup IRQ\n");
- return ret;
+ clocksource_unregister(&data->clksrc);
+ goto exit;
}

/* Set up and register clockevents */
@@ -254,6 +258,10 @@ static int __init at91sam926x_pit_dt_ini
clockevents_register_device(&data->clkevt);

return 0;
+
+exit:
+ kfree(data);
+ return ret;
}
TIMER_OF_DECLARE(at91sam926x_pit, "atmel,at91sam9260-pit",
at91sam926x_pit_dt_init);