2020-11-14 04:22:18

by Youling Tang

Subject: [PATCH] rtc: Fix memleak in sun6i_rtc_clk_init

When rtc->base or rtc->int_osc or rtc->losc or rtc->ext_losc is NULL,
we should free clk_data and rtc before the function returns to prevent
memleak.

Signed-off-by: Youling Tang <[email protected]>
---
drivers/rtc/rtc-sun6i.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c
index e2b8b15..84ff1e6 100644
--- a/drivers/rtc/rtc-sun6i.c
+++ b/drivers/rtc/rtc-sun6i.c
@@ -272,7 +272,7 @@ static void __init sun6i_rtc_clk_init(struct device_node *node,
300000000);
if (IS_ERR(rtc->int_osc)) {
pr_crit("Couldn't register the internal oscillator\n");
- return;
+ goto err;
}

parents[0] = clk_hw_get_name(rtc->int_osc);
@@ -290,7 +290,7 @@ static void __init sun6i_rtc_clk_init(struct device_node *node,
rtc->losc = clk_register(NULL, &rtc->hw);
if (IS_ERR(rtc->losc)) {
pr_crit("Couldn't register the LOSC clock\n");
- return;
+ goto err;
}

of_property_read_string_index(node, "clock-output-names", 1,
@@ -301,7 +301,7 @@ static void __init sun6i_rtc_clk_init(struct device_node *node,
&rtc->lock);
if (IS_ERR(rtc->ext_losc)) {
pr_crit("Couldn't register the LOSC external gate\n");
- return;
+ goto err;
}

clk_data->num = 2;
@@ -316,6 +316,7 @@ static void __init sun6i_rtc_clk_init(struct device_node *node,

err:
kfree(clk_data);
+ kfree(rtc);
}

static const struct sun6i_rtc_clk_data sun6i_a31_rtc_data = {
--
2.1.0

2020-11-14 22:20:35

by Alexandre Belloni

Subject: Re: [PATCH] rtc: Fix memleak in sun6i_rtc_clk_init

Hi,

Thank you for the patch.

On 14/11/2020 12:18:21+0800, Youling Tang wrote:
> When rtc->base or rtc->int_osc or rtc->losc or rtc->ext_losc is NULL,
> we should free clk_data and rtc before the function returns to prevent
> memleak.
>

I think this is fixed by 28d211919e422f58c1e6c900e5810eee4f1ce4c8 in my
branch:
https://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux.git/commit/?id=28d211919e422f58c1e6c900e5810eee4f1ce4c8

--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com