[PATCH 5.15 127/135] memory: samsung: exynos5422-dmc: Fix refcount leak in of_get_dram_timings

Greg Kroah-Hartman
2022-06-27T11:45:34Z

From: Miaoqian Lin <linmq006@gmail.com>

commit 1332661e09304b7b8e84e5edc11811ba08d12abe upstream.

of_parse_phandle() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
This function doesn't call of_node_put() in some error paths.
To unify the structure, Add put_node label and goto it on errors.

Fixes: 6e7674c3c6df ("memory: Add DMC driver for Exynos5422")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://lore.kernel.org/r/20220602041721.64348-1-linmq006@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/memory/samsung/exynos5422-dmc.c | 29 ++++++++++++++++++-----------
1 file changed, 18 insertions(+), 11 deletions(-)

--- a/drivers/memory/samsung/exynos5422-dmc.c
+++ b/drivers/memory/samsung/exynos5422-dmc.c
@@ -1187,33 +1187,39 @@ static int of_get_dram_timings(struct ex

dmc->timing_row = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
sizeof(u32), GFP_KERNEL);
- if (!dmc->timing_row)
- return -ENOMEM;
+ if (!dmc->timing_row) {
+ ret = -ENOMEM;
+ goto put_node;
+ }

dmc->timing_data = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
sizeof(u32), GFP_KERNEL);
- if (!dmc->timing_data)
- return -ENOMEM;
+ if (!dmc->timing_data) {
+ ret = -ENOMEM;
+ goto put_node;
+ }

dmc->timing_power = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
sizeof(u32), GFP_KERNEL);
- if (!dmc->timing_power)
- return -ENOMEM;
+ if (!dmc->timing_power) {
+ ret = -ENOMEM;
+ goto put_node;
+ }

dmc->timings = of_lpddr3_get_ddr_timings(np_ddr, dmc->dev,
DDR_TYPE_LPDDR3,
&dmc->timings_arr_size);
if (!dmc->timings) {
- of_node_put(np_ddr);
dev_warn(dmc->dev, "could not get timings from DT\n");
- return -EINVAL;
+ ret = -EINVAL;
+ goto put_node;
}

dmc->min_tck = of_lpddr3_get_min_tck(np_ddr, dmc->dev);
if (!dmc->min_tck) {
- of_node_put(np_ddr);
dev_warn(dmc->dev, "could not get tck from DT\n");
- return -EINVAL;
+ ret = -EINVAL;
+ goto put_node;
}

/* Sorted array of OPPs with frequency ascending */
@@ -1227,13 +1233,14 @@ static int of_get_dram_timings(struct ex
clk_period_ps);
}

- of_node_put(np_ddr);

/* Take the highest frequency's timings as 'bypass' */
dmc->bypass_timing_row = dmc->timing_row[idx - 1];
dmc->bypass_timing_data = dmc->timing_data[idx - 1];
dmc->bypass_timing_power = dmc->timing_power[idx - 1];

+put_node:
+ of_node_put(np_ddr);
return ret;
}