[PATCH 6/7] cpufreq: pmac32: fix possible object reference leak

From: Wen Yang
Date: Sun Mar 31 2019 - 21:38:34 EST


The call to of_find_node_by_name returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
./drivers/cpufreq/pmac32-cpufreq.c:557:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 552, but without a corresponding object release within this function.
./drivers/cpufreq/pmac32-cpufreq.c:569:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 552, but without a corresponding object release within this function.
./drivers/cpufreq/pmac32-cpufreq.c:598:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 587, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: linux-pm@xxxxxxxxxxxxxxx
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/cpufreq/pmac32-cpufreq.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/cpufreq/pmac32-cpufreq.c b/drivers/cpufreq/pmac32-cpufreq.c
index 52f0d91..9b4ce2e 100644
--- a/drivers/cpufreq/pmac32-cpufreq.c
+++ b/drivers/cpufreq/pmac32-cpufreq.c
@@ -552,6 +552,7 @@ static int pmac_cpufreq_init_7447A(struct device_node *cpunode)
volt_gpio_np = of_find_node_by_name(NULL, "cpu-vcore-select");
if (volt_gpio_np)
voltage_gpio = read_gpio(volt_gpio_np);
+ of_node_put(volt_gpio_np);
if (!voltage_gpio){
pr_err("missing cpu-vcore-select gpio\n");
return 1;
@@ -588,6 +589,7 @@ static int pmac_cpufreq_init_750FX(struct device_node *cpunode)
if (volt_gpio_np)
voltage_gpio = read_gpio(volt_gpio_np);

+ of_node_put(volt_gpio_np);
pvr = mfspr(SPRN_PVR);
has_cpu_l2lve = !((pvr & 0xf00) == 0x100);

--
2.9.5