[PATCH AUTOSEL 5.10 52/65] powerpc/secvar: fix refcount leak in format_show()

From: Sasha Levin
Date: Fri Apr 01 2022 - 11:28:52 EST


From: Hangyu Hua <hbh25y@xxxxxxxxx>

[ Upstream commit d601fd24e6964967f115f036a840f4f28488f63f ]

Refcount leak will happen when format_show returns failure in multiple
cases. Unified management of of_node_put can fix this problem.

Signed-off-by: Hangyu Hua <hbh25y@xxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220302021959.10959-1-hbh25y@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/powerpc/kernel/secvar-sysfs.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/secvar-sysfs.c b/arch/powerpc/kernel/secvar-sysfs.c
index a0a78aba2083..1ee4640a2641 100644
--- a/arch/powerpc/kernel/secvar-sysfs.c
+++ b/arch/powerpc/kernel/secvar-sysfs.c
@@ -26,15 +26,18 @@ static ssize_t format_show(struct kobject *kobj, struct kobj_attribute *attr,
const char *format;

node = of_find_compatible_node(NULL, NULL, "ibm,secvar-backend");
- if (!of_device_is_available(node))
- return -ENODEV;
+ if (!of_device_is_available(node)) {
+ rc = -ENODEV;
+ goto out;
+ }

rc = of_property_read_string(node, "format", &format);
if (rc)
- return rc;
+ goto out;

rc = sprintf(buf, "%s\n", format);

+out:
of_node_put(node);

return rc;
--
2.34.1