[PATCH AUTOSEL for 4.4 032/167] PowerCap: Fix an error code in powercap_register_zone()

Sasha Levin
2018-03-19T16:07:40Z

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit 216c4e9db4c9d1d2a382b42880442dc632cd47d9 ]

In the current code we accidentally return the successful result from
idr_alloc() instead of a negative error pointer. The caller is looking
for an error pointer and so it treats the returned value as a valid
pointer.

This one might be a bit serious because if it lets people get around the
kernel's protection for remapping NULL. I'm not sure.

Fixes: 75d2364ea0ca (PowerCap: Add class driver)
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
drivers/powercap/powercap_sys.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/powercap/powercap_sys.c b/drivers/powercap/powercap_sys.c
index 84419af16f77..fd12ccc11e26 100644
--- a/drivers/powercap/powercap_sys.c
+++ b/drivers/powercap/powercap_sys.c
@@ -538,6 +538,7 @@ struct powercap_zone *powercap_register_zone(

power_zone->id = result;
idr_init(&power_zone->idr);
+ result = -ENOMEM;
power_zone->name = kstrdup(name, GFP_KERNEL);
if (!power_zone->name)
goto err_name_alloc;
--
2.14.1