[PATCH 1/5] powerpc/sparse: fix possible object reference leak

From: Wen Yang
Date: Thu Mar 21 2019 - 23:07:14 EST


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

Detected by coccinelle with the following warnings:
./arch/powerpc/platforms/pseries/pseries_energy.c:101:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 46, but without a corresponding object release within this function.
./arch/powerpc/platforms/pseries/pseries_energy.c:172:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 111, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
arch/powerpc/platforms/pseries/pseries_energy.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/pseries_energy.c b/arch/powerpc/platforms/pseries/pseries_energy.c
index 6ed2212..e3913e4 100644
--- a/arch/powerpc/platforms/pseries/pseries_energy.c
+++ b/arch/powerpc/platforms/pseries/pseries_energy.c
@@ -69,7 +69,7 @@ static u32 cpu_to_drc_index(int cpu)

of_read_drc_info_cell(&info, &value, &drc);
if (strncmp(drc.drc_type, "CPU", 3))
- goto err;
+ goto err_of_node_put;

if (thread_index < drc.last_drc_index)
break;
@@ -131,7 +131,7 @@ static int drc_index_to_cpu(u32 drc_index)

of_read_drc_info_cell(&info, &value, &drc);
if (strncmp(drc.drc_type, "CPU", 3))
- goto err;
+ goto err_of_node_put;

if (drc_index > drc.last_drc_index) {
cpu += drc.num_sequential_elems;
--
2.9.5