From: PanNengyuan <pannengyuan@huawei.com>
This avoid a memory leak when qom-set is called to set throttle_group
limits, here is an easy way to reproduce:
1. run qemu-iotests as follow and check the result with asan:
./check -qcow2 184
Following is the asan output backtrack:
Direct leak of 912 byte(s) in 3 object(s) allocated from:
#0 0xffff8d7ab3c3 in __interceptor_calloc (/lib64/libasan.so.4+0xd33c3)
#1 0xffff8d4c31cb in g_malloc0 (/lib64/libglib-2.0.so.0+0x571cb)
#2 0x190c857 in qobject_input_start_struct /mnt/sdc/qemu-master/qemu-4.2.0-rc0/qapi/qobject-input-visitor.c:295
#3 0x19070df in visit_start_struct /mnt/sdc/qemu-master/qemu-4.2.0-rc0/qapi/qapi-visit-core.c:49
#4 0x1948b87 in visit_type_ThrottleLimits qapi/qapi-visit-block-core.c:3759
#5 0x17e4aa3 in throttle_group_set_limits /mnt/sdc/qemu-master/qemu-4.2.0-rc0/block/throttle-groups.c:900
#6 0x1650eff in object_property_set /mnt/sdc/qemu-master/qemu-4.2.0-rc0/qom/object.c:1272
#7 0x1658517 in object_property_set_qobject /mnt/sdc/qemu-master/qemu-4.2.0-rc0/qom/qom-qobject.c:26
#8 0x15880bb in qmp_qom_set /mnt/sdc/qemu-master/qemu-4.2.0-rc0/qom/qom-qmp-cmds.c:74
#9 0x157e3e3 in qmp_marshal_qom_set qapi/qapi-commands-qom.c:154
Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: PanNengyuan <pannengyuan@huawei.com>
---
Changes v2 to v1:
- remove unused var 'arg' (suggested by Alberto Garcia)
---
block/throttle-groups.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/block/throttle-groups.c b/block/throttle-groups.c
index 77014c7..37695b0 100644
--- a/block/throttle-groups.c
+++ b/block/throttle-groups.c
@@ -893,8 +893,7 @@ static void throttle_group_set_limits(Object *obj, Visitor *v,
{
ThrottleGroup *tg = THROTTLE_GROUP(obj);
ThrottleConfig cfg;
- ThrottleLimits arg = { 0 };
- ThrottleLimits *argp = &arg;
+ ThrottleLimits *argp;
Error *local_err = NULL;
visit_type_ThrottleLimits(v, name, &argp, &local_err);
@@ -912,6 +911,7 @@ static void throttle_group_set_limits(Object *obj, Visitor *v,
unlock:
qemu_mutex_unlock(&tg->lock);
ret:
+ qapi_free_ThrottleLimits(argp);
error_propagate(errp, local_err);
return;
}
--
2.7.2.windows.1