[PATCH 2/2] hw/sd/sd: Delay timer_new_ns() from init to realize to avoid memleaks

[Philippe Mathieu-Daudé]

In commit f3a508eb4e the Euler Robot reported calling timer_new()
in instance_init() can leak heap memory. The easier fix is to
delay the timer creation at instance realize(). Similarly move
timer_del() into a new instance unrealize() method.

This case was found with the following coccinelle script:

    @ match @
    identifier instance_init;
    typedef Object;
    identifier obj;
    expression val, scale;
    identifier clock_type, callback, opaque;
    position pos;
    @@
    static void instance_init(Object *obj)
    {
      <...
    (
      val = timer_new@pos(clock_type, scale, callback, opaque);
    |
      val = timer_new_ns@pos(clock_type, callback, opaque);
    |
      val = timer_new_us@pos(clock_type, callback, opaque);
    |
      val = timer_new_ms@pos(clock_type, callback, opaque);
    )
      ...>
    }

    @ script:python @
    f << match.instance_init;
    p << match.pos;
    @@
    print "check %s:%s:%s in %s()" % (p[0].file, p[0].line, p[0].column, f)

Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
---
Cc: Pan Nengyuan <pannengy...@huawei.com>
---
 hw/sd/sd.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/hw/sd/sd.c b/hw/sd/sd.c
index 71a9af09ab..d72cf3de2a 100644
--- a/hw/sd/sd.c
+++ b/hw/sd/sd.c
@@ -2058,14 +2058,12 @@ static void sd_instance_init(Object *obj)
     SDState *sd = SD_CARD(obj);
 
     sd->enable = true;
-    sd->ocr_power_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, sd_ocr_powerup, sd);
 }
 
 static void sd_instance_finalize(Object *obj)
 {
     SDState *sd = SD_CARD(obj);
 
-    timer_del(sd->ocr_power_timer);
     timer_free(sd->ocr_power_timer);
 }
 
@@ -2098,6 +2096,15 @@ static void sd_realize(DeviceState *dev, Error **errp)
         }
         blk_set_dev_ops(sd->blk, &sd_block_ops, sd);
     }
+
+    sd->ocr_power_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, sd_ocr_powerup, sd);
+}
+
+static void sd_unrealize(DeviceState *dev, Error **errp)
+{
+    SDState *sd = SD_CARD(dev);
+
+    timer_del(sd->ocr_power_timer);
 }
 
 static Property sd_properties[] = {
@@ -2118,6 +2125,7 @@ static void sd_class_init(ObjectClass *klass, void *data)
     SDCardClass *sc = SD_CARD_CLASS(klass);
 
     dc->realize = sd_realize;
+    dc->unrealize = sd_unrealize;
     device_class_set_props(dc, sd_properties);
     dc->vmsd = &sd_vmstate;
     dc->reset = sd_reset;
-- 
2.21.1