[patch] xenfb: fix potential memory leak

Joe Jin
2011-01-07T10:22:10Z

Hi,

This patch fix potential memory leak when xenfb connect backend failed.
Thanks for Ian's review and comments.

Signed-off-by: Joe Jin <joe.jin@oracle.com>
Tested-by: Gurudas Pai <gurudas.pai@oracle.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>

---
xen-fbfront.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/video/xen-fbfront.c b/drivers/video/xen-fbfront.c
index dc72563..953334a 100644
--- a/drivers/video/xen-fbfront.c
+++ b/drivers/video/xen-fbfront.c
@@ -561,26 +561,24 @@ static void xenfb_init_shared_page(struct xenfb_info *info,
static int xenfb_connect_backend(struct xenbus_device *dev,
struct xenfb_info *info)
{
- int ret, evtchn;
+ int ret, evtchn, irq;
struct xenbus_transaction xbt;

ret = xenbus_alloc_evtchn(dev, &evtchn);
if (ret)
return ret;
- ret = bind_evtchn_to_irqhandler(evtchn, xenfb_event_handler,
+ irq = bind_evtchn_to_irqhandler(evtchn, xenfb_event_handler,
0, dev->devicetype, info);
- if (ret < 0) {
+ if (irq < 0) {
xenbus_free_evtchn(dev, evtchn);
xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
- return ret;
+ return irq;
}
- info->irq = ret;
-
again:
ret = xenbus_transaction_start(&xbt);
if (ret) {
xenbus_dev_fatal(dev, ret, "starting transaction");
- return ret;
+ goto unbind_irq;
}
ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
virt_to_mfn(info->page));
@@ -602,15 +600,18 @@ static int xenfb_connect_backend(struct xenbus_device *dev,
if (ret == -EAGAIN)
goto again;
xenbus_dev_fatal(dev, ret, "completing transaction");
- return ret;
+ goto unbind_irq;
}

xenbus_switch_state(dev, XenbusStateInitialised);
+ info->irq = irq;
return 0;

error_xenbus:
xenbus_transaction_end(xbt, 1);
xenbus_dev_fatal(dev, ret, "writing xenstore");
+ unbind_irq:
+ unbind_from_irqhandler(irq, info);
return ret;
}