lkml.org 
[lkml]   [2017]   [Aug]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] udc: Memory leak on error path and use after free
Date
gadget_release() is responsible for cleanup dev memory.
But if net2280_probe() fails after dev allocation, then
gadget_release() become unregistered and dev memory leaks.
Also net2280_remove() calls usb_del_gadget_udc() which
perform schedule_delayed_work() with gadget_release(), so
it is possible that dev will be deallocated exactly after
this call and leads to use after free.

The patch moves deallocation from gadget_release() to
net2280_remove().

Found by Linux Driver Verififcation project (linuxtesting.org).

Signed-off-by: Anton Vasilyev <vasilyev@ispras.ru>
---
drivers/usb/gadget/udc/net2280.c | 14 +++-----------
1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/drivers/usb/gadget/udc/net2280.c b/drivers/usb/gadget/udc/net2280.c
index f608c1f..62ac876 100644
--- a/drivers/usb/gadget/udc/net2280.c
+++ b/drivers/usb/gadget/udc/net2280.c
@@ -3546,15 +3546,6 @@ static irqreturn_t net2280_irq(int irq, void *_dev)
return IRQ_HANDLED;
}

-/*-------------------------------------------------------------------------*/
-
-static void gadget_release(struct device *_dev)
-{
- struct net2280 *dev = dev_get_drvdata(_dev);
-
- kfree(dev);
-}
-
/* tear down the binding between this driver and the pci device */

static void net2280_remove(struct pci_dev *pdev)
@@ -3592,6 +3583,8 @@ static void net2280_remove(struct pci_dev *pdev)
device_remove_file(&pdev->dev, &dev_attr_registers);

ep_info(dev, "unbind\n");
+
+ kfree(dev);
}

/* wrap this driver around the specified device, but
@@ -3769,8 +3762,7 @@ static int net2280_probe(struct pci_dev *pdev, const struct pci_device_id *id)
if (retval)
goto done;

- retval = usb_add_gadget_udc_release(&pdev->dev, &dev->gadget,
- gadget_release);
+ retval = usb_add_gadget_udc(&pdev->dev, &dev->gadget);
if (retval)
goto done;
return 0;
--
2.7.4
\
 
 \ /
  Last update: 2017-08-16 15:48    [W:0.044 / U:0.708 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site