[PATCH v2] usb: gadget: gadgetfs: correct dev state

From: Marcus Nutzinger
Date: Thu Jun 05 2014 - 11:17:26 EST


This reverts commit 1826e9b1 (usb: gadget: gadgetfs: use
after free in dev_release()) and places the call to
put_dev() after setting the state.

If this is not the final call to dev_release() and the
state is not reset to STATE_DEV_DISABLED and hence all
further open() calls to the gadgetfs ep0 device will
fail with EBUSY.

Signed-off-by: Marcus Nutzinger <marcus.nutzinger@xxxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Christoph Muellner <christoph.muellner@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/usb/gadget/inode.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c
index a925d0c..6330528 100644
--- a/drivers/usb/gadget/inode.c
+++ b/drivers/usb/gadget/inode.c
@@ -1264,8 +1264,13 @@ dev_release (struct inode *inode, struct file *fd)

kfree (dev->buf);
dev->buf = NULL;
- put_dev (dev);

+ /* other endpoints were all decoupled from this device */
+ spin_lock_irq(&dev->lock);
+ dev->state = STATE_DEV_DISABLED;
+ spin_unlock_irq(&dev->lock);
+
+ put_dev (dev);
return 0;
}

--
1.9.0

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