[PATCH AUTOSEL for 4.9 20/52] USB: gadgetfs: Fix a potential memory leak in 'dev_config()'

[alexander . levin]

From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

[ Upstream commit b6e7aeeaf235901c42ec35de4633c7c69501d303 ]

'kbuf' is allocated just a few lines above using 'memdup_user()'.
If the 'if (dev->buf)' test fails, this memory is never released.

Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
 drivers/usb/gadget/legacy/inode.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c
index f69dbd4bcd18..b8534d3f8bb0 100644
--- a/drivers/usb/gadget/legacy/inode.c
+++ b/drivers/usb/gadget/legacy/inode.c
@@ -1819,8 +1819,10 @@ dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 
 	spin_lock_irq (&dev->lock);
 	value = -EINVAL;
-	if (dev->buf)
+	if (dev->buf) {
+		kfree(kbuf);
 		goto fail;
+	}
 	dev->buf = kbuf;
 
 	/* full or low speed config */
-- 
2.11.0