From b3b51417d0af63fb9a06662dc292200aed9ea53f Mon Sep 17 00:00:00 2001 From: Michael Grzeschik Date: Mon, 22 May 2017 13:02:44 +0200 Subject: [PATCH] usb: usbip: set buffer pointers to NULL after free The usbip stack dynamically allocates the transfer_buffer and setup_packet of each urb that got generated by the tcp to usb stub code. As these pointers are always used only once we will set them to NULL after use. This is done likewise to the free_urb code in vudc_dev.c. This patch fixes double kfree situations where the usbip remote side added the URB_FREE_BUFFER. Cc: stable@vger.kernel.org Signed-off-by: Michael Grzeschik Acked-by: Shuah Khan Signed-off-by: Greg Kroah-Hartman --- drivers/usb/usbip/stub_main.c | 4 ++++ drivers/usb/usbip/stub_tx.c | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/drivers/usb/usbip/stub_main.c b/drivers/usb/usbip/stub_main.c index 44ab43f..af10f7b 100644 --- a/drivers/usb/usbip/stub_main.c +++ b/drivers/usb/usbip/stub_main.c @@ -262,7 +262,11 @@ void stub_device_cleanup_urbs(struct stub_device *sdev) kmem_cache_free(stub_priv_cache, priv); kfree(urb->transfer_buffer); + urb->transfer_buffer = NULL; + kfree(urb->setup_packet); + urb->setup_packet = NULL; + usb_free_urb(urb); } } diff --git a/drivers/usb/usbip/stub_tx.c b/drivers/usb/usbip/stub_tx.c index 6b1e8c3..be50cef 100644 --- a/drivers/usb/usbip/stub_tx.c +++ b/drivers/usb/usbip/stub_tx.c @@ -28,7 +28,11 @@ static void stub_free_priv_and_urb(struct stub_priv *priv) struct urb *urb = priv->urb; kfree(urb->setup_packet); + urb->setup_packet = NULL; + kfree(urb->transfer_buffer); + urb->transfer_buffer = NULL; + list_del(&priv->list); kmem_cache_free(stub_priv_cache, priv); usb_free_urb(urb); -- 2.7.4