can: esd_usb2: fix memory leak

In esd_usb2_setup_rx_urbs() MAX_RX_URBS coherent buffers are allocated
and there is nothing, that frees them:

1) In callback function the urb is resubmitted and that's all
2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER
   is not set (see esd_usb2_setup_rx_urbs) and this flag cannot be used
   with coherent buffers.

So, all allocated buffers should be freed with usb_free_coherent()
explicitly.

Side note: This code looks like a copy-paste of other can drivers. The
same patch was applied to mcba_usb driver and it works nice with real
hardware. There is no change in functionality, only clean-up code for
coherent buffers.

Fixes: 96d8e90382 ("can: Add driver for esd CAN-USB/2 device")
Link: https://lore.kernel.org/r/b31b096926dcb35998ad0271aac4b51770ca7cc8.1627404470.git.paskripkin@gmail.com
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Pavel Skripkin 2021-07-27 20:00:46 +03:00 committed by Marc Kleine-Budde
parent 9969e3c5f4
commit 928150fad4
1 changed files with 15 additions and 1 deletions

View File

@ -195,6 +195,8 @@ struct esd_usb2 {
int net_count;
u32 version;
int rxinitdone;
void *rxbuf[MAX_RX_URBS];
dma_addr_t rxbuf_dma[MAX_RX_URBS];
};
struct esd_usb2_net_priv {
@ -545,6 +547,7 @@ static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
for (i = 0; i < MAX_RX_URBS; i++) {
struct urb *urb = NULL;
u8 *buf = NULL;
dma_addr_t buf_dma;
/* create a URB, and a buffer for it */
urb = usb_alloc_urb(0, GFP_KERNEL);
@ -554,7 +557,7 @@ static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
}
buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
&urb->transfer_dma);
&buf_dma);
if (!buf) {
dev_warn(dev->udev->dev.parent,
"No memory left for USB buffer\n");
@ -562,6 +565,8 @@ static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
goto freeurb;
}
urb->transfer_dma = buf_dma;
usb_fill_bulk_urb(urb, dev->udev,
usb_rcvbulkpipe(dev->udev, 1),
buf, RX_BUFFER_SIZE,
@ -574,8 +579,12 @@ static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
usb_unanchor_urb(urb);
usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
urb->transfer_dma);
goto freeurb;
}
dev->rxbuf[i] = buf;
dev->rxbuf_dma[i] = buf_dma;
freeurb:
/* Drop reference, USB core will take care of freeing it */
usb_free_urb(urb);
@ -663,6 +672,11 @@ static void unlink_all_urbs(struct esd_usb2 *dev)
int i, j;
usb_kill_anchored_urbs(&dev->rx_submitted);
for (i = 0; i < MAX_RX_URBS; ++i)
usb_free_coherent(dev->udev, RX_BUFFER_SIZE,
dev->rxbuf[i], dev->rxbuf_dma[i]);
for (i = 0; i < dev->net_count; i++) {
priv = dev->nets[i];
if (priv) {