| From 0e865f0c31928d6a313269ef624907eec55287c4 Mon Sep 17 00:00:00 2001 |
| From: Pavel Skripkin <paskripkin@gmail.com> |
| Date: Tue, 27 Jul 2021 19:59:57 +0300 |
| Subject: can: usb_8dev: fix memory leak |
| |
| From: Pavel Skripkin <paskripkin@gmail.com> |
| |
| commit 0e865f0c31928d6a313269ef624907eec55287c4 upstream. |
| |
| In usb_8dev_start() 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 usb_8dev_start) 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: 0024d8ad1639 ("can: usb_8dev: Add support for USB2CAN interface from 8 devices") |
| Link: https://lore.kernel.org/r/d39b458cd425a1cf7f512f340224e6e9563b07bd.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> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/net/can/usb/usb_8dev.c | 15 +++++++++++++-- |
| 1 file changed, 13 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/net/can/usb/usb_8dev.c |
| +++ b/drivers/net/can/usb/usb_8dev.c |
| @@ -137,7 +137,8 @@ struct usb_8dev_priv { |
| u8 *cmd_msg_buffer; |
| |
| struct mutex usb_8dev_cmd_lock; |
| - |
| + void *rxbuf[MAX_RX_URBS]; |
| + dma_addr_t rxbuf_dma[MAX_RX_URBS]; |
| }; |
| |
| /* tx frame */ |
| @@ -733,6 +734,7 @@ static int usb_8dev_start(struct usb_8de |
| for (i = 0; i < MAX_RX_URBS; i++) { |
| struct urb *urb = NULL; |
| u8 *buf; |
| + dma_addr_t buf_dma; |
| |
| /* create a URB, and a buffer for it */ |
| urb = usb_alloc_urb(0, GFP_KERNEL); |
| @@ -742,7 +744,7 @@ static int usb_8dev_start(struct usb_8de |
| } |
| |
| buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL, |
| - &urb->transfer_dma); |
| + &buf_dma); |
| if (!buf) { |
| netdev_err(netdev, "No memory left for USB buffer\n"); |
| usb_free_urb(urb); |
| @@ -750,6 +752,8 @@ static int usb_8dev_start(struct usb_8de |
| break; |
| } |
| |
| + urb->transfer_dma = buf_dma; |
| + |
| usb_fill_bulk_urb(urb, priv->udev, |
| usb_rcvbulkpipe(priv->udev, |
| USB_8DEV_ENDP_DATA_RX), |
| @@ -767,6 +771,9 @@ static int usb_8dev_start(struct usb_8de |
| break; |
| } |
| |
| + priv->rxbuf[i] = buf; |
| + priv->rxbuf_dma[i] = buf_dma; |
| + |
| /* Drop reference, USB core will take care of freeing it */ |
| usb_free_urb(urb); |
| } |
| @@ -836,6 +843,10 @@ static void unlink_all_urbs(struct usb_8 |
| |
| usb_kill_anchored_urbs(&priv->rx_submitted); |
| |
| + for (i = 0; i < MAX_RX_URBS; ++i) |
| + usb_free_coherent(priv->udev, RX_BUFFER_SIZE, |
| + priv->rxbuf[i], priv->rxbuf_dma[i]); |
| + |
| usb_kill_anchored_urbs(&priv->tx_submitted); |
| atomic_set(&priv->active_tx_urbs, 0); |
| |