diff options
| author | Rhett Aultman <rhett.aultman@samsara.com> | 2022-07-03 19:33:06 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-07-12 16:34:49 +0200 |
| commit | 0e60230bc64355c80abe993d1719fdb318094e20 (patch) | |
| tree | 611bff9100d2bd484b4ebd5028abd15a0ea58157 /drivers/net/can | |
| parent | 8cfa1a33b0fba49515cf1db6b039e0cf3cbce638 (diff) | |
can: gs_usb: gs_usb_open/close(): fix memory leak
commit 2bda24ef95c0311ab93bda00db40486acf30bd0a upstream.
The gs_usb driver appears to suffer from a malady common to many USB
CAN adapter drivers in that it performs usb_alloc_coherent() to
allocate a number of USB request blocks (URBs) for RX, and then later
relies on usb_kill_anchored_urbs() to free them, but this doesn't
actually free them. As a result, this may be leaking DMA memory that's
been used by the driver.
This commit is an adaptation of the techniques found in the esd_usb2
driver where a similar design pattern led to a memory leak. It
explicitly frees the RX URBs and their DMA memory via a call to
usb_free_coherent(). Since the RX URBs were allocated in the
gs_can_open(), we remove them in gs_can_close() rather than in the
disconnect function as was done in esd_usb2.
For more information, see the 928150fad41b ("can: esd_usb2: fix memory
leak").
Link: https://lore.kernel.org/all/alpine.DEB.2.22.394.2206031547001.1630869@thelappy
Fixes: d08e973a77d1 ("can: gs_usb: Added support for the GS_USB CAN devices")
Cc: stable@vger.kernel.org
Signed-off-by: Rhett Aultman <rhett.aultman@samsara.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/can')
| -rw-r--r-- | drivers/net/can/usb/gs_usb.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c index d68d698f2606..e26b3d6f5b48 100644 --- a/drivers/net/can/usb/gs_usb.c +++ b/drivers/net/can/usb/gs_usb.c @@ -185,6 +185,8 @@ struct gs_can { struct usb_anchor tx_submitted; atomic_t active_tx_urbs; + void *rxbuf[GS_MAX_RX_URBS]; + dma_addr_t rxbuf_dma[GS_MAX_RX_URBS]; }; /* usb interface struct */ @@ -594,6 +596,7 @@ static int gs_can_open(struct net_device *netdev) for (i = 0; i < GS_MAX_RX_URBS; i++) { struct urb *urb; u8 *buf; + dma_addr_t buf_dma; /* alloc rx urb */ urb = usb_alloc_urb(0, GFP_KERNEL); @@ -604,7 +607,7 @@ static int gs_can_open(struct net_device *netdev) buf = usb_alloc_coherent(dev->udev, sizeof(struct gs_host_frame), GFP_KERNEL, - &urb->transfer_dma); + &buf_dma); if (!buf) { netdev_err(netdev, "No memory left for USB buffer\n"); @@ -612,6 +615,8 @@ static int gs_can_open(struct net_device *netdev) return -ENOMEM; } + urb->transfer_dma = buf_dma; + /* fill, anchor, and submit rx urb */ usb_fill_bulk_urb(urb, dev->udev, @@ -635,10 +640,17 @@ static int gs_can_open(struct net_device *netdev) rc); usb_unanchor_urb(urb); + usb_free_coherent(dev->udev, + sizeof(struct gs_host_frame), + buf, + buf_dma); usb_free_urb(urb); break; } + dev->rxbuf[i] = buf; + dev->rxbuf_dma[i] = buf_dma; + /* Drop reference, * USB core will take care of freeing it */ @@ -703,13 +715,20 @@ static int gs_can_close(struct net_device *netdev) int rc; struct gs_can *dev = netdev_priv(netdev); struct gs_usb *parent = dev->parent; + unsigned int i; netif_stop_queue(netdev); /* Stop polling */ parent->active_channels--; - if (!parent->active_channels) + if (!parent->active_channels) { usb_kill_anchored_urbs(&parent->rx_submitted); + for (i = 0; i < GS_MAX_RX_URBS; i++) + usb_free_coherent(dev->udev, + sizeof(struct gs_host_frame), + dev->rxbuf[i], + dev->rxbuf_dma[i]); + } /* Stop sending URBs */ usb_kill_anchored_urbs(&dev->tx_submitted); |