diff options
| author | Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> | 2016-06-08 16:32:49 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-08-20 18:09:16 +0200 |
| commit | 97917f45211d7e5c0afd5f4dc33982c096a26722 (patch) | |
| tree | e2f57931a78a4c655aed6c347e5a64a1e316aa86 | |
| parent | 3ab02b35d5ce7a161ff8ad141db207837015ad6c (diff) | |
usb: renesas_usbhs: fix NULL pointer dereference in xfer_work()
commit 4fdef698383db07d829da567e0e405fc41ff3a89 upstream.
This patch fixes an issue that the xfer_work() is possible to cause
NULL pointer dereference if the usb cable is disconnected while data
transfer is running.
In such case, a gadget driver may call usb_ep_disable()) before
xfer_work() is actually called. In this case, the usbhs_pkt_pop()
will call usbhsf_fifo_unselect(), and then usbhs_pipe_to_fifo()
in xfer_work() will return NULL.
Fixes: e73a989 ("usb: renesas_usbhs: add DMAEngine support")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/renesas_usbhs/fifo.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/drivers/usb/renesas_usbhs/fifo.c b/drivers/usb/renesas_usbhs/fifo.c index f1893e08e51a..db565f620f82 100644 --- a/drivers/usb/renesas_usbhs/fifo.c +++ b/drivers/usb/renesas_usbhs/fifo.c @@ -808,20 +808,27 @@ static void xfer_work(struct work_struct *work) { struct usbhs_pkt *pkt = container_of(work, struct usbhs_pkt, work); struct usbhs_pipe *pipe = pkt->pipe; - struct usbhs_fifo *fifo = usbhs_pipe_to_fifo(pipe); + struct usbhs_fifo *fifo; struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe); struct dma_async_tx_descriptor *desc; - struct dma_chan *chan = usbhsf_dma_chan_get(fifo, pkt); + struct dma_chan *chan; struct device *dev = usbhs_priv_to_dev(priv); enum dma_transfer_direction dir; + unsigned long flags; + usbhs_lock(priv, flags); + fifo = usbhs_pipe_to_fifo(pipe); + if (!fifo) + goto xfer_work_end; + + chan = usbhsf_dma_chan_get(fifo, pkt); dir = usbhs_pipe_is_dir_in(pipe) ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV; desc = dmaengine_prep_slave_single(chan, pkt->dma + pkt->actual, pkt->trans, dir, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc) - return; + goto xfer_work_end; desc->callback = usbhsf_dma_complete; desc->callback_param = pipe; @@ -829,7 +836,7 @@ static void xfer_work(struct work_struct *work) pkt->cookie = dmaengine_submit(desc); if (pkt->cookie < 0) { dev_err(dev, "Failed to submit dma descriptor\n"); - return; + goto xfer_work_end; } dev_dbg(dev, " %s %d (%d/ %d)\n", @@ -840,6 +847,9 @@ static void xfer_work(struct work_struct *work) usbhs_pipe_set_trans_count_if_bulk(pipe, pkt->trans); dma_async_issue_pending(chan); usbhs_pipe_enable(pipe); + +xfer_work_end: + usbhs_unlock(priv, flags); } /* |