usb: renesas_usbhs: fix NULL pointer dereference in dma_release_channel()
This patch fixes an issue that the following commit causes NULL
pointer dereference in dma_release_channel().
"usb: renesas_usbhs: add support for requesting DT DMA"
(commit id abd2dbf6bb1b5f3a03a8c76b1a8879da1dd30caa)
The usbhsf_dma_init_dt() should set fifo->{t,r}x_chan to NULL if
dma_request_slave_channel_reason() returns IS_ERR value.
Otherwise, usbhsf_dma_quit() will call dma_release_channel(), and then
NULL pointer dereference happens.
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Simon Horman <horms+renesas@verge.net.au>
Reported-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/renesas_usbhs/fifo.c b/drivers/usb/renesas_usbhs/fifo.c
index 4c086b1..d891bff 100644
--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -1072,7 +1072,11 @@
static void usbhsf_dma_init_dt(struct device *dev, struct usbhs_fifo *fifo)
{
fifo->tx_chan = dma_request_slave_channel_reason(dev, "tx");
+ if (IS_ERR(fifo->tx_chan))
+ fifo->tx_chan = NULL;
fifo->rx_chan = dma_request_slave_channel_reason(dev, "rx");
+ if (IS_ERR(fifo->rx_chan))
+ fifo->rx_chan = NULL;
}
static void usbhsf_dma_init(struct usbhs_priv *priv,