patch "tty: atmel_serial: fix a potential NULL pointer dereference" added to tty-linus

This is a note to let you know that I've just added the patch titled

tty: atmel_serial: fix a potential NULL pointer dereference

to my tty git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git
in the tty-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From c85be041065c0be8bc48eda4c45e0319caf1d0e5 Mon Sep 17 00:00:00 2001
From: Kangjie Lu <[email protected]>
Date: Fri, 15 Mar 2019 12:16:06 -0500
Subject: tty: atmel_serial: fix a potential NULL pointer dereference

In case dmaengine_prep_dma_cyclic fails, the fix returns a proper error code to avoid NULL pointer dereference.

---
 drivers/tty/serial/atmel_serial.c | 4 ++++
 1 file changed, 4 insertions(+)

index 05147fe24343..41b728d223d1 100644
@@ -1288,6 +1288,10 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
 					 sg_dma_len(&atmel_port->sg_rx)/2,
 					 DMA_DEV_TO_MEM,
 					 DMA_PREP_INTERRUPT);
+	if (!desc) {
+		dev_err(port->dev, "Preparing DMA cyclic failed\n");
+		goto chan_err;
+	}
 	desc->callback = atmel_complete_rx_dma;
 	desc->callback_param = port;
 	atmel_port->desc_rx = desc;

2.21.0