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

[<gregkh@linuxfoundation.org>]

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

    tty: mxs-auart: 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 6734330654dac550f12e932996b868c6d0dcb421 Mon Sep 17 00:00:00 2001
From: Kangjie Lu <kjlu@umn.edu>
Date: Thu, 14 Mar 2019 02:21:51 -0500
Subject: tty: mxs-auart: fix a potential NULL pointer dereference

In case ioremap fails, the fix returns -ENOMEM to avoid NULL
pointer dereferences.
Multiple places use port.membase.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/tty/serial/mxs-auart.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index 27235a526cce..4c188f4079b3 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -1686,6 +1686,10 @@ static int mxs_auart_probe(struct platform_device *pdev)
 
 	s->port.mapbase = r->start;
 	s->port.membase = ioremap(r->start, resource_size(r));
+	if (!s->port.membase) {
+		ret = -ENOMEM;
+		goto out_disable_clks;
+	}
 	s->port.ops = &mxs_auart_ops;
 	s->port.iotype = UPIO_MEM;
 	s->port.fifosize = MXS_AUART_FIFO_SIZE;
-- 
2.21.0