[PATCH 4.19 057/168] console: newport_con: fix an issue about leak related system resources

[Greg Kroah-Hartman]

From: Dejin Zheng <zhengdejin5@xxxxxxxxx>

[ Upstream commit fd4b8243877250c05bb24af7fea5567110c9720b ]

A call of the function do_take_over_console() can fail here.
The corresponding system resources were not released then.
Thus add a call of iounmap() and release_mem_region()
together with the check of a failure predicate. and also
add release_mem_region() on device removal.

Fixes: e86bb8acc0fdc ("[PATCH] VT binding: Make newport_con support binding")
Suggested-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Signed-off-by: Dejin Zheng <zhengdejin5@xxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxx>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20200423164251.3349-1-zhengdejin5@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/video/console/newport_con.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/video/console/newport_con.c b/drivers/video/console/newport_con.c
index 7f2526b43b336..cc2fb50431840 100644
--- a/drivers/video/console/newport_con.c
+++ b/drivers/video/console/newport_con.c
@@ -31,6 +31,8 @@
 #include <linux/linux_logo.h>
 #include <linux/font.h>
 
+#define NEWPORT_LEN	0x10000
+
 #define FONT_DATA ((unsigned char *)font_vga_8x16.data)
 
 /* borrowed from fbcon.c */
@@ -42,6 +44,7 @@
 static unsigned char *font_data[MAX_NR_CONSOLES];
 
 static struct newport_regs *npregs;
+static unsigned long newport_addr;
 
 static int logo_active;
 static int topscan;
@@ -701,7 +704,6 @@ const struct consw newport_con = {
 static int newport_probe(struct gio_device *dev,
 			 const struct gio_device_id *id)
 {
-	unsigned long newport_addr;
 	int err;
 
 	if (!dev->resource.start)
@@ -711,7 +713,7 @@ static int newport_probe(struct gio_device *dev,
 		return -EBUSY; /* we only support one Newport as console */
 
 	newport_addr = dev->resource.start + 0xF0000;
-	if (!request_mem_region(newport_addr, 0x10000, "Newport"))
+	if (!request_mem_region(newport_addr, NEWPORT_LEN, "Newport"))
 		return -ENODEV;
 
 	npregs = (struct newport_regs *)/* ioremap cannot fail */
@@ -719,6 +721,11 @@ static int newport_probe(struct gio_device *dev,
 	console_lock();
 	err = do_take_over_console(&newport_con, 0, MAX_NR_CONSOLES - 1, 1);
 	console_unlock();
+
+	if (err) {
+		iounmap((void *)npregs);
+		release_mem_region(newport_addr, NEWPORT_LEN);
+	}
 	return err;
 }
 
@@ -726,6 +733,7 @@ static void newport_remove(struct gio_device *dev)
 {
 	give_up_console(&newport_con);
 	iounmap((void *)npregs);
+	release_mem_region(newport_addr, NEWPORT_LEN);
 }
 
 static struct gio_device_id newport_ids[] = {
-- 
2.25.1