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

Greg Kroah-Hartman
2020-08-17T17:17:02Z

From: Dejin Zheng <zhengdejin5@gmail.com>

[ 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@samsung.com>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200423164251.3349-1-zhengdejin5@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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