Patch "sm501fb: don't return zero on failure path in sm501fb_start()" has been added to the 4.4-stable tree

Patch "sm501fb: don't return zero on failure path in sm501fb_start()" has been added to the 4.4-stable tree

[gregkh]

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

    sm501fb: don't return zero on failure path in sm501fb_start()

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     sm501fb-don-t-return-zero-on-failure-path-in-sm501fb_start.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Mar 22 14:57:32 CET 2018
From: Alexey Khoroshilov <khoroshilov@ispras.ru>
Date: Tue, 2 May 2017 13:47:53 +0200
Subject: sm501fb: don't return zero on failure path in sm501fb_start()

From: Alexey Khoroshilov <khoroshilov@ispras.ru>


[ Upstream commit dc85e9a87420613b3129d5cc5ecd79c58351c546 ]

If fbmem iomemory mapping failed, sm501fb_start() breaks off
initialization, deallocates resources, but returns zero.
As a result, double deallocation can happen in sm501fb_stop().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/video/fbdev/sm501fb.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/video/fbdev/sm501fb.c
+++ b/drivers/video/fbdev/sm501fb.c
@@ -1600,6 +1600,7 @@ static int sm501fb_start(struct sm501fb_
 	info->fbmem = ioremap(res->start, resource_size(res));
 	if (info->fbmem == NULL) {
 		dev_err(dev, "cannot remap framebuffer\n");
+		ret = -ENXIO;
 		goto err_mem_res;
 	}
 


Patches currently in stable-queue which might be from khoroshilov@ispras.ru are

queue-4.4/sm501fb-don-t-return-zero-on-failure-path-in-sm501fb_start.patch