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

[ 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>

diff --git a/drivers/video/fbdev/sm501fb.c b/drivers/video/fbdev/sm501fb.c
index d0a4e2f..d215faa 100644 (file)
--- a/drivers/video/fbdev/sm501fb.c
+++ b/drivers/video/fbdev/sm501fb.c
@@ -1600,6 +1600,7 @@ static int sm501fb_start(struct sm501fb_info *info,
        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;
        }