[PATCH 2/2] video: fbdev: core: syscopyarea: fix sloppy typing

[Sergey Shtylyov]

In sys_copyarea(), when initializing *unsigned long const* bits_per_line
__u32 typed fb_fix_screeninfo::line_length gets multiplied by 8u -- which
might overflow __u32; multiplying by 8UL instead should fix that...
Also, that bits_per_line constant is used to advance *unsigned* src_idx
and dst_idx variables -- which might be overflowed as well; declaring
them as *unsigned long* should fix that too...

Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.

Signed-off-by: Sergey Shtylyov <s.shtylyov at omp.ru>
Cc: stable at vger.kernel.org
---
 drivers/video/fbdev/core/syscopyarea.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/core/syscopyarea.c b/drivers/video/fbdev/core/syscopyarea.c
index c1eda3190968..1035131383a6 100644
--- a/drivers/video/fbdev/core/syscopyarea.c
+++ b/drivers/video/fbdev/core/syscopyarea.c
@@ -316,10 +316,11 @@ void sys_copyarea(struct fb_info *p, const struct fb_copyarea *area)
 {
 	u32 dx = area->dx, dy = area->dy, sx = area->sx, sy = area->sy;
 	u32 height = area->height, width = area->width;
-	unsigned long const bits_per_line = p->fix.line_length*8u;
+	unsigned long const bits_per_line = p->fix.line_length * 8UL;
 	unsigned long *base = NULL;
 	int bits = BITS_PER_LONG, bytes = bits >> 3;
-	unsigned dst_idx = 0, src_idx = 0, rev_copy = 0;
+	unsigned long dst_idx = 0, src_idx = 0;
+	unsigned int rev_copy = 0;
 
 	if (p->state != FBINFO_STATE_RUNNING)
 		return;
-- 
2.26.3