In cfb_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@omp.ru Cc: stable@vger.kernel.org --- drivers/video/fbdev/core/cfbcopyarea.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/video/fbdev/core/cfbcopyarea.c b/drivers/video/fbdev/core/cfbcopyarea.c index 6d4bfeecee35..b67ba69ea2fb 100644 --- a/drivers/video/fbdev/core/cfbcopyarea.c +++ b/drivers/video/fbdev/core/cfbcopyarea.c @@ -382,10 +382,11 @@ void cfb_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 __iomem *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; u32 bswapmask = fb_compute_bswapmask(p);
if (p->state != FBINFO_STATE_RUNNING)