On 9/18/23 22:52, Sergey Shtylyov wrote:
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@omp.ru Cc: stable@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;
As mentioned in the other mail, both patches are not needed.
Helge
if (p->state != FBINFO_STATE_RUNNING) return;