Re: drm_mode_create_dumb_ioctl: divide error

Hi

On Sun, Aug 24, 2014 at 7:12 PM, Tommi Rantala tt.rantala@gmail.com wrote:

(gdb) info locals cpp = 0 stride = 0 size = <optimized out>

(gdb) print /x *(struct drm_mode_create_dumb *)data $13 = { height = 0xffffffff, width = 0xffffffff, bpp = 0xffffffff, flags = 0xffffffff, handle = 0xffffffff, pitch = 0xffffffff, size = 0xffffffffffffffff }

Thanks a lot for digging into this. Looks like DIV_ROUND_UP() can overflow... *check* Yes, it's defined as: #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))

Kinda unexpected that a function called "DIV" can overflow, but makes sense here. Obvious fix is to test "cpp" for zero. I will send it to dri-devel.

Thanks! David