Uri Lublin authored Jan 09, 2020 and Frediano Ziglio committed Jan 13, 2020

Return early if the cursor received from X is too big.

This fixes a covscan error: "sign_extension: Suspicious implicit sign extension":
  "cursor->width" with type "unsigned short" (16 bits, unsigned) is promoted in
  "cursor->width * cursor->height" to type "int" (32 bits, signed), then sign-extended
  to type "unsigned long" (64 bits, unsigned). If "cursor->width * cursor->height" is
  greater than 0x7FFFFFFF, the upper bits of the result will all be 1.

Signed-off-by: Uri Lublin <uril@redhat.com>
Acked-by: Frediano Ziglio <fziglio@redhat.com>