kselftest: vm: check errnos in mdwe_test

Invalid prctls return a negative code and set errno.  It's good practice
to check that errno is set as expected.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Florent Revest <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Acked-by: Catalin Marinas <[email protected]>
Cc: Alexey Izbyshev <[email protected]>
Cc: Anshuman Khandual <[email protected]>
Cc: Ayush Jain <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Greg Thelen <[email protected]>
Cc: Joey Gouly <[email protected]>
Cc: KP Singh <[email protected]>
Cc: Mark Brown <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Szabolcs Nagy <[email protected]>
Cc: Topi Miettinen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions