commit 1843abd03250115af6cec0892683e70cf2297c25 upstream.
Userspace could have munmapped the area before doing unmapping from
the gmap. This would leave us with a valid vmaddr, but an invalid vma
from which we would try to zap memory.
Let's check before using the vma.
Fixes: 1e133ab296f3 ("s390/mm: split arch/s390/mm/pgtable.c")
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Message-Id: <20180816082432.78828-1-frankja@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
3921d5b8a1