ukvm: Check limits in pread_in_full()
ukvm: Check limits in pread_in_full()

Check that total amount to be read is <= SSIZE_MAX.

djwillia/solo5,mato/solo5,mato/solo5,Weichen81/solo5,Solo5/solo5,djwillia/solo5,Weichen81/solo5,Solo5/solo5,djwillia/solo5,mato/solo5,Weichen81/solo5