GnuTLS accepts a certificate which has a fractional validity

Description of problem:

As for a certificate, its validity should not be fractional according to RFCs 5280 and 6818. However, GnuTLS accepts such a certificate.

Version of gnutls used:

v3.3.25, v3.4.16, and v3.5.5

Distributor of gnutls (e.g., Ubuntu, Fedora, RHEL)

Ubuntu 1604 x64

How reproducible:

Steps to Reproduce:

certtool --verify --load-ca-certificate=ca.pem < 22.pem

Actual results:

The certificate is trusted.

Expected results:

Reject this invalid certificate.

test_cases.zip