When I run

./openssl s_server -dtls1 -no_ecdhe -timeout -cert large.pem

against

./openssl s_client -dtls1

I'll get a Segmentation fault on the client side. I attached the
certificate (including the private key) to this bug report. GDB told me
that the error happened at d1_both.c:539:

return frag->msg_header.frag_len;

The pointer frag was freed 6 lines above. So I guess the problem is that
this function accesses a data structure that has already been freed. To
fix this bug I created a temporary variable and copied the value of
frag->msg_header.frag_len into that variable right before the call to
free(). The return statement then uses this copy instead of accessing
already freed memory.
With this change applied s_client does not crash any more. I attached
the patch to this bug report.

-Daniel
Download large.pem
text/plain 3.6k
-----BEGIN CERTIFICATE-----
MIIFwzCCBKugAwIBAgIJAIsAUklUWDcIMA0GCSqGSIb3DQEBBQUAMIHwMQ0wCwYD
VQQDEwRUZXN0MQ0wCwYDVQQDEwRUZXN0MQ0wCwYDVQQDEwRUZXN0MQ0wCwYDVQQD
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-----END CERTIFICATE-----
-----BEGIN RSA PRIVATE KEY-----
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-----END RSA PRIVATE KEY-----