While it's always safe to read |SSL_MAX_SSL_SESSION_ID_LENGTH| bytes
from an |SSL_SESSION|'s |session_id| array, the hash function would do
so with without considering if all those bytes had been written to.
This change checks |session_id_length| before possibly reading
uninitialised memory. Since the result of the hash function was already
attacker controlled, and since a lookup of a short session ID will
always fail, it doesn't appear that this is anything more than a clean
up.
BUG=586800
Change-Id: I5f59f245b51477d6d4fa2cdc20d40bb6b4a3eae7
Reviewed-on: https://boringssl-review.googlesource.com/7150
Reviewed-by: David Benjamin <davidben@google.com>
Adam Langley
e976e4349d