A memory leak can occur in dtls1_buffer_record if either of the calls to
ssl3_setup_buffers or pqueue_insert fail. The former will fail if there
is a malloc failure, whilst the latter will fail if attempting to add a
duplicate record to the queue. This should never happen because
duplicate records should be detected and dropped before any attempt to
add them to the queue. Unfortunately records that arrive that are for
the next epoch are not being recorded correctly, and therefore replays
are not being detected. Additionally, these "should not happen" failures
that can occur in dtls1_buffer_record are not being treated as fatal and
therefore an attacker could exploit this by sending repeated replay
records for the next epoch, eventually causing a DoS through memory
exhaustion.
Thanks to Chris Mueller for reporting this issue and providing initial
analysis and a patch. Further analysis and the final patch was performed
by Matt Caswell from the OpenSSL development team.
CVE-2015-0206
(Imported from upstream's 7c6a3cf2375f5881ef3f3a58ac0fbd0b4663abd1).
Change-Id: I765fe61c75bc295bcc4ab356b8a5ce88c8964764
Reviewed-on: https://boringssl-review.googlesource.com/2782
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
44e2709cd6