Alex Loiko 38c15d3995 Template argument and corpora for Audio Processing Fuzzer.
We found out that

  int16_t x = test::FuzzDataHelper::ReadOrDefaultValue(0)

reads 4 bytes from the fuzzer input instead of 2. That means that
almost half the bits in the input data to audio_processing_fuzzer are
ignored. This change adds template arguments to force reading 2 bytes
when we only need 2.

We also add a small manually generated corpus. During local testing we
let the fuzzer run for a few hours on an empty corpus. Adding the
manually-generated files resulted in an immediate coverage increase by
~3%, and then by another 3% over the next few hours.

The manually generated corpus contains a short segment of speech with
real echo. We suspect that triggering Voice Activity Detection or echo
estimation filter convergence can be difficult for an automatic
fuzzer.

We remove the Level Controller config. We read 20 bytes extra after the
config to guard against future configuration changes.

Bug: webrtc:7820
Change-Id: If60c04f53b27c519c349a40bd13664eef7999368
Reviewed-on: https://webrtc-review.googlesource.com/58744
Reviewed-by: Sam Zackrisson <saza@webrtc.org>
Commit-Queue: Alex Loiko <aleloi@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22269}
2018-03-02 14:00:39 +00:00
..

This is a collection of corpora for various WebRTC fuzzers. To use
them, the gn targets define seed_corpus=$corpus_dir, which causes the
ClusterFuzz upload bot to bundle $corpus_dir and upload it.

The format is simple: one file per test case. Specific notes are
included below.

### SDP ###
This corpus was initially assembled manually from the following
sources:

  - curl --silent https://www.ietf.org/rfc/rfc4317.txt | grep '^[ a-z]*=[^=]*$' | sed 's/^[[:space:]]*//' | awk -v RS='(^|\n)v=' '/./ {print "v="$0 > NR".sdp"}'
  - all the SDPs used in the parser unit tests
  - some manually gathered SDPs from Firefox and Opera

The SDP tokens come from:

 -  grep "^static const " webrtc/api/webrtcsdp.cc | cut -d'=' -f2 | cut -d ';' -f1 | tr -d '"' | tr -d "'" | tr -d ' ' | sort -u | grep -v '^(\n|\r|\r\n)$|^$' | sed -e 's/^/"/' -e 's/$/"/' | tail -n +2

### STUN ###
This corpus was initially assembled from the STUN unit tests, together
with a crash that it found relatively quickly.

### RT(C)P ###
This corpus was initially assembled from the unittests. RTCP was
minimised first.

There is also rt(c?)p-corpus-with-extra-byte, in which each sample is
prefixed by the byte 0xff. Some of the rtp fuzzers need to decide
which header extensions to enable, and the first byte of the fuzz data
is used for this.

### PseudoTCP ###
Very small corpus minimised from the unit tests.