Add Fuzz-testing

[harshitasao]

Is your feature request related to a problem? Please describe.

Fuzz testing or Fuzzing is a Black Box software testing technique, which basically consists in finding implementation bugs using malformed/semi-malformed data injection in an automated fashion.

Describe the solution you'd like

Integrate the project with OSS-Fuzz by following the instructions here.

From fluentd maintainer:

Some input plugins receive data online, so it may be a good idea to add a fuzz test for them first.

• https://docs.fluentd.org/input/forward
• https://docs.fluentd.org/input/udp
• https://docs.fluentd.org/input/tcp
• https://docs.fluentd.org/input/http
• https://docs.fluentd.org/input/syslog

Describe alternatives you've considered

N/A

Additional context

Part of #4601

[harshitasao]

/assign

[kenhys]

There are some input plugins, but it is good starting point try to tackle from above plugins.
https://docs.fluentd.org/input

[kenhys]

There are some concerns integrates with OSS-Fuzz:

• No appropriate formal contact e-mail address to reach committers.
  • It was required: https://google.github.io/oss-fuzz/getting-started/accepting-new-projects/.
  • Previously, fluentd@googlegroups.com was used for such a alternative contact address, but deprecated.
• Ruby is out-of-scope in this project
  • https://google.github.io/oss-fuzz/getting-started/new-project-guide/

If I am missing the point, correc me.