Fuzz Shrinking feature

[MeditationDuck]

Fuzz Shrinking

1. Fuzz Test

To generate a crash log when the fuzz test is failing:

wake test tests/fuzz_test.py

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2. Shrinking

To shrink the fuzz using the latest failure in the fuzz test:

wake test -SH

you can specify the test path. It verifies the testing target is the same:

wake test tests/fuzz_test.py -SH

Or specify a crash log directly:

wake test -SH .wake/logs/crashes/20241010_035704.txt

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3. Reproduce the Error by Shrunk File

To reproduce the shrunk test:

wake test -SR

You can also specify the test here as well:

wake test tests/test_fuzz.py -SR

Alternatively, specify a shrunk data file:

wake test -SR .wake/logs/shrank/20241010_042322.bin

Shrinking phase

Shrinking tries to remove flows using two algorithms.
First, remove multiple flows thus it is faster, we print the progress of the removed flow.

Second, try to remove flow one by one.

✅ remove flow by flow kind (takes O(n))

✅ remove flow by brute force (takes O(n^2)

✅ flow fail because of removed flow dependency and it is not the target fail flow, can be removed.(checked precondition and un-executed flow will be removed in brute force shrink)

• I clicked on "Allow edits from maintainers"

[jaczkal]

Does it also produce a crash log for failed invariants on assertions?

[MeditationDuck]

yes

[MeditationDuck]

Now, shrinking work with this

wake test -SH