3 Fuzz tests generate a ton of random parameter arguments to the program and then validate that none cause it to crash.
7 Typically, Travis CI will run `travis-fuzz.sh` on one of the environments the automated tests are configured for.
8 This is the most time-consuming component of the continuous integration workflow, so it is recommended that you detect
9 issues locally, and Travis merely acts as a sanity check.
11 ## How do I run fuzz tests locally?
13 You typically won't need to run the entire combination of different fuzzing tools. For local execution, `honggfuzz`
14 should be more than sufficient.
18 To install `honggfuzz`, simply run
21 cargo install honggfuzz --force
23 export HFUZZ_BUILD_ARGS="--features honggfuzz_fuzz"
29 To run the Hongg fuzzer, do
32 export CPU_COUNT=1 # replace as needed
33 export HFUZZ_RUN_ARGS="-n $CPU_COUNT --exit_upon_crash"
35 export TARGET="" # replace with the target to be fuzzed
36 cargo hfuzz run $TARGET
39 ## A fuzz test failed on Travis, what do I do?
41 You're trying to create a PR, but need to find the underlying cause of that pesky fuzz failure blocking the merge?
43 Worry not, for this is easily traced.
45 If your Travis output log looks like this:
48 Size:639 (i,b,hw,ed,ip,cmp): 0/0/0/0/0/1, Tot:0/0/0/2036/5/28604
49 Seen a crash. Terminating all fuzzing threads
51 … # a lot of lines in between
53 <0x0000000000000000> [func:UNKNOWN file: line:0 module:UNKNOWN]
54 =====================================================================
55 2d3136383734090101010101010101010101010101010101010101010101
56 010101010100040101010101010101010101010103010101010100010101
58 The command "if [ "$(rustup show | grep default | grep stable)" != "" ]; then cd fuzz && cargo test --verbose && ./travis-fuzz.sh; fi" exited with 1.
61 Simply copy the hex, and run the following from the `fuzz` directory:
64 export HEX="2d3136383734090101010101010101010101010101010101010101010101\
65 010101010100040101010101010101010101010103010101010100010101\
66 0069d07c319a4961" # adjust for your output
67 echo $HEX | xxd -r -p > ./test_cases/full_stack/your_test_case_name
69 export RUST_BACKTRACE=1
73 This will reproduce the failing fuzz input and yield a usable stack trace.