This PR fixes the bug reported in #33365. The impact of the bug is not catastrophic. After a transaction is ultimately fetched, validation and propagation will be performed based on the fetched body, and any response with a mismatched type is treated as a protocol violation. An attacker could only waste the limited portion of victim’s bandwidth at most. However, the reasons for submitting this PR are as follows 1. Fetching a transaction announced with an arbitrary type is a weird behavior. 2. It aligns with efforts such as EIP-8077 and #33119 to make the fetcher smarter and reduce bandwidth waste. Regarding the `FilterType` function, it could potentially be implemented by modifying the Filter function's parameter itself, but I wasn’t sure whether changing that function is acceptable, so I left it as is. |
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| .. | ||
| bls12381 | ||
| bn256 | ||
| difficulty | ||
| rangeproof | ||
| secp256k1 | ||
| txfetcher | ||
| README.md | ||
Fuzzers
To run a fuzzer locally, you need go-fuzz installed.
First build a fuzzing-binary out of the selected package:
(cd ./rlp && CGO_ENABLED=0 go-fuzz-build .)
That command should generate a rlp-fuzz.zip in the rlp/ directory. If you are already in that directory, you can do
[user@work rlp]$ go-fuzz
2019/11/26 13:36:54 workers: 6, corpus: 3 (3s ago), crashers: 0, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 3s
2019/11/26 13:36:57 workers: 6, corpus: 3 (6s ago), crashers: 0, restarts: 1/0, execs: 0 (0/sec), cover: 1054, uptime: 6s
2019/11/26 13:37:00 workers: 6, corpus: 3 (9s ago), crashers: 0, restarts: 1/8358, execs: 25074 (2786/sec), cover: 1054, uptime: 9s
2019/11/26 13:37:03 workers: 6, corpus: 3 (12s ago), crashers: 0, restarts: 1/8497, execs: 50986 (4249/sec), cover: 1054, uptime: 12s
2019/11/26 13:37:06 workers: 6, corpus: 3 (15s ago), crashers: 0, restarts: 1/9330, execs: 74640 (4976/sec), cover: 1054, uptime: 15s
2019/11/26 13:37:09 workers: 6, corpus: 3 (18s ago), crashers: 0, restarts: 1/9948, execs: 99482 (5527/sec), cover: 1054, uptime: 18s
2019/11/26 13:37:12 workers: 6, corpus: 3 (21s ago), crashers: 0, restarts: 1/9428, execs: 122568 (5836/sec), cover: 1054, uptime: 21s
2019/11/26 13:37:15 workers: 6, corpus: 3 (24s ago), crashers: 0, restarts: 1/9676, execs: 145152 (6048/sec), cover: 1054, uptime: 24s
2019/11/26 13:37:18 workers: 6, corpus: 3 (27s ago), crashers: 0, restarts: 1/9855, execs: 167538 (6205/sec), cover: 1054, uptime: 27s
2019/11/26 13:37:21 workers: 6, corpus: 3 (30s ago), crashers: 0, restarts: 1/9645, execs: 192901 (6430/sec), cover: 1054, uptime: 30s
2019/11/26 13:37:24 workers: 6, corpus: 3 (33s ago), crashers: 0, restarts: 1/9967, execs: 219294 (6645/sec), cover: 1054, uptime: 33s
Otherwise:
go-fuzz -bin ./rlp/rlp-fuzz.zip
Notes
Once a 'crasher' is found, the fuzzer tries to avoid reporting the same vector twice, so stores the fault in the suppressions folder. Thus, if you
e.g. make changes to fix a bug, you should remove all data from the suppressions-folder, to verify that the issue is indeed resolved.
Also, if you have only one and the same exit-point for multiple different types of test, the suppression can make the fuzzer hide different types of errors. So make
sure that each type of failure is unique (for an example, see the rlp fuzzer, where a counter i is used to differentiate between failures:
if !bytes.Equal(input, output) {
panic(fmt.Sprintf("case %d: encode-decode is not equal, \ninput : %x\noutput: %x", i, input, output))
}