[llvm_libc] Add project files for llvm-libc fuzzing. #3418
Closed
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Travis tests have failedHey @PaulkaToast, 2nd Build./infra/travis/travis_build.py3rd Build./infra/travis/travis_build.pyTravisBuddy Request Identifier: a6e98270-56b2-11ea-8ad8-19cca21d7143 |
jonathanmetzman
approved these changes
Feb 24, 2020
There was a problem hiding this comment.
I think we approve this project since it's LLVM. But you need to fix the build errors before landing.
When you run the fuzzer what's the number you see next to inline 8-bit counters? Our tests block fuzzers with less than 100 because 1. often this is due to user error when building 2. If not user error, the target is so small that continuous fuzzing isn't so useful.
For the AFL failure, I assume you won't be able to easily get AFL working since AFL needs -fsanitize-trace-pc-guard. I don't know how exactly LLVM's cmake does coverage instrumentation, but it doesn't seem to support this. All other LLVM projects disable LLVM.
Travis tests have failedHey @PaulkaToast, 1st Build./infra/travis/travis_build.py2nd Build./infra/travis/travis_build.pyTravisBuddy Request Identifier: fde515e0-56c0-11ea-8ad8-19cca21d7143 |
The fuzzer code is really short right now because we are calling into the system memcpy and strlen, this first fuzzer is meant to be a proof of concept to see if the build system and oss-fuzz integration works. It will get more fleshed out later and have more edges to instrument. |
We might have a way of whitelisting this project (@Dor1s WDYT?) but it would be easier for us to not to do this. |
|
I'm not supportive of whitelisting tiny fuzz targets. Please see #2469 (comment) for the reasoning :) |
Yes as Max said, we would prefer to have a proper fuzz target as otherwise it would fail our instrumentation checks (for minimum number of program edges). |
Travis tests have failedHey @PaulkaToast, 3rd Build./infra/travis/travis_build.pyTravisBuddy Request Identifier: 1bb17450-8151-11ea-b3db-bd01bce4ecd4 |
Travis tests have failedHey @PaulkaToast, 2nd Build./infra/travis/travis_build.py3rd Build./infra/travis/travis_build.pyTravisBuddy Request Identifier: 4e80f960-8155-11ea-b3db-bd01bce4ecd4 |
Travis tests have failedHey @PaulkaToast, 1st Build./infra/travis/travis_build.py2nd Build./infra/travis/travis_build.pyTravisBuddy Request Identifier: 7ca65420-8155-11ea-b3db-bd01bce4ecd4 |
|
Hey @PaulkaToast Are you still interested in landing this PR? |
|
Sorry for the long silence here. I plan to submit a larger fuzz target later this week. I am not sure at this point if it better to do it with a different pull request or just add to it (if at all possible). |
Thanks! It doesn't really matter to me if you want to add a big fuzzer in this PR or in another. You can do whatever is convenient/works for you. |
|
I have added few more complex fuzz targets in LLVM libc. However, the maximum I see for the 8-bit counters is 22. IIUC, this still does not meet the bar, correct? |
Don't think so. I think we probably need at least 100. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Added project files for llvm_libc to integrate with oss-fuzz.
@sivachandra