Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Golang coverage summary for each fuzz target #4671

Merged
merged 3 commits into from
Nov 20, 2020
Merged

Golang coverage summary for each fuzz target #4671

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
bfbb56b
Golang coverage summary for each fuzz target
catenacyber Nov 20, 2020
4e87c6c
Document usage of compile_go_fuzzer
catenacyber Nov 20, 2020
cb373b9
update the documentation change
Dor1s Nov 20, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
25 changes: 11 additions & 14 deletions docs/getting-started/new-project-guide/go_lang.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -74,21 +74,18 @@ RUN go get github.com/ianlancetaylor/demangle
In order to build a Go fuzz target, you need to call `go-fuzz`
command first, and then link the resulting `.a` file against
`$LIB_FUZZING_ENGINE` using the `$CXX $CXXFLAGS ...` command.
[Example](https://github.com/google/oss-fuzz/blob/356f2b947670b7eb33a1f535c71bc5c87a60b0d1/projects/syzkaller/build.sh#L19):

```sh
function compile_fuzzer {
path=$1
function=$2
fuzzer=$3
# Compile and instrument all Go files relevant to this fuzz target.
go-fuzz -func $function -o $fuzzer.a $path
The best way to do this is by using a `compile_go_fuzzer` script,
as it also supports coverage builds.

# Link Go code ($fuzzer.a) with fuzzing engine to produce fuzz target binary.
$CXX $CXXFLAGS $LIB_FUZZING_ENGINE $fuzzer.a -o $OUT/$fuzzer
}
A usage example from go-dns project is

compile_fuzzer ./pkg/compiler Fuzz compiler_fuzzer
compile_fuzzer ./prog/test FuzzDeserialize prog_deserialize_fuzzer
```sh
compile_go_fuzzer github.com/miekg/dns FuzzNewRR fuzz_newrr fuzz
```

Arguments are :
* path of the package with the fuzz target
* name of the fuzz function
* name of the fuzzer to be built
* optional tag to be used by `go build` and such
19 changes: 13 additions & 6 deletions infra/base-images/base-runner/coverage
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -111,6 +111,18 @@ function run_fuzz_target {
fi
}

function run_go_fuzz_target {
local target=$1

cd $GOPATH/src
echo "Running go target $target"
export FUZZ_CORPUS_DIR="/corpus/${target}/"
export FUZZ_PROFILE_NAME="$DUMPS_DIR/$target.perf"
bash $OUT/$target $DUMPS_DIR/$target.profdata
$SYSGOPATH/bin/gocovsum $DUMPS_DIR/$target.profdata > $FUZZER_STATS_DIR/$target.json
cd $OUT
}

export SYSGOPATH=$GOPATH
export GOPATH=$OUT/$GOPATH
# Run each fuzz target, generate raw coverage dumps.
Expand All @@ -121,12 +133,7 @@ for fuzz_target in $FUZZ_TARGETS; do
if [[ $FUZZING_ENGINE != "none" ]]; then
grep "go test -run" $fuzz_target > /dev/null 2>&1 || continue
fi
cd $GOPATH/src
echo "Running go target $fuzz_target"
export FUZZ_CORPUS_DIR="/corpus/${fuzz_target}/"
export FUZZ_PROFILE_NAME="$DUMPS_DIR/$fuzz_target.perf"
bash $OUT/$fuzz_target $DUMPS_DIR/$fuzz_target.profdata &
cd $OUT
run_go_fuzz_target $fuzz_target &
else
# Continue if not a fuzz target.
if [[ $FUZZING_ENGINE != "none" ]]; then
Expand Down