summaryrefslogtreecommitdiffstats
path: root/tools/oss-fuzz.sh
blob: 793411ed845de4da3906a802757c35eb9136aa89 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
#!/usr/bin/env bash
# SPDX-License-Identifier: LGPL-2.1-or-later

set -ex

export LC_CTYPE=C.UTF-8

export CC=${CC:-clang}
export CXX=${CXX:-clang++}
clang_version="$($CC --version | sed -nr 's/.*version ([^ ]+?) .*/\1/p' | sed -r 's/-$//')"

SANITIZER=${SANITIZER:-address -fsanitize-address-use-after-scope}
flags="-O1 -fno-omit-frame-pointer -g -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION -fsanitize=$SANITIZER"

clang_lib="/usr/lib64/clang/${clang_version}/lib/linux"
[ -d "$clang_lib" ] || clang_lib="/usr/lib/clang/${clang_version}/lib/linux"

export CFLAGS=${CFLAGS:-$flags}
export CXXFLAGS=${CXXFLAGS:-$flags}
export LDFLAGS=${LDFLAGS:--L${clang_lib}}

export WORK=${WORK:-$(pwd)}
export OUT=${OUT:-$(pwd)/out}
mkdir -p "$OUT"

build="$WORK/build"
rm -rf "$build"
mkdir -p "$build"

if [ -z "$FUZZING_ENGINE" ]; then
    fuzzflag="llvm-fuzz=true"
else
    fuzzflag="oss-fuzz=true"

    apt-get update
    apt-get install -y gperf m4 gettext python3-pip \
        libcap-dev libmount-dev \
        pkg-config wget python3-jinja2 zipmerge

    if [[ "$ARCHITECTURE" == i386 ]]; then
        apt-get install -y pkg-config:i386 libcap-dev:i386 libmount-dev:i386
    fi

    # gnu-efi is installed here to enable -Dgnu-efi behind which fuzz-bcd
    # is hidden. It isn't linked against efi. It doesn't
    # even include "efi.h" because "bcd.c" can work in "unit test" mode
    # where it isn't necessary.
    apt-get install -y gnu-efi zstd

    pip3 install -r .github/workflows/requirements.txt --require-hashes

    # https://github.com/google/oss-fuzz/issues/6868
    ORIG_PYTHONPATH=$(python3 -c 'import sys;print(":".join(sys.path[1:]))')
    export PYTHONPATH="$ORIG_PYTHONPATH:/usr/lib/python3/dist-packages/"

    if [[ "$SANITIZER" == undefined ]]; then
        additional_ubsan_checks=pointer-overflow,alignment
        UBSAN_FLAGS="-fsanitize=$additional_ubsan_checks -fno-sanitize-recover=$additional_ubsan_checks"
        CFLAGS="$CFLAGS $UBSAN_FLAGS"
        CXXFLAGS="$CXXFLAGS $UBSAN_FLAGS"
    fi

    if [[ "$SANITIZER" == introspector ]]; then
        # fuzz-introspector passes -fuse-ld=gold and -flto using CFLAGS/LDFLAGS and due to
        # https://github.com/mesonbuild/meson/issues/6377#issuecomment-575977919 and
        # https://github.com/mesonbuild/meson/issues/6377 it doesn't mix well with meson.
        # It's possible to build systemd with duct tape there using something like
        # https://github.com/google/oss-fuzz/pull/7583#issuecomment-1104011067 but
        # apparently even with gold and lto some parts of systemd are missing from
        # reports (presumably due to https://github.com/google/oss-fuzz/issues/7598).
        # Let's just fail here for now to make it clear that fuzz-introspector isn't supported.
        exit 1
    fi
fi

if ! meson "$build" "-D$fuzzflag" -Db_lundef=false; then
    cat "$build/meson-logs/meson-log.txt"
    exit 1
fi

ninja -v -C "$build" fuzzers

# Compressed BCD files are kept in test/test-bcd so let's unpack them
# and put them all in the seed corpus.
bcd=$(mktemp -d)
for i in test/test-bcd/*.zst; do
     unzstd "$i" -o "$bcd/$(basename "${i%.zst}")";
done
zip -jqr "$OUT/fuzz-bcd_seed_corpus.zip" "$bcd"
rm -rf "$bcd"

hosts=$(mktemp)
wget -O "$hosts" https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts
zip -jq "$OUT/fuzz-etc-hosts_seed_corpus.zip" "$hosts"
rm -rf "$hosts"

# The seed corpus is a separate flat archive for each fuzzer,
# with a fixed name ${fuzzer}_seed_corpus.zip.
for d in test/fuzz/fuzz-*; do
    zip -jqr "$OUT/$(basename "$d")_seed_corpus.zip" "$d"
done

# get fuzz-dns-packet corpus
df="$build/dns-fuzzing"
git clone --depth 1 https://github.com/CZ-NIC/dns-fuzzing "$df"
zip -jqr "$OUT/fuzz-dns-packet_seed_corpus.zip" "$df/packet"

install -Dt "$OUT/src/shared/" \
        "$build"/src/shared/libsystemd-shared-*.so \
        "$build"/src/core/libsystemd-core-*.so

# Most i386 libraries have to be brought to the runtime environment somehow. Ideally they
# should be linked statically but since it isn't possible another way to keep them close
# to the fuzz targets is used here. The dependencies are copied to "$OUT/src/shared" and
# then `rpath` is tweaked to make it possible for the linker to find them there. "$OUT/src/shared"
# is chosen because the runtime search path of all the fuzz targets already points to it
# to load "libsystemd-shared" and "libsystemd-core". Stuff like that should be avoided on
# x86_64 because it tends to break coverage reports, fuzz-introspector, CIFuzz and so on.
if [[ "$ARCHITECTURE" == i386 ]]; then
    for lib_path in $(ldd "$OUT"/src/shared/libsystemd-shared-*.so | perl -lne 'print $1 if m{=>\s+(/lib\S+)}'); do
        lib_name=$(basename "$lib_path")
        cp "$lib_path" "$OUT/src/shared"
        patchelf --set-rpath \$ORIGIN "$OUT/src/shared/$lib_name"
    done
    patchelf --set-rpath \$ORIGIN "$OUT"/src/shared/libsystemd-shared-*.so
fi

wget -O "$OUT/fuzz-json.dict" https://raw.githubusercontent.com/rc0r/afl-fuzz/master/dictionaries/json.dict

find "$build" -maxdepth 1 -type f -executable -name "fuzz-*" -exec mv {} "$OUT" \;
find src -type f -name "fuzz-*.dict" -exec cp {} "$OUT" \;
cp src/fuzz/*.options "$OUT"

if [[ "$MERGE_WITH_OSS_FUZZ_CORPORA" == "yes" ]]; then
    for f in "$OUT/"fuzz-*; do
        [[ -x "$f" ]] || continue
        fuzzer=$(basename "$f")
        t=$(mktemp)
        if wget -O "$t" "https://storage.googleapis.com/systemd-backup.clusterfuzz-external.appspot.com/corpus/libFuzzer/systemd_${fuzzer}/public.zip"; then
            zipmerge "$OUT/${fuzzer}_seed_corpus.zip" "$t"
        fi
        rm -rf "$t"
    done
fi