From 54c9e41d47daa38219a53311cbc1c4e602709aee Mon Sep 17 00:00:00 2001 From: Alexander Bulekov Date: Wed, 2 Sep 2020 13:36:51 -0400 Subject: [PATCH] fuzz: Add support for custom fuzzing library On oss-fuzz, we must use the LIB_FUZZING_ENGINE and CFLAGS environment variables, rather than -fsanitize=fuzzer. With this change, when LIB_FUZZING_ENGINE is set, the --enable-fuzzing configure option will use that environment variable during the linking stage, rather than -fsanitize=fuzzer Signed-off-by: Alexander Bulekov Message-Id: <20200902173652.307222-3-alxndr@bu.edu> Signed-off-by: Paolo Bonzini --- configure | 12 ++++++++++-- tests/qtest/fuzz/meson.build | 4 ++-- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/configure b/configure index ba8c6e6c5d..53723ace57 100755 --- a/configure +++ b/configure @@ -6048,7 +6048,7 @@ fi ########################################## # checks for fuzzer -if test "$fuzzing" = "yes" ; then +if test "$fuzzing" = "yes" && test -z "${LIB_FUZZING_ENGINE+xxx}"; then write_c_fuzzer_skeleton if compile_prog "$CPU_CFLAGS -Werror -fsanitize=fuzzer" ""; then have_fuzzer=yes @@ -7354,7 +7354,14 @@ if test "$have_mlockall" = "yes" ; then echo "HAVE_MLOCKALL=y" >> $config_host_mak fi if test "$fuzzing" = "yes" ; then - QEMU_CFLAGS="$QEMU_CFLAGS -fsanitize=fuzzer-no-link" + # If LIB_FUZZING_ENGINE is set, assume we are running on OSS-Fuzz, and the + # needed CFLAGS have already been provided + if test -z "${LIB_FUZZING_ENGINE+xxx}" ; then + QEMU_CFLAGS="$QEMU_CFLAGS -fsanitize=fuzzer-no-link" + FUZZ_EXE_LDFLAGS="-fsanitize=fuzzer" + else + FUZZ_EXE_LDFLAGS="$LIB_FUZZING_ENGINE" + fi fi if test "$plugins" = "yes" ; then @@ -7455,6 +7462,7 @@ fi if test "$fuzzing" != "no"; then echo "CONFIG_FUZZ=y" >> $config_host_mak fi +echo "FUZZ_EXE_LDFLAGS=$FUZZ_EXE_LDFLAGS" >> $config_host_mak if test "$edk2_blobs" = "yes" ; then echo "DECOMPRESS_EDK2_BLOBS=y" >> $config_host_mak diff --git a/tests/qtest/fuzz/meson.build b/tests/qtest/fuzz/meson.build index bcc393828e..b31ace7d5a 100644 --- a/tests/qtest/fuzz/meson.build +++ b/tests/qtest/fuzz/meson.build @@ -7,8 +7,8 @@ specific_fuzz_ss.add(when: 'CONFIG_VIRTIO_NET', if_true: files('virtio_net_fuzz. specific_fuzz_ss.add(when: 'CONFIG_VIRTIO_SCSI', if_true: files('virtio_scsi_fuzz.c')) fork_fuzz = declare_dependency( - link_args: ['-fsanitize=fuzzer', - '-Wl,-wrap,qtest_inb', + link_args: config_host['FUZZ_EXE_LDFLAGS'].split() + + ['-Wl,-wrap,qtest_inb', '-Wl,-wrap,qtest_inw', '-Wl,-wrap,qtest_inl', '-Wl,-wrap,qtest_outb',