For information about checking out and building Fuchsia see Getting Started and Source Code.
To run syzkaller with a fuchsia target, you will need:
- A fuchsia checkout.
The rest of the document will use the following environment variables:
SOURCEDIR
path of your fuchsia checkout.
To build fuchsia run:
$ fx --dir "out/arm64" set core.arm64 \
--with-base "//bundles:tools" \
--with-base "//src/testing/fuzzing/syzkaller" \
--args=syzkaller_dir='"/full/path/to/syzkaller"'
$ fx clean-build
And
$ fx --dir "out/x64" set core.x64 \
--with-base "//bundles:tools" \
--with-base "//src/testing/fuzzing/syzkaller" \
--args=syzkaller_dir='"/full/path/to/syzkaller"'
$ fx clean-build
To build all the binaries required for running syzkaller in fuchsia, run:
$ make TARGETOS=fuchsia TARGETARCH=amd64 \
SOURCEDIR=path/to/fuchsia/checkout
Running syz-manager requires you to have built fuchsia previously, and added the ssh keys to the fuchsia.zbi image:
$ ${SOURCEDIR}/out/x64.zircon/tools/zbi -o ${SOURCEDIR}/out/x64/fuchsia-ssh.zbi ${SOURCEDIR}/out/x64/fuchsia.zbi --entry "data/ssh/authorized_keys=${SOURCEDIR}/.ssh/authorized_keys"
Note: This needs to be repeated after each fx build
.
Run syz-manager
with a config along the lines of:
{
"name": "fuchsia",
"target": "fuchsia/amd64",
"http": ":12345",
"workdir": "/workdir.fuchsia",
"kernel_obj": "/fuchsia/out/x64.zircon/kernel-x64-gcc",
"syzkaller": "/syzkaller",
"image": "/fuchsia/out/x64/obj/build/images/fvm.blk",
"sshkey": "/fuchsia/.ssh/pkey",
"reproduce": false,
"cover": false,
"procs": 8,
"type": "qemu",
"vm": {
"count": 10,
"cpu": 4,
"mem": 2048,
"kernel": "/fuchsia/out/x64.zircon/multiboot.bin",
"initrd": "/fuchsia/out/x64/fuchsia-ssh.zbi"
}
}
Syscall descriptions live in the sys/fuchsia
folder. To update a syscall, you need to modify the .txt
file that contains it, make sure your new definition matches the one in zircon's syscalls.abigen file. If the syscall was used in executor/common_fuchsia.h
, you need to update the usages there as well. FIDL definitions do not need manual updating because they are extracted automatically when you run make extract
, but they require Fuchsia to be rebuilt for each architecture (see "Building Fuchsia" above).
Once you updated the syscalls definitions, everything can be regenerated by running:
make extract TARGETOS=fuchsia SOURCEDIR=/path/to/fuchsia/checkout
make generate
TODO: This section is out of date.
Syscall descriptions for FIDL are automatically generated as part of make extract
as described above.
However, if you wish to manually generate syscall descriptions for a given .fidl
file, do the following.
FIDL files should first be compiled into FIDL intermediate representation (JSON) files using fidlc
:
$SOURCEDIR/out/x64/host_x64/fidlc --json /tmp/io.json --files $SOURCEDIR/zircon/system/fidl/fuchsia-io/io.fidl
Then run FIDL compiler backend fidlgen
with syzkaller generator, which compiles a FIDL IR file into a syscall description file:
$SOURCEDIR/out/x64/host_x64/fidlgen -generators syzkaller -json /tmp/io.json -output-base fidl_io -include-base fidl_io
To run syz-ci
locally for Fuchsia, you need:
- bootstrapped Fuchsia checkout (in
/bootstrap/fuchsia
dir in the example below) - bootstrap
syz-ci
binary (in the current dir, build withmake ci
) syz-ci
config similar to the one below (inci.cfg
file in the current dir)
{
"name": "testci",
"http": ":50000",
"manager_port_start": 50001,
"syzkaller_repo": "https://github.com/google/syzkaller.git",
"managers": [
{
"name": "fuchsia",
"repo": "https://fuchsia.googlesource.com",
"manager_config": {
"target": "fuchsia/amd64",
"type": "qemu",
"cover": false,
"procs": 8,
"vm": {
"count": 4,
"cpu": 4,
"mem": 1024
}
}
}
]
}
Run syz-ci
as:
SOURCEDIR=/bootstrap/fuchsia ./syz-ci -config ci.cfg
While running the make extract
step, it's possible that the fidl definitions
are not up to date. It could happen that they have been removed or renamed.
If this is the case, you would see an error mentioning that the fidl.json file could not be found:
go generate ./sys/fuchsia
cannot find /path-to-fuchsia/out/x64/fidling/gen/zircon/public/fidl/zircon-ethernet/zircon-ethernet.fidl.json
exit status 1
You can search for the string in the fuchsia repos or in the code-review tool to
see what happened to it. If the fidl interface was renamed or removed, you
should update sys/fuchsia/fidlgen/main.go
to reflect this change, and remove the
stale autogenerated files.