VM infrastructure currently has several problems:
- Config struct is complete mess with a superset of params for all VM types
- verification of Config is mess spread across several places
- there is no place where VM code could do global initialization
like creating GCE connection, uploading GCE image to GCS,
matching adb devices with consoles, etc
- it hard to add private VM implementations
such impl would need to add code to config package
which would lead to constant merge conflicts
- interface for VM implementation is mixed with interface for VM users
this does not allow to provide best interface for both of them
- there is no way to add common code for all VM implementations
This change solves these problems by:
- splitting VM interface for users (vm package) and VM interface
for VM implementations (vmimpl pacakge), this in turn allows
to add common code
- adding Pool concept that allows to do global initialization
and config checking at the right time
- decoupling manager config from VM-specific config
each VM type now defines own config
Note: manager configs need to be changed after this change:
VM-specific parts are moved to own "vm" subobject.
Note: this change also drops "local" VM type.
Its story was long unclear and there is now syz-stress which solves the same problem.
syz-fuzzer never exits (normally) so this does not affect syz-manager.
But during reproduction we can run a short running program (no repeat mode)
and currently VMs treat premature exit as an error.
Properly detect when a program exits and let callers decide what to do with it.
create-image.sh tries to enable eth0 network interface of the virtual machine,
but there is no eth0 in a fresh debian-wheezy, since biosdevname renames interfaces.
VM log quotation:
e1000 0000:00:03.0 eth0: (PCI:33MHz:32-bit) 52:54:00:12:34:56
e1000 0000:00:03.0 eth0: Intel(R) PRO/1000 Network Connection
e1000 0000:00:03.0 ens3: renamed from eth0
...
Cannot find device "eth0"
Bind socket to interface: No such device
Failed to bring up eth0.
The simplest fix is disabling biosdevname by adding "net.ifnames=0 biosdevname=0"
to the kernel command line.
Signed-off-by: Alexander Popov <alex.popov@linux.com>
Add config bin_args parameter that contains additional arguments for qemu binary.
This allows to specify e.g. "bin_args": "-machine virt -cpu cortex-a57".
Also restore qemu debugging output when -debug flag is specified.
When we recover from a transient failure, we want to cleanup
everything except for the workdir, because we will use it again
during next VM creation attempt.
Currently the next attempt always fails.
If "image" is set to "9p" in config file,
qemu VM will create a minimalistic image based
on readonly-mapped host filesystem.
The main things that we need are working sshd and ssh-keygen.
/tmp, /etc/, /var, /root are remounted as tmpfs.
Rebooting only confuses syz-manager as it thinks that it's the same
dirty instance. Let syz-manager recreate the VM from scratch instead.
-display=none does not disable graphics subsystem which may be useful for fuzzing.
It also seems to be newer than -nographics.
This patch sets the ssh loglevel to error to avoid noisy warnings, specifically
known host errors like:
Warning: Permanently added '[localhost]:1569' (ECDSA) to the list of known hosts.
Previously this appeared at the top of every crash report.
Current interface is suitable only for running syz-fuzzer.
Make the interface more generic (boot, copy file, run an arbitrary command).
This allows to build other tools on top of vm package
(e.g. reproducer creation).
Remove master process entirely, it is not useful in its current form.
We first need to understand what we want from it, and them re-implement it.
Prefix all binaries with syz- to avoid name clashes.
If you set "leak":true in manager config, it will do leak checking.
It's quite slow, though. Also there seems to be false positives
and/or non-reproducible leaks.
