1. Remove unnecessary includes.
2. Remove thunk function in threaded mode.
3. Inline syscalls into main for the simplest case.
4. Define main in common.h rather than form with printfs.
5. Fix generation for repeat mode
(we had 2 infinite loops: in main and in loop).
6. Remove unused functions (setup/reset_loop, setup/reset_test,
sandbox_namespace, etc).
Make as much code as possible shared between all OSes.
In particular main is now common across all OSes.
Make more code shared between executor and csource
(in particular, loop function and threaded execution logic).
Also make loop and threaded logic shared across all OSes.
Make more posix/unix code shared across OSes
(e.g. signal handling, pthread creation, etc).
Plus other changes along similar lines.
Also support test OS in executor (based on portable posix)
and add 4 arches that cover all execution modes
(fork server/no fork server, shmem/no shmem).
This change paves way for testing of executor code
and allows to preserve consistency across OSes and executor/csource.
We have fallback coverage implmentation for freebsd.
1. It's broken after some recent changes.
2. We need it for fuchsia, windows, akaros, linux too.
3. It's painful to work with C code.
Move fallback coverage to ipc package,
fix it and provide for all OSes.
We see some crashes that suggest corruption of the syscall number:
invalid command number 1296 (errno 11)
invalid command number 107 (errno 110)
Make the table and the number constant to prevent corruption.
We currently have native cross-compilation logic duplicated
in Makefile and in sys/targets. Some pieces are missed in one
place, some are in another. Only pkg/csource knows how to check
for -static support.
Move all CC/CFLAGS logic to sys/targets and pull results in Makefile.
This should make Makefile work on distros that have broken x86_64-linux-gnu-gcc,
now we will use just gcc. And this removes the need to define NOSTATIC,
as it's always auto-detected.
This also paves the way for making pkg/csource work on OSes other than Linux.
gcc8 is stricter when dealing with strings and strncpy and demands that
the size of the actual string to be copied to be explicitly smaller than
the size of the destination, just to make sure the NULL terminator is
taken into considerantion. This patch fixes the issue.
Signed-off-by: Ioana Ciornei <ciorneiioana@gmail.com>
We call the binary syz-executor because it sometimes shows in bug titles,
and we don't want 2 different bugs for when a crash is triggered during
fuzzing and during repro.
Bridge device is used for forwarding. Bond/team device is used for
load balance and fail over. So it would make more sense to add two
slave interfaces for these devices.
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Add a veth pair with name bond/team_slave and set their master
to bond0/team0.
Remove veth from devtypes because the cmd `ip link add veth0 type veth`
will actually failed with "RTNETLINK answers: File exists" and no veth
interface created. When create veth device, kernel will create a
pair of veth, so no need to create them one by one.
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
SYS_memfd_create define produces warning in scource
if system headers already contain the definition (we strip all ifdefs!).
The same is true for CLONE_NEWCGROUP but we just never hit it yet.
Also fix format string for 32 bits.
Also fix potential uninit var in csource, and a missing new line.
Turns out creating a cgroup per test is too expensive.
Moreover, it leads to hanged tasks as cgroup destruction
is asynchronous and overloads kernel work queues.
Create only a single cgroup per proc, but restrict
descriptions to mess with that single group,
instead test processes create own nested cgroups for messing.
There is test failure on travis:
https://travis-ci.org/google/syzkaller/jobs/349948391
I can't reproduce it locally, and it only happened on 1.8, but not on 1.9?
But this seems to be what could have provoked such failure.
We use errno, vaargs, printf in all of fail/error/exitf,
but we include the corresponding headers only when SYZ_USE_TMP_DIR.
Include them whenever fail/error/exitf are used.
The new pseudo syscall allows opening sockets that can only
be created in init net namespace (BLUETOOTH, NFC, LLC).
Use it to open these sockets.
Unfortunately this only works with sandbox none at the moment.
The problem is that setns of a network namespace requires CAP_SYS_ADMIN
in the target namespace, and we've lost all privs in the init namespace
during creation of a user namespace.
We now always create net namespace for testing,
so socket ports and other IDs do not overlap between
different test processes.
Proc types play badly with squashing packets to ANYBLOB.
To squash into a block we need concrete value, but it depends
on process id.
Removing proc also makes tun setup and address descriptions simpler.
Currently when executor creates fd's it gets: 0, 3, 4.
When tun is enabled: 3, 4, 5.
For C programs: 3, 4, 5.
When run is enabled: 4, 5, 6.
Theoretically it should not matter,
but these fd numbers are probably sometimes are used as data.
So make them consistent in all these cases (3, 4, 5).
We currently use -1 as default value for resources
when the actual value is not available.
-1 is good for fd's, but is not the right default
value for pointers/keys/etc.
Pass from prog and use in executor proper default
value for resources.
1. mmap all memory always, without explicit mmap calls in the program.
This makes lots of things much easier and removes lots of code.
Makes mmap not a special syscall and allows to fuzz without mmap enabled.
2. Change address assignment algorithm.
Current algorithm allocates unmapped addresses too frequently
and allows collisions between arguments of a single syscall.
The new algorithm analyzes actual allocations in the program
and places new arguments at unused locations.
Put the underflow entry at the end.
Entries must end on an unconditional, non-goto entry,
otherwise fallthrough from the last entry is invalid.
Add arp tables support.
Split unspec matches/targets to unspec and inet.
Reset ipv6 and arp tables in executor.
Fix number of counters in tables.
Plus a bunch of assorted fixes for matches/targets.
For sandbox=namespace we first create network devices
and then do CLONE_NEWNS, which brings us into a new
namespace which actually does not have any of these devices.
Tun mostly worked, because we hold fd to the tun device.
However, even for tun we could not see the "syz0" device.
We test in a new network namespace, which does not have any
devices set up (even lo). Create/up as many devices as possible.
Give them some addresses and use these addresses in descriptions.
On another machine both clang and gcc produce:
test.c:163:32: error: invalid suffix "+procid" on integer constant
*(uint32_t*)0x20001004 = 0x25dfdbfe+procid*4;
Not sure why this wasn't caught on buildbot.
Remove dup newlines around includes.
Makes int values shorter if not hurting readability.
Increase line len to 80.
Remove {} when not needed during copyout.
The "define uint64_t unsigned long long" were too good to work.
With a different toolchain I am getting:
cstdint:69:11: error: expected unqualified-id
using ::uint64_t;
^
executor/common.h:34:18: note: expanded from macro 'uint64_t'
Do it the proper way: introduce uint64/32/16/8 types and use them.
pkg/csource then does s/uint64/uint64_t/ to not clutter code with
additional typedefs.
Even if all 3 levels of processes in executor exit,
execprog will still recreate them.
Model the same in csource.
This matters when the inner process kills loop
and then everything stops.
I see a crash which says:
#0: too much cover 0 (errno 0)
while the code is:
uint64_t n = ...;
if (n >= kCoverSize)
fail("#%d: too much cover %u", th->id, n);
It seems that the high part of n is set, but we don't see it.
Add printf format attribute to fail and friends and fix all similar cases.
Caught a bunch of similar cases and a missing argument in:
exitf("opendir(%s) failed due to NOFILE, exiting");
Currently csource uses completely different, simpler way of scheduling
syscalls onto threads (thread per call with random sleeps).
Mimic the way calls are scheduled in executor.
Fixes#312
Generated program always uses pid=0 even when there are multiple processes.
Make each process use own pid.
Unfortunately required to do quite significant changes to prog,
because the current format only supported fixed pid.
Fixes#490
We always set RLIMIT_AS to 128MB. I've debugged a program with 21 syscalls.
With collide it creates 42 threads. With default stack size of 8MB this
requires: 42*8 = 336MB. Thread creation fails and nothing works.
Limit thread stacks the same way executor does.
Fixes#488
Factor out program parsing from pkg/csource.
csource code that parses program and at the same time
formats output is very messy and complex.
New aproach also allows to understand e.g.
when a call has copyout instructions which is
useful for better C source output.
csource.go is too large and messy.
Move Build/Format into buid.go.
Move generation of common header into common.go.
Split generation of common header into smaller managable functions.
exitf function was not defined with some combinations of options in csource.
Fix defines and switch exitf back to fail, fail already checks ENOMEM/EAGAIN,
so there is no reason to use exitf in this particular case.
