41 Commits

Author SHA1 Message Date
Dmitry Vyukov
52a33fd516 prog: remove default target and all global state
Now each prog function accepts the desired target explicitly.
No global, implicit state involved.
This is much cleaner and allows cross-OS/arch testing, etc.
2017-09-15 16:02:37 +02:00
Dmitry Vyukov
ffe7e17368 prog, sys: move types to prog
Large overhaul moves syscalls and arg types from sys to prog.
Sys package now depends on prog and contains only generated
descriptions of syscalls.
Introduce prog.Target type that encapsulates all targer properties,
like syscall list, ptr/page size, etc. Also moves OS-dependent pieces
like mmap call generation from prog to sys.

Update #191
2017-09-05 15:52:42 +02:00
Dmitry Vyukov
4fc4702694 prog: dot-import sys
In preparation for moving sys types to prog to reduce later diffs.
2017-09-05 10:46:34 +02:00
Dmitry Vyukov
1c0d4caf7c sys: change BitfieldLast to BitfieldMiddle
That's the condition we always want.
Currently we always check:
t.BitfieldOffset() == 0 || t.BitfieldLast()
now can check just:
!t.BitfieldMiddle()
2017-09-04 20:51:56 +02:00
Dmitry Vyukov
399addc875 sys, pkg/compiler: move padding computation to compiler
This makes types constant during execution, everything is precomputed.
2017-09-04 20:25:23 +02:00
Dmitry Vyukov
838e336594 sys, prog: switch values to to uint64
We currently use uintptr for all values.
This won't work for 32-bit archs.
Moreover in some cases we use uintptr but assume
that it is always 64-bits (e.g. in encodingexec).
Switch everything to uint64.

Update #324
2017-08-19 10:16:23 +02:00
Andrey Konovalov
cfc46d9d0b prog: split Arg into smaller structs
Right now Arg is a huge struct (160 bytes), which has many different fields
used for different arg kinds. Since most of the args we see in a typical
corpus are ArgConst, this results in a significant memory overuse.

This change:
- makes Arg an interface instead of a struct
- adds a SomethingArg struct for each arg kind we have
- converts all *Arg pointers into just Arg, since interface variable by
  itself contains a pointer to the actual data
- removes ArgPageSize, now ConstArg is used instead
- consolidates correspondence between arg kinds and types, see comments
  before each SomethingArg struct definition
- now LenType args that denote the length of VmaType args are serialized as
  "0x1000" instead of "(0x1000)"; to preserve backwards compatibility
  syzkaller is able to parse the old format for now
- multiple small changes all over to make the above work

After this change syzkaller uses twice less memory after deserializing a
typical corpus.
2017-07-17 14:34:09 +02:00
Andrey Konovalov
b3ea23c379 repro: always minimize over EnableTun 2017-06-12 19:48:23 +02:00
Andrey Konovalov
4d1df73af9 csource: force enable tun flag when required 2017-06-12 19:48:23 +02:00
Andrey Konovalov
ac0c70f74a prog, executor: move checksum computation to executor
This commit moves checksum computation to executor. This will allow to embed
dynamically generated values (like TCP sequence numbers) into packets.
2017-05-12 15:47:59 +02:00
Dmitry Vyukov
bba1519958 prog: fix mknod sanitization
mknod mode also includes ownership flags, so filter out the node type.
Also allow creation of loop nodes.
Remove mount$fs as it does not seem to make any sense.
2017-02-14 11:56:41 +01:00
Andrey Konovalov
63b16a5d5c prog, sys: add csum type, embed checksums for ipv4 packets
This change adds a `csum[kind, type]` type.
The only available kind right now is `ipv4`.
Using `csum[ipv4, int16be]` in `ipv4_header` makes syzkaller calculate
and embed correct checksums into ipv4 packets.
2017-01-25 20:31:13 +01:00
Andrey Konovalov
c8d03a05f3 prog: move size-related functions to size.go 2017-01-25 16:33:37 +01:00
Andrey Konovalov
1cf6a05e0e sys, prog: add length of parent of parent to templates
Example:
```
struct s1 {
	f0	len[s2] # length of s2
}

struct s2 {
	f0	s1
	f1	array[int32]
}
```
2017-01-23 18:13:11 +01:00
Andrey Konovalov
b323c5aaa9 prog: add FieldName to Type
FieldName() is the name of the struct field or union option with this type.
TypeName() is now always the name of the type.
2017-01-23 18:13:06 +01:00
Andrey Konovalov
243c4bf89c prog: fix bytesizeN for nonarray fields 2017-01-19 20:46:26 +01:00
Andrey Konovalov
8625843eeb prog: fix calculating parent length in struct with bitfields 2017-01-19 20:46:26 +01:00
Dmitry Vyukov
c377a6514d prog: reformat source 2017-01-09 20:26:34 +01:00
Andrey Konovalov
df98b6bde5 prog: add bytesizeN types 2016-12-20 18:12:07 +01:00
Dmitry Vyukov
578ee4fa8d prog: sanitize mknodat the same way as mknod 2016-11-18 10:24:13 +01:00
Dmitry Vyukov
8b731ed4b7 sys: replace FilenameType with BufferType{Kind: BufferFilename}
FilenameType is effectively a buffer, there is no need for a separate type.
2016-11-11 14:32:19 -08:00
Dmitry Vyukov
b40d502736 prog: remote Type argument from Arg.Size/Value
They are not necessary since we now always have types attached to args.
Also remove sys.Type.InnerType as it is not necessary now as well.
2016-11-11 14:31:55 -08:00
Dmitry Vyukov
1838728cc1 prog: simplify assignSizes
Now that we always have types attached to args,
assignSizes can be considerably simplified.
2016-11-11 14:30:20 -08:00
Dmitry Vyukov
1a85811d68 prog: assign types to args during construction
Eliminate assignTypeAndDir function and instead assign
types to all args during construction.
This will allow considerable simplifation of assignSizes.
2016-11-11 14:29:52 -08:00
Dmitry Vyukov
d3a93e8370 sys: attach Dir to all types
Dir is a static info, so we don't need to compute, propagate and
attach it in prog whenever we generate/change programs.
Attach Dir to all types.
2016-11-11 14:27:54 -08:00
Dmitry Vyukov
959ec07095 sys: always use pointers to types
Currently we store most types by value in sys.Type.
This is somewhat counter-intuitive for C++ programmers,
because one can't easily update the type object.
Store pointers to type objects for all types.
It also makes it easier to update types, e.g. adding paddings.
2016-11-11 14:25:13 -08:00
Andrey Konovalov
78f79fee93 Refactor & improve len type handling 2016-10-11 20:09:19 +02:00
Dmitry Vyukov
852e3d2eae sys: support recursive structs
A struct can have a pointer to itself directly or indirectly.
Currently it leads to inifinite recursion when generating descriptions.
Fix this.
2016-09-05 12:49:47 +02:00
Dmitry Vyukov
7690667267 sys: specify resources in text descriptions
Currently to add a new resource one needs to modify multiple source files,
which complicates descirption of new system calls.
Move resource descriptions from source code to text desciptions.
2016-08-27 18:27:50 +02:00
Dmitry Vyukov
0d0fbbe73f overhaul syscall description generation process
This splits generation process into two phases:
1. Extract values of constants from linux kernel sources.
2. Generate Go code.

Constant values are checked in.
The advantage is that the second phase is now completely independent
from linux source files, kernel version, presence of headers for
particular drivers, etc. This allows to change what Go code we generate
any time without access to all kernel headers (which in future won't be
limited to only upstream headers).

Constant extraction process does require proper kernel sources,
but this can be done only once by the person who added the driver
and has access to the required sources. Then the constant values
are checked in for others to use.
Consant extraction process is per-file/per-arch. That is,
if I am adding a driver that is not present upstream and that
works only on a single arch, I will check in constants only for
that driver and for that arch.
2016-08-26 07:09:25 +02:00
Dmitry Vyukov
e7021ac638 prog: don't try to execute ioctl(FIFREEZE) and mknod
ioctl(FIFREEZE) renders machine dead.
FIFREEZE is an interesting thing, and we could test it
in namespace (?) or on manually mounted file systems (?).
But that will require more complex handling.
Disable it until we have that logic.

mknod of char/block devices can do all kinds of nasty stuff
(read/write to IO ports, kernel memory, etc).
Disable it for now.
2016-08-21 18:07:55 -07:00
Dmitry Vyukov
9c277c7974 sys: describe more dri syscalls 2016-01-16 00:23:47 +01:00
Dmitry Vyukov
4eb9d403e8 prog: implement mutation of union args 2015-12-31 16:03:01 +01:00
Dmitry Vyukov
e6529b30ec sys: add union type 2015-12-29 15:00:57 +01:00
Dmitry Vyukov
9980a72713 sys: automatically add padding to structs 2015-12-17 14:38:46 +01:00
Dmitry Vyukov
6892001bbc add tty-related ioctl's 2015-11-16 19:14:05 +01:00
Dmitry Vyukov
b0a24e2466 don't generate pthread(PTRACE_TRACEME) due to a known issue 2015-10-20 15:46:04 +02:00
Dmitry Vyukov
f8f416fb8f preliminary description of kdbus syscalls 2015-10-16 18:16:10 +02:00
Dmitry Vyukov
c9b915608d initial support for call priorities 2015-10-14 16:55:09 +02:00
Dmitry Vyukov
8b78c985ab support iocb pointers as resources 2015-10-13 20:13:40 +02:00
Dmitry Vyukov
874c5754bb initial commit 2015-10-12 10:16:57 +02:00