Commit Graph

29 Commits

Author SHA1 Message Date
Dmitry Vyukov
645e75f803 executor: make syscall table and number constant
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.
2018-06-07 15:32:30 +02:00
Dmitry Vyukov
cda1fcb742 sys: dedup mmap code across OSes
Update #538
2018-05-06 16:58:38 +02:00
Dmitry Vyukov
31ea20ce83 sys: move generate files to separate packages
Move generated files to gen subdir. This allows to:
1. Rebuild init.go without rebuilding generated code.
2. Excluding generated files from gometalinter checking.
This makes faster and consume less memory.

Update #538
2018-05-05 15:40:10 +02:00
Dmitry Vyukov
4c24e4a467 gometalinter: enable package comment checking
Update #538
2018-05-03 13:53:01 +02:00
Dmitry Vyukov
70a1ddb939 prog: harden program parsing against description changes more
Handle most of type changes, e.g. const is changed to struct,
or struct to pointers. In all these cases we create default args.
They may not give the coverage anymore, but still better than
losing them right away.
2018-03-05 12:10:27 +01:00
Dmitry Vyukov
bd5df8f49b prog: handle excessive args and fields during program parsing
Tolerate excessive args and fields during program parsing.
This is useful after description changes to not lose corpus.
2018-03-05 12:10:27 +01:00
Dmitry Vyukov
002cecf202 pkg/compiler: allow specifying static size for filename's
Sometimes filenames are embed into structs and need to take fixed space.
2018-03-05 12:10:27 +01:00
Dmitry Vyukov
5ef8dbdf5a pkg/compiler: support size attribute for unions 2018-03-05 12:10:27 +01:00
Dmitry Vyukov
a339951e5f pkg/compiler: add size attribute for structs
The size attribute allows to pad a struct up to the specified size.
2018-03-05 12:10:27 +01:00
Dmitry Vyukov
6284466bc9 prog: properly squash bitfields 2018-02-26 18:21:51 +01:00
Dmitry Vyukov
9fe8aa42c5 prog: add arbitrary mutation of complex structs
Squash complex structs into flat byte array and mutate this array
with generic blob mutations. This allows to mutate what we currently
consider as paddings and add/remove paddings from structs, etc.
2018-02-25 18:22:02 +01:00
Dmitry Vyukov
2145057cb8 pkg/compiler: fix alignment corner case
Fix alignemnt calculation for packed structs with alignment and bitfields.
Amusingly this affected only a single real struct -- ipv6_fragment_ext_header.
2018-02-25 14:44:29 +01:00
Dmitry Vyukov
1f4ae3f413 pkg/compiler: don't assign call IDs statically
IDs change whenever a call is added or removed,
this leads to large diffs unnecessarly.
Assign IDs dynamically.
2018-02-25 14:31:40 +01:00
Dmitry Vyukov
7a7c747c6f pkg/compiler: allow unions as syscall arguments
If all union options can be syscall arguments,
allow the union itself as syscall argument.
2018-02-23 13:50:02 +01:00
Dmitry Vyukov
a793204dd2 pkg/compiler: fix corner case in alignment calculation 2018-02-19 21:48:20 +01:00
Dmitry Vyukov
75a7c5e2d1 prog: rework address allocation
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.
2018-02-19 21:48:20 +01:00
Dmitry Vyukov
dd4fcef5a2 pkg/compiler: allow len of var-len arrays
All netfilter subsystems use this unfortunately,
so demote this to a warning.
2018-02-17 19:02:12 +01:00
Dmitry Vyukov
e8b4970547 pkg/compiler: allow unions with only 1 field
Unions with only 1 field are not actually unions,
and can always be replaced with the option type.
However, they are still useful when there will be
more options in future but currently only 1 is described.
Alternatives are:
 - not using union (but then all existing programs will be
   broken when union is finally introduced)
 - adding a fake field (ugly and reduces fuzzer efficiency)

Allow unions with only 1 field.
2018-01-27 17:08:43 +01:00
Dmitry Vyukov
ca9c302d80 pkg/compiler, prog: fix template parent lens
It's possible that a struct can have 2+ parents,
which is the same template (differs only by arguments).
See the new test case.
Support such case.
2018-01-24 11:35:22 +01:00
Dmitry Vyukov
3d76cc40d9 pkg/compiler: fix len of parent template struct
Consider the following example:

type len_templ1[DATA1, DATA2] {
	data	DATA1
	inner	len_temp2[DATA2]
}

type len_temp2[DATA] {
	data	DATA
	len	len[len_templ1, int8]
}

Here len refers to a parent struct, but the struct is a template,
so it's actual name is something like "len_templ1[int8, int16]".
Currently this does not work as compiler barks at incorrect
len target.

Make this work.
2018-01-23 11:38:53 +01:00
Dmitry Vyukov
a94baff95e sys/syz-sysgen: don't generate syz_ syscall numbers
They don't seem to be used today.
2018-01-13 12:52:09 +01:00
Dmitry Vyukov
5585946e22 pkg/compiler: support void type
"void": type with static size 0
	mostly useful inside of templates and varlen unions
	can't be syscall argument
2018-01-13 12:52:09 +01:00
Dmitry Vyukov
a8927abe6c prog: support opt for proc types 2018-01-06 17:40:49 +01:00
Dmitry Vyukov
8a67aa70b0 prog: add test for len mutation
Test we actually can get an unnatural len value.
2018-01-06 17:40:43 +01:00
Dmitry Vyukov
8e6b9eeb27 pkg/compiler: add bitsize type
This is need for few crypto/xfrm descriptions.
2018-01-06 17:40:36 +01:00
Dmitry Vyukov
8ef0050706 prog: don't serialize output data args
Fixes #188

We now will write just ""/1000 to denote a 1000-byte output buffer.
Also we now don't store 1000-byte buffer in memory just to denote size.
Old format is still parsed.
2017-12-17 11:39:14 +01:00
Dmitry Vyukov
41799debdc prog: introduce more readable format for data args
Fixes #460

File names, crypto algorithm names, etc in programs are completely unreadable:

bind$alg(r0, &(0x7f0000408000)={0x26, "6861736800000000000000000000",
0x0, 0x0, "6d6435000000000000000000000000000000000000000000000000
000000000000000000000000000000000000000000000000000000000000000
00000000000"}, 0x58)

Introduce another format for printable strings.
New args are denoted by '' ("" for old args).
New format is enabled for printable chars, \x00
and \t, \r, \n.

Example:
`serialize(&(0x7f0000408000)={"6861736800000000000000000000", "4849000000"})`,
vs:
`serialize(&(0x7f0000408000)={'hash\x00', 'HI\x00'})`,
2017-12-17 11:39:14 +01:00
Dmitry Vyukov
286edfb78e prog: fix TestMutateTable
Now works fast enough even for short mode.

Fixes #208
2017-12-17 11:39:14 +01:00
Dmitry Vyukov
019cf5f235 sys: move test syscalls to a separate target
We have them in linux solely for historical reasons.

Fixes #462
2017-12-17 11:39:14 +01:00