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Kirill Smelkov 75118780da tccrun: Mark argv area as valid for bcheck
On my x86_64 box in i386 mode with address space randomization turned off,
I've observed the following:

    tests$ ../tcc -B.. -b -run boundtest.c 1
    Runtime error: dereferencing invalid pointer
    boundtest.c:222: at 0x808da73 main()

With diagnostic patch (like in efd9d92b "lib/bcheck: Don't assume heap
goes right after bss") and bcheck traces for __bound_new_region,
__bound_ptr_indir, etc... here is how the program run looks like:

    >>> TCC

    etext:   0x8067ed8
    edata:   0x807321d
    end:     0x807d95c
    brk:     0x807e000
    stack:  0xffffd0b4
    &errno: 0xf7dbd688
    mark_invalid  0xfff80000 -      (nil)
    mark_invalid   0x80fa000 - 0x100fa000
    new  808fdb0  808ff40  101  101  fd0  ff0
    new  808ff44  808ff48  101  101  ff0  ff0
    new  808ff49  8090049  101  101  ff0 1000
    new  808fd20  808fd29  101  101  fd0  fd0
    new  808fd2c  808fd6c  101  101  fd0  fd0
    new  808fd6d  808fda0  101  101  fd0  fd0
    E: __bound_ptr_indir4(0xffffd184, 0x4)
    Runtime error: dereferencing invalid pointer
    boundtest.c:222: at 0x808ea83 main()

So we are accessing something on stack, above stack entry for compiled
main. Investigating with gdb shows that this is argv:

    tests$ gdb ../tcc
    Reading symbols from /home/kirr/src/tools/tinycc/tcc...done.
    (gdb) set args -B.. -b -run boundtest.c 1
    (gdb) r
    Starting program: /home/kirr/src/tools/tinycc/tests/../tcc -B.. -b -run boundtest.c 1
    warning: Could not load shared library symbols for linux-gate.so.1.
    Do you need "set solib-search-path" or "set sysroot"?

    >>> TCC

    etext:   0x8067ed8
    edata:   0x807321d
    end:     0x807d95c
    brk:     0x807e000
    stack:  0xffffd074
    &errno: 0xf7dbd688
    mark_invalid  0xfff80000 -      (nil)
    mark_invalid   0x80fa000 - 0x100fa000
    new  808fdb0  808ff40  101  101  fd0  ff0
    new  808ff44  808ff48  101  101  ff0  ff0
    new  808ff49  8090049  101  101  ff0 1000
    new  808fd20  808fd29  101  101  fd0  fd0
    new  808fd2c  808fd6c  101  101  fd0  fd0
    new  808fd6d  808fda0  101  101  fd0  fd0
    E: __bound_ptr_indir4(0xffffd144, 0x4)

    Program received signal SIGSEGV, Segmentation fault.
    0x0808ea83 in ?? ()
    (gdb) bt
    #0  0x0808ea83 in ?? ()
    #1  0x080639b3 in tcc_run (s1=s1@entry=0x807e008, argc=argc@entry=2, argv=argv@entry=0xffffd144) at tccrun.c:132
    #2  0x080492b0 in main (argc=6, argv=0xffffd134) at tcc.c:346
    (gdb) f 1
    #1  0x080639b3 in tcc_run (s1=s1@entry=0x807e008, argc=argc@entry=2, argv=argv@entry=0xffffd144) at tccrun.c:132
    132             ret = (*prog_main)(argc, argv);
    132             ret = (*prog_main)(argc, argv);
    (gdb) p argv
    $1 = (char **) 0xffffd144

So before running compiled program, mark argv as valid region and we are
done - now the test passes.

P.S. maybe it would be better to just mark the whole vector kernel passes to
program (argv, env, auxv, etc...) as valid all at once...
2014-01-19 16:47:51 +04:00
examples Revert "Make ex1.c and ex4.c be executable on any systems" 2012-06-12 15:45:13 +02:00
include Fixed the LDBL_* macros in include/float.h for x86-64: as said 2014-01-12 22:26:09 +01:00
lib misc. fixes 2014-01-06 19:56:26 +01:00
tests tcctest: One more signed zero test 2014-01-12 04:53:29 +01:00
win32 misc. fixes 2014-01-06 19:56:26 +01:00
.gitignore make git ignore lib/arm directory 2013-12-15 09:49:20 +08:00
arm-gen.c Fix compile on ARM non-eabi and non-vfp 2014-01-11 23:44:41 +01:00
c67-gen.c Fix struct ret in variadic fct with ARM hardfloat 2014-01-06 22:57:05 +08:00
Changelog Add support for runtime selection of float ABI 2014-01-08 15:00:52 +08:00
CMakeLists.txt Use GNU triplet prefix for cross tcc compilers 2014-01-08 21:07:59 +08:00
coff.h add version number to manpage 2013-02-17 00:48:51 +01:00
config.h.in Improved variable length array support. 2013-04-27 22:58:52 +01:00
config.texi.in Added cross compilation to CMake build system. 2013-04-25 01:08:18 +01:00
configure be stricter with aliasing 2014-01-07 14:57:07 +01:00
conftest.c Add arm ABI detection in conftest.c 2013-02-14 16:40:16 +01:00
COPYING changed license to LGPL 2003-05-24 14:18:56 +00:00
elf.h Update elf.h 2014-01-08 17:38:31 +08:00
i386-asm.c Detect correct instruction with incorrect operands 2013-09-24 15:37:11 +02:00
i386-asm.h Detect correct instruction with incorrect operands 2013-09-24 15:37:11 +02:00
i386-gen.c be stricter with aliasing 2014-01-07 14:57:07 +01:00
i386-tok.h integrate x86_64-asm.c into i386-asm.c 2009-12-19 22:16:20 +01:00
il-gen.c Fix struct ret in variadic fct with ARM hardfloat 2014-01-06 22:57:05 +08:00
il-opcodes.h added CIL target 2002-02-10 16:14:03 +00:00
libtcc.c Add support for runtime selection of float ABI 2014-01-08 15:00:52 +08:00
libtcc.h libtcc: new LIBTCCAPI tcc_set_options(TCCState*, const char*str) 2013-02-12 19:13:28 +01:00
Makefile Various Makefile fixes for cross-compilation 2014-01-09 17:15:08 +08:00
README Fix building instruction wrt make/gmake 2013-04-08 23:26:27 +02:00
RELICENSING Relicensing TinyCC 2014-01-04 15:35:26 +01:00
stab.def added 2002-12-08 14:36:36 +00:00
stab.h added 2002-12-08 14:36:36 +00:00
tcc-doc.texi Add support for runtime selection of float ABI 2014-01-08 15:00:52 +08:00
tcc.c Add support for runtime selection of float ABI 2014-01-08 15:00:52 +08:00
tcc.h Add support for runtime selection of float ABI 2014-01-08 15:00:52 +08:00
tccasm.c configure: cleanup 2013-02-14 06:53:07 +01:00
tcccoff.c portability: fix void* <-> target address conversion confusion 2013-02-04 16:24:59 +01:00
tccelf.c Remove WITHOUT_LIBTCC macro: no more user 2014-01-08 21:32:53 +08:00
tccgen.c Fix floating point unary minus and plus 2014-01-12 04:44:27 +01:00
tcclib.h Sorted out CMake on x86-64 and fixed silly XMM# bug introduced when working on Win64 stdargs. 2013-04-25 22:30:53 +01:00
tccpe.c tccpe: cleanup "imports per ordinal" 2014-01-06 19:32:50 +01:00
tccpp.c misc. fixes 2014-01-06 19:56:26 +01:00
tccrun.c tccrun: Mark argv area as valid for bcheck 2014-01-19 16:47:51 +04:00
tcctok.h i386: use __fixdfdi instead of __tcc_cvt_ftol 2014-01-06 19:07:08 +01:00
texi2pod.pl automatic man page generation from tcc-doc.texi 2003-05-18 18:11:06 +00:00
TODO remove doubled prototype 2013-02-18 15:44:18 +01:00
VERSION Release TinyCC 0.9.26 2013-02-15 14:23:58 +01:00
x86_64-asm.h Detect correct instruction with incorrect operands 2013-09-24 15:37:11 +02:00
x86_64-gen.c be stricter with aliasing 2014-01-07 14:57:07 +01:00

Tiny C Compiler - C Scripting Everywhere - The Smallest ANSI C compiler
-----------------------------------------------------------------------

Features:
--------

- SMALL! You can compile and execute C code everywhere, for example on
  rescue disks.

- FAST! tcc generates optimized x86 code. No byte code
  overhead. Compile, assemble and link about 7 times faster than 'gcc
  -O0'.

- UNLIMITED! Any C dynamic library can be used directly. TCC is
  heading torward full ISOC99 compliance. TCC can of course compile
  itself.

- SAFE! tcc includes an optional memory and bound checker. Bound
  checked code can be mixed freely with standard code.

- Compile and execute C source directly. No linking or assembly
  necessary. Full C preprocessor included. 

- C script supported : just add '#!/usr/local/bin/tcc -run' at the first
  line of your C source, and execute it directly from the command
  line.

Documentation:
-------------

1) Installation on a i386/x86_64/arm Linux/OSX/FreeBSD host (for Windows read tcc-win32.txt)

Note: For OSX and FreeBSD, gmake should be used instead of make.

   ./configure
   make
   make test
   make install

Alternatively, out-of-tree builds are supported: you may use different
directories to hold build objects, kept separate from your source tree:

   mkdir _build
   cd _build
   ../configure
   make
   make test
   make install

Texi2html must be installed to compile the doc. 
By default, tcc is installed in /usr/local/bin.
./configure --help  shows configuration options.


2) Introduction

We assume here that you know ANSI C. Look at the example ex1.c to know
what the programs look like.

The include file <tcclib.h> can be used if you want a small basic libc
include support (especially useful for floppy disks). Of course, you
can also use standard headers, although they are slower to compile.

You can begin your C script with '#!/usr/local/bin/tcc -run' on the first
line and set its execute bits (chmod a+x your_script). Then, you can
launch the C code as a shell or perl script :-) The command line
arguments are put in 'argc' and 'argv' of the main functions, as in
ANSI C.

3) Examples

ex1.c: simplest example (hello world). Can also be launched directly
as a script: './ex1.c'.

ex2.c: more complicated example: find a number with the four
operations given a list of numbers (benchmark).

ex3.c: compute fibonacci numbers (benchmark).

ex4.c: more complicated: X11 program. Very complicated test in fact
because standard headers are being used ! As for ex1.c, can also be launched
directly as a script: './ex4.c'.

ex5.c: 'hello world' with standard glibc headers.

tcc.c: TCC can of course compile itself. Used to check the code
generator.

tcctest.c: auto test for TCC which tests many subtle possible bugs. Used
when doing 'make test'.

4) Full Documentation

Please read tcc-doc.html to have all the features of TCC.

Additional information is available for the Windows port in tcc-win32.txt.

License:
-------

TCC is distributed under the GNU Lesser General Public License (see
COPYING file).

Fabrice Bellard.