[BUG] Stack overflow

flat assembler
Message board for the users of flat assembler.

Index > Compiler Internals > [BUG] Stack overflow

Author

Thread

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 30 Aug 2009, 17:33

Compiling the following code twice (re-opening the source first), will produce a stack overflow situation (not stack buffer overflow):

Code:

format binary as 'asm' ; Self destructible source :D

repeat 1000000
  ; db "(" ; This will make FASMW crash
  db "-" ; This crash FASMW and command line fasm
end repeat

[edit]Command line version also silently crash when "-" is used. I've changed the code to test for that and commented the "(" test.[/edit]

Last edited by LocoDelAssembly on 30 Aug 2009, 18:38; edited 1 time in total

30 Aug 2009, 17:33

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 19876
Location: In your JS exploiting you and your system

revolution 30 Aug 2009, 17:45

fasm (command line version) is fine with that above code (I get 'error: out of stack space.')

At 100000000 I only get 'error: out of memory.'

At 1000 I get 'error: illegal instruction'

30 Aug 2009, 17:45

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 30 Aug 2009, 18:29

Quote:

fasm (command line version) is fine with that above code (I get 'error: out of stack space.')

Yep, I almost posted this on Compilers Internals but after verifying this I posted here. Smile

BTW, that is just minimal example, but actually the same will happen if a very long chain of "(" or "-" is found in any expression.

30 Aug 2009, 18:29

Borsuc

Joined: 29 Dec 2005
Posts: 2465
Location: Bucharest, Romania

Borsuc 01 Sep 2009, 18:30

Is this really a bug, or simply because of too deep recursion? Confused

01 Sep 2009, 18:30

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8268
Location: Kraków, Poland

Tomasz Grysztar 01 Sep 2009, 18:34

It is a bug, because fasm should display "out of stack space" error in all cases.

01 Sep 2009, 18:34

< Last Thread | Next Thread >

Forum Rules:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum