Flag: Tornado! Hurricane!

 Forums >>  Debuggers  >>  PyDBG, threads that don't like to be single stepped?

Topic created on: February 22, 2012 21:39 CST by nomnom .

Hey everyone, I've got a question about using PyDBG. I'm trying to debug the latest VLC, and everything works just fine if I do a simple thing like :

dbg = pydbg()
dbg.load("vlc.exe")
dbg.run()

Now, the problem is if I set new threads to single_step(True), the program will basically hang at a certain point. And it's not at the first thread or anything, it's later in the program, roughly 5 threads in. The only change I make is :

def handle_new_thread(dbg):
    dbg.single_step(True)
    return DBG_CONTINUE

def handle_single_step(dbg):
    dbg.single_step(True)
    return DBG_CONTINUE

...

dbg.set_callback(EXCEPTION_SINGLE_STEP,     handle_single_step)
dbg.set_callback(CREATE_THREAD_DEBUG_EVENT, handle_new_thread)

And this will work on some programs, but on some (like VLC 2.0) in this instance, it will just hang at some point. The question is, any ideas why setting a thread to single step would cause an issue?

Thanks for the help, it's much appreciated.

No posts found under this topic.
Note: Registration is required to post to the forums.

There are 30,635 total registered users.


Recently Created Topics
Keep you Slim Easily
Apr/19
Your Best Slim &...
Apr/19
Amazing Your Lucky Skin
Apr/18
Your Skin Very Soft...
Apr/17
Question about debbu...
Apr/16
IDA PRO Struct Point...
Apr/15
problems with pseudo...
Apr/04
Problem with ollydbg
Mar/22
Should binaries be n...
Mar/22
Ida pro on infineon ...
Mar/10


Recent Forum Posts
Should binaries be n...
Kolisar
Problem with ollydbg
nullx42
!findtrampoline Immu...
skycrack
looking for a softwa...
raxen
Documenting reversed...
raxen
.orpc section what's...
mbin
Pydbg load() issue
phreak
Pydbg load() issue
netw0rm
How would you interp...
mbin
Pydbg load() issue
phreak


Recent Blog Entries
loisjoneis
Apr/19
Detox Max Review - amazing ...

martanhawkings
Apr/19
iPhone 4S- Purchase Apple’s...

elenablacik
Apr/18
Cleanse Pure Premium Supple...

hermesfrsac
Apr/17
Il convient que vous devrie...

oleavr
Apr/17
frida.re 1.2.0 is out, with...

More ...


Recent Blog Comments
pedram on:
Dec/21
frida.github.io: scriptable...

cin100dy on:
Dec/16
Devil May Cry Cosplay Costu...

NeOXQuiCk on:
Nov/26
DONGLE

maharlee on:
Nov/21
Cheap Nike Shoes NZ,Nike Sh...

capadleman on:
Jun/19
Using NtCreateThreadEx for ...

More ...


Imagery
SoySauce Blueprint
Jun 6, 2008

[+] expand

View Gallery (11) / Submit