logs archiveIRC Archive / Undernet / #asm / 2007 / January / 29 / 1
bor0
hey, dbtid :)
here is something funny to check - http://www.youtube.com/watch?v=M4KX7SkDe4Q
dbtid
hi
jox
for the instruction cmpl $0x0008, 0xfffffff0(%ebp)
would 0xfffffff0(%ebp) be a stack variable?
edcba
maybe maybe not
depends on the value of ebp and esp :)
but usually it is
jox
thanks just experimenting
is there a way of getting GDB to examine whats at 0xfffffff0(%ebp) ?
like if i break at that instruction
i r $ebp gives 0xbfc0d728
edcba
don't there is a x command ?
like x -0x10(%ebp)
jox
x/x fffffff0($ebp) gives a segfault as memory is out of bounds
i guess what i need to find out is how the offset of fffffff0 works....
edcba
of course if the pointer is not valid
gdb won't show you memory
just display all registers
jox
when i break at that instruction %ebp is set to 0xbfc0d728
         

edcba
and you'll see if pointer is invalid
it doesn't look like so bad
jox
if you see my reverse enginering attempt its line 14, which executes fine but at debug time i can peel at the address 0xfffffff0(%ebp)
http://rafb.net/p/MKmXIO79.html
cant peek*
t1t0
anyone available ?
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