While I debug with GDB I can print string:
x/s $r0
The output is
IDog123456
I want to change the value so when I print x/s $r0 I will see
ICat45555
I have tried to :
set $r0+1 ={int} 0x43617434 #Cat4
set $r0+5 ={int} 0x35353535 #5555
But it doesn't work , How can I do that without malloc ? only with hex string please?
Generally, the gdb expression parser operates similar to the current language, so, in the above, when you write:
set $r0+1 ={int} 0x43617434 #Cat4
The left hand side is an integer constant, which can't be assigned to.
Instead, you should write this as you would in C:
set *($r0+1) = (int) 0x43617434
Which should do the job.
Sometime, you might end up needing to case the pointer of the LHS too, like this:
set *((int *) ($r0+1)) = (int) 0x43617434
But I suspect in your case you'll be OK.