Re: [Qemu-devel] Modifying a program counter

[Peter Maydell]

On 31 March 2013 23:33, Ivan Jovanovic <address@hidden> wrote:
> I am a Computer science student which is new to QEMU, new to this list.
>
> For the student project that I am working on, which is system security
> related, I am executing a program in QEMU user mode emulation. To simulate a
> program control flow change, like it happens in a real attack, I would like
> to modify program counter and 'tell' QEMU to jump to a certain instruction
> and continue execution from there.

Ignoring the fact that the program counter doesn't just change
at random in a real attack, I suggest you use QEMU's gdb stub.
You can connect a debugger to the stub, and then either manually
or under the control of a script stop execution of the guest binary
at any point, change its PC register and resume.

-- PMM