Buffer overflow on too many break-points #32
Description
If you set a break-point on the same address numerous times the python process crashes. This happens e.g. when you set a bp from a callback function:
addr_1 = 0x...
addr_2 = 0x...
def cb_1(): print('1')
def cb_2():
with vm.break_on_physical(addr_1, cb_1)
...
with vm.break_on_physical(addr_2, cb_2)
...
# guest is calling addr_2 and addr_1 fiercely
The solution is rather obvious - one must keep track of addresses that already have a bp set and prevent duplicate bps. However, I thought SIGSEGV is not intended behavior so I did a little investigation.
Long story short, the buffer in struct Worker gets overflown and the co_thread pointer gets malformed. A following call to co_switch is going to kill the python process.