Distinguish between a local pdb unlock and the tty unlock in root

ctx_debugger_from_hardening
Tyler Goodlet 2021-06-27 11:59:21 -04:00
parent 1ec1743c48
commit b603904d3e
1 changed files with 28 additions and 16 deletions

View File

@ -45,7 +45,8 @@ _global_actor_in_debug: Optional[Tuple[str, str]] = None
# lock in root actor preventing multi-access to local tty # lock in root actor preventing multi-access to local tty
_debug_lock: trio.StrictFIFOLock = trio.StrictFIFOLock() _debug_lock: trio.StrictFIFOLock = trio.StrictFIFOLock()
_pdb_complete: Optional[trio.Event] = None _local_pdb_complete: Optional[trio.Event] = None
_no_remote_has_tty: Optional[trio.Event] = None
# XXX: set by the current task waiting on the root tty lock # XXX: set by the current task waiting on the root tty lock
# and must be cancelled if this actor is cancelled via message # and must be cancelled if this actor is cancelled via message
@ -130,14 +131,15 @@ async def _acquire_debug_lock(uid: Tuple[str, str]) -> AsyncIterator[None]:
task_name = trio.lowlevel.current_task().name task_name = trio.lowlevel.current_task().name
log.debug( log.pdb(
f"Attempting to acquire TTY lock, remote task: {task_name}:{uid}") f"Attempting to acquire TTY lock, remote task: {task_name}:{uid}"
)
async with _debug_lock: async with _debug_lock:
# _debug_lock._uid = uid
_global_actor_in_debug = uid _global_actor_in_debug = uid
log.debug(f"TTY lock acquired, remote task: {task_name}:{uid}") log.debug(f"TTY lock acquired, remote task: {task_name}:{uid}")
yield yield
_global_actor_in_debug = None _global_actor_in_debug = None
@ -162,8 +164,17 @@ async def _hijack_stdin_relay_to_child(
subactor_uid: Tuple[str, str] subactor_uid: Tuple[str, str]
) -> str: ) -> str:
'''Hijack the tty in the root process of an actor tree such that
the pdbpp debugger console can be allocated to a sub-actor for repl
bossing.
global _pdb_complete '''
global _no_remote_has_tty
# mark the tty lock as being in use so that the runtime
# can try to avoid clobbering any connection from a child
# that's currently relying on it.
_no_remote_has_tty = trio.Event()
task_name = trio.lowlevel.current_task().name task_name = trio.lowlevel.current_task().name
@ -184,7 +195,7 @@ async def _hijack_stdin_relay_to_child(
# indicate to child that we've locked stdio # indicate to child that we've locked stdio
await ctx.started('Locked') await ctx.started('Locked')
log.runtime( # type: ignore log.pdb( # type: ignore
f"Actor {subactor_uid} ACQUIRED stdin hijack lock") f"Actor {subactor_uid} ACQUIRED stdin hijack lock")
# wait for unlock pdb by child # wait for unlock pdb by child
@ -204,6 +215,7 @@ async def _hijack_stdin_relay_to_child(
f"TTY lock released, remote task: {task_name}:{subactor_uid}") f"TTY lock released, remote task: {task_name}:{subactor_uid}")
log.debug(f"Actor {subactor_uid} RELEASED stdin hijack lock") log.debug(f"Actor {subactor_uid} RELEASED stdin hijack lock")
_no_remote_has_tty.set()
return "pdb_unlock_complete" return "pdb_unlock_complete"
@ -228,7 +240,7 @@ async def _breakpoint(
actor = tractor.current_actor() actor = tractor.current_actor()
task_name = trio.lowlevel.current_task().name task_name = trio.lowlevel.current_task().name
global _pdb_complete, _pdb_release_hook global _local_pdb_complete, _pdb_release_hook
global _local_task_in_debug, _global_actor_in_debug global _local_task_in_debug, _global_actor_in_debug
async def wait_for_parent_stdin_hijack( async def wait_for_parent_stdin_hijack(
@ -260,7 +272,7 @@ async def _breakpoint(
# TODO: shielding currently can cause hangs... # TODO: shielding currently can cause hangs...
# with trio.CancelScope(shield=True): # with trio.CancelScope(shield=True):
await _pdb_complete.wait() await _local_pdb_complete.wait()
await stream.send('pdb_unlock') await stream.send('pdb_unlock')
# sync with callee termination # sync with callee termination
@ -275,8 +287,8 @@ async def _breakpoint(
_local_task_in_debug = None _local_task_in_debug = None
log.debug(f"Child {actor} released parent stdio lock") log.debug(f"Child {actor} released parent stdio lock")
if not _pdb_complete or _pdb_complete.is_set(): if not _local_pdb_complete or _local_pdb_complete.is_set():
_pdb_complete = trio.Event() _local_pdb_complete = trio.Event()
# TODO: need a more robust check for the "root" actor # TODO: need a more robust check for the "root" actor
if actor._parent_chan and not is_root_process(): if actor._parent_chan and not is_root_process():
@ -291,7 +303,7 @@ async def _breakpoint(
# support for recursive entries to `tractor.breakpoint()` # support for recursive entries to `tractor.breakpoint()`
log.warning(f"{actor.uid} already has a debug lock, waiting...") log.warning(f"{actor.uid} already has a debug lock, waiting...")
await _pdb_complete.wait() await _local_pdb_complete.wait()
await trio.sleep(0.1) await trio.sleep(0.1)
# mark local actor as "in debug mode" to avoid recurrent # mark local actor as "in debug mode" to avoid recurrent
@ -299,7 +311,7 @@ async def _breakpoint(
_local_task_in_debug = task_name _local_task_in_debug = task_name
# assign unlock callback for debugger teardown hooks # assign unlock callback for debugger teardown hooks
_pdb_release_hook = _pdb_complete.set _pdb_release_hook = _local_pdb_complete.set
# this **must** be awaited by the caller and is done using the # this **must** be awaited by the caller and is done using the
# root nursery so that the debugger can continue to run without # root nursery so that the debugger can continue to run without
@ -328,13 +340,13 @@ async def _breakpoint(
# the lock must be released on pdb completion # the lock must be released on pdb completion
def teardown(): def teardown():
global _pdb_complete, _debug_lock global _local_pdb_complete, _debug_lock
global _global_actor_in_debug, _local_task_in_debug global _global_actor_in_debug, _local_task_in_debug
_debug_lock.release() _debug_lock.release()
_global_actor_in_debug = None _global_actor_in_debug = None
_local_task_in_debug = None _local_task_in_debug = None
_pdb_complete.set() _local_pdb_complete.set()
_pdb_release_hook = teardown _pdb_release_hook = teardown
@ -362,7 +374,7 @@ def _set_trace(actor=None):
pdb = _mk_pdb() pdb = _mk_pdb()
if actor is not None: if actor is not None:
log.runtime(f"\nAttaching pdb to actor: {actor.uid}\n") # type: ignore log.pdb(f"\nAttaching pdb to actor: {actor.uid}\n") # type: ignore
pdb.set_trace( pdb.set_trace(
# start 2 levels up in user code # start 2 levels up in user code
@ -392,7 +404,7 @@ breakpoint = partial(
def _post_mortem(actor): def _post_mortem(actor):
log.runtime(f"\nAttaching to pdb in crashed actor: {actor.uid}\n") log.pdb(f"\nAttaching to pdb in crashed actor: {actor.uid}\n")
pdb = _mk_pdb() pdb = _mk_pdb()
# custom Pdb post-mortem entry # custom Pdb post-mortem entry