def gendisk_name(gendisk: gdb.Value) -> str:
"""
Returns the name of the provided block device.
This method evaluates the block device and returns the name,
including partition number, if applicable.
Args:
gendisk: A ``struct gendisk`` or ``struct hd_struct`` for which to
return the name. The value must be of type ``struct gendisk``
or ``struct hd_struct``.
Returns:
:obj:`str`: The name of the block device
Raises:
:obj:`.InvalidArgumentError`: gendisk does not describe a
``struct gendisk`` or ``struct hd_struct``
"""
if gendisk.type.code == gdb.TYPE_CODE_PTR:
gendisk = gendisk.dereference()
if get_basic_type(gendisk.type) == types.gendisk_type:
return gendisk['disk_name'].string()
if get_basic_type(gendisk.type) == types.hd_struct_type:
parent = dev_to_gendisk(part_to_dev(gendisk)['parent'])
return "{}{:d}".format(gendisk_name(parent), int(gendisk['partno']))
raise InvalidArgumentError("expected {} or {}, not {}".format(
types.gendisk_type, types.hd_struct_type, gendisk.type.unqualified()))
def klist_for_each(klist: gdb.Value) -> Iterable[gdb.Value]:
"""
Iterate over a klist and yield each node
Args:
klist: The list to iterate. The value must be of type
``struct klist`` or ``struct klist *``.
Yields:
:obj:`gdb.Value`: The next node in the list. The value is of type
``struct klist_node``.
"""
if klist.type == types.klist_type.pointer():
klist = klist.dereference()
elif klist.type != types.klist_type:
raise InvalidArgumentError(
"klist must be gdb.Value representing 'struct klist' or 'struct klist *' not {}"
.format(klist.type))
if klist.type is not types.klist_type:
types.override('struct klist', klist.type)
for node in list_for_each_entry(klist['k_list'], types.klist_node_type,
'n_node'):
if node['n_klist'] != klist.address:
raise KlistCorruptedError("Corrupted")
yield node
def decode_uuid_t(value: gdb.Value) -> uuid.UUID:
"""
Decode a Linux kernel uuid_t into a Python-style UUID object
Args:
value (gdb.Value): The uuid_t to be decoded
Returns:
uuid.UUID: The UUID object that describes the value
Raises:
TypeError: value is not gdb.Value<uuid_t>
"""
if not isinstance(value, gdb.Value):
raise TypeError("value must be gdb.Value")
if value.type != types.uuid_t_type:
if (value.type.code == gdb.TYPE_CODE_PTR
and value.type.target() == types.uuid_t_type):
value = value.dereference()
else:
raise TypeError("value must describe a uuid_t")
if struct_has_member(types.uuid_t_type, 'b'):
member = 'b'
else:
member = '__u_bits'
return decode_uuid(value[member])
def make_node_iterator(node_ptr: gdb.Value):
""" """
# Yield nodes, from left to right
while node_ptr != 0:
node = node_ptr.dereference()
node_ptr = node['next']
yield node['data']
def _to_ast_ptr(value: gdb.Value) -> gdb.Value:
if value.type.code == gdb.TYPE_CODE_PTR:
if value.type.target().name == "ast_t":
return value
else:
return _to_ast_ptr(value.dereference())
elif value.type.code == gdb.TYPE_CODE_TYPEDEF and value.type.name == "ast_ptr_t":
return value
raise ValueError
def show_one_mount(self, mnt: gdb.Value, args: argparse.Namespace) -> None:
if mnt.type.code == gdb.TYPE_CODE_PTR:
mnt = mnt.dereference()
flags = ""
if args.f:
flags = " ({})".format(mount_flags(mnt))
path = d_path(mnt, mount_root(mnt))
if args.v:
print("{:016x} {:016x} {:<10} {:<16} {}"
.format(int(mnt.address), int(mount_super(mnt)),
mount_fstype(mnt), mount_device(mnt), path))
else:
print("{} on {} type {}{}"
.format(mount_device(mnt), path, mount_fstype(mnt), flags))
def list_for_each(list_head: gdb.Value,
include_head: bool = False,
reverse: bool = False,
print_broken_links: bool = True,
exact_cycles: bool = False) -> Iterator[gdb.Value]:
"""
Iterate over a list and yield each node
Args:
list_head: The list to iterate. The value must be of type
``struct list_head`` or ``struct list_head *``.
include_head (optional): Include the head of the list in
iteration - useful for lists with no anchors
reverse (optional): Iterate the list in reverse order
(follow the ``prev`` links)
print_broken_links (optional): Print warnings about broken links
exact_cycles (optional): Detect and raise an exception if
a cycle is detected in the list
Yields:
gdb.Value: The next node in the list. The value is
of type ``struct list_head``.
Raises:
:obj:`.CorruptListError`: the list is corrupted
:obj:`.ListCycleError`: the list contains cycles
:obj:`BufferError`: portions of the list cannot be read
:obj:`gdb.NotAvailableError`: The target value is not available.
"""
pending_exception = None
if not isinstance(list_head, gdb.Value):
raise ArgumentTypeError('list_head', list_head, gdb.Value)
if list_head.type == types.list_head_type.pointer():
list_head = list_head.dereference()
elif list_head.type != types.list_head_type:
raise UnexpectedGDBTypeError('list_head', list_head,
types.list_head_type)
if list_head.type is not types.list_head_type:
types.override('struct list_head', list_head.type)
fast = None
if int(list_head.address) == 0:
raise CorruptListError("list_head is NULL pointer.")
next_ = 'next'
prev_ = 'prev'
if reverse:
next_ = 'prev'
prev_ = 'next'
if exact_cycles:
visited: Set[int] = set()
if include_head:
yield list_head
try:
nxt = list_head[next_]
prev = list_head
if int(nxt) == 0:
raise CorruptListError("{} pointer is NULL".format(next_))
node = nxt.dereference()
except gdb.error as e:
raise BufferError("Failed to read list_head {:#x}: {}".format(
int(list_head.address), str(e))) from e
last_good_addr = None
while node.address != list_head.address:
if exact_cycles:
if int(node.address) in visited:
raise ListCycleError("Cycle in list detected.")
visited.add(int(node.address))
try:
if int(prev.address) != int(node[prev_]):
error = f"broken {prev_} link {int(prev.address):#x} "
error += f"-{next_}-> {int(node.address):#x} "
error += f"-{prev_}-> {int(node[prev_]):#x}"
pending_exception = CorruptListError(error)
if print_broken_links:
print(error)
# broken prev link means there might be a cycle that
# does not include the initial head, so start detecting
# cycles
if not exact_cycles and fast is None:
fast = node
nxt = node[next_]
# only yield after trying to read something from the node, no
# point in giving out bogus list elements
yield node
except gdb.error as e:
if last_good_addr is not None:
last_good_str = f"0x{last_good_addr:x}"
else:
last_good_str = "(none)"
raise BufferError(
f"Failed to read list_head 0x{int(node.address):x} "
f"in list 0x{int(list_head.address):x}, last good "
f"list_head {last_good_str}: {str(e)}") from e
try:
if fast is not None:
# are we detecting cycles? advance fast 2 times and compare
# each with our current node (Floyd's Tortoise and Hare
# algorithm)
for i in range(2): # pylint: disable=unused-variable
fast = fast[next_].dereference()
if int(node.address) == int(fast.address):
raise ListCycleError("Cycle in list detected.")
except gdb.error:
# we hit an unreadable element, so just stop detecting cycles
# and the slow iterator will hit it as well
fast = None
prev = node
if int(nxt) == 0:
raise CorruptListError("{} -> {} pointer is NULL".format(
node.address, next_))
last_good_addr = int(node.address)
node = nxt.dereference()
if pending_exception is not None:
# The pylint error seems to think we'll raise None here
raise pending_exception # pylint: disable=raising-bad-type