Closed
Description
Brief description
When a packet list field is provided with a default list for value, instances of the given packet then just .copy() the packet list without copying the packets inside.
Consequently, modifying anything in a packet of the list from an instance of the owner packet modifies the thing for other instances (except for clones!)
Scapy version
2.6.1
Python version
3.8.6
Operating system
Windows
Additional environment information
No response
How to reproduce
class B(Packet):
fields_desc = [
ByteField("value", default=0),
]
class A(Packet):
fields_desc = [
PacketListField("b", pkt_cls=B, default=[B(value=i) for i in range(3)])
]
a0 = A()
a1 = A()
a1_clone = a1.copy()
a2 = A()
a1.b[1].value = 10
a3 = A()
print("a0:")
a0.show()
print("a1:")
a1.show()
print("Clone of a1:")
a1_clone.show()
print("a2:")
a2.show()
print("a3:")
a3.show()Actual result
a0:
###[ A ]###
\b \
|###[ B ]###
| value = 0
|###[ B ]###
| value = 10
|###[ B ]###
| value = 2
a1:
###[ A ]###
\b \
|###[ B ]###
| value = 0
|###[ B ]###
| value = 10
|###[ B ]###
| value = 2
Clone of a1:
###[ A ]###
\b \
|###[ B ]###
| value = 0
|###[ B ]###
| value = 1
|###[ B ]###
| value = 2
a2:
###[ A ]###
\b \
|###[ B ]###
| value = 0
|###[ B ]###
| value = 10
|###[ B ]###
| value = 2
a3:
###[ A ]###
\b \
|###[ B ]###
| value = 0
|###[ B ]###
| value = 10
|###[ B ]###
| value = 2
Expected result
b[1].value should be 10 for a1 only.
Related resources
No response