Memory Leak in PcapLiveDeviceList

[Yangc6]

Bug description

Description

Build Tutorial-LiveTraffic example
Run with Valgrind:
sudo valgrind --leak-check=full --show-leak-kinds=all --track-origins=yes ./Tutorial-LiveTraffic。Memory leak detected during network device enumeration in the PcapLiveDeviceList 。

Environment

• PcapPlusPlus version: 24.09
• libpcap version: 1.10.5
• OS: Linux
• Compiler: GCC
• Analysis Tool: Valgrind 3.13.0

Call Stack

main()
-> PcapLiveDeviceList::PcapLiveDeviceList()
-> PcapLiveDeviceList::fetchAllLocalDevices()
-> pcpp::internal::getAllLocalPcapDevices()
-> pcap_findalldevs()


### PcapPlusPlus versions tested on

PcapPlusPlus master branch, Other (specify in the next question)

### Other PcapPlusPlus version (if applicable)

_No response_

### Operating systems tested on

Linux

### Other operation systems (if applicable)

_No response_

### Compiler version

gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0

### Packet capture backend (if applicable)

libpcap

[seladb]

@Dimi1010 can you take a look? You updated this code recently I believe...

[Yangc6]

@seladb I found that using pcpp::P capLiveDeviceList::getInstance() has memory leaks. I used the same environment to test Tutorial-LiveTraffic in v23.09, and some other examples that use pcpp::P capLiveDeviceList::getInstance() also have memory leaks. I'm not sure if it's an issue with libpcap or this library.

[seladb]

@seladb I found that using pcpp::P capLiveDeviceList::getInstance() has memory leaks. I used the same environment to test Tutorial-LiveTraffic in v23.09, and some other examples that use pcpp::P capLiveDeviceList::getInstance() also have memory leaks. I'm not sure if it's an issue with libpcap or this library.

@Yangc6 If the memory leak is inside pcap_findalldevs, then it's libpcap and there's not much we can do with it... Can you confirm it's in pcap_findalldevs?

[Yangc6]

@seladb

I tested the pcap_findalldevs and found it fine.

[Yangc6]

This is a screenshot of testing Tutorial-LiveTraffic in v23.09.

[Dimi1010]

I am not showing any leaks. :/

PcapPlusPlus Version: master branch head (ab755348711dfb94fa0780c5aa71a8e6e614d132)
OS: Ubuntu 22.04 under WSL2
Libpcap version: 1.10.1
Compiler: GCC
Analysis: Valgrind 3.18.1

~/.vs/PcapPlusPlus/out/build/linux/tutorials_bin/Debug$ sudo valgrind --leak-check=full --show-leak-kinds=all --track-origins=yes ./Tutorial-LiveTraffic
==2682== Memcheck, a memory error detector
==2682== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==2682== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==2682== Command: ./Tutorial-LiveTraffic
==2682==
Interface info:
   Interface name:        eth0
   Interface description:
   MAC address:           00:15:5d:68:69:28
   Default gateway:       172.28.160.1
   Interface MTU:         1500

Starting async capture...
Results:
Ethernet packet count: 0
IPv4 packet count:     0
IPv6 packet count:     0
TCP packet count:      0
UDP packet count:      0
DNS packet count:      0
HTTP packet count:     0
SSL packet count:      0

Starting capture with packet vector...
Results:
Ethernet packet count: 2
IPv4 packet count:     2
IPv6 packet count:     0
TCP packet count:      0
UDP packet count:      2
DNS packet count:      0
HTTP packet count:     0
SSL packet count:      0

Starting capture in blocking mode...
Results:
Ethernet packet count: 0
IPv4 packet count:     0
IPv6 packet count:     0
TCP packet count:      0
UDP packet count:      0
DNS packet count:      0
HTTP packet count:     0
SSL packet count:      0

Sending 2 packets one by one...
2 packets sent

Sending 2 packets...
2 packets sent

Starting packet capture with a filter in place...
Results:
Ethernet packet count: 0
IPv4 packet count:     0
IPv6 packet count:     0
TCP packet count:      0
==2682== HEAP SUMMARY:
==2682==     in use at exit: 0 bytes in 0 blocks
==2682==   total heap usage: 2,646 allocs, 2,646 frees, 375,878 bytes allocated
==2682==
==2682== All heap blocks were freed -- no leaks are possible
==2682==
==2682== For lists of detected and suppressed errors, rerun with: -s
==2682== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

[Dimi1010]

Same with v23.09.

PcapPlusPlus Version: v23.09
OS: Ubuntu 22.04 under WSL2
Libpcap version: 1.10.1
Compiler: GCC
Analysis: Valgrind 3.18.1

~/.vs/PcapPlusPlus/out/build/linux/tutorials_bin/Debug$ sudo valgrind --leak-check=full --show-leak-kinds=all --track-origins=yes ./Tutorial-LiveTraffic
==3475== Memcheck, a memory error detector
==3475== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==3475== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==3475== Command: ./Tutorial-LiveTraffic
==3475==
Interface info:
   Interface name:        eth0
   Interface description:
   MAC address:           00:15:5d:68:69:28
   Default gateway:       172.28.160.1
   Interface MTU:         1500

Starting async capture...
Results:
Ethernet packet count: 6
IPv4 packet count:     2
IPv6 packet count:     0
TCP packet count:      0
UDP packet count:      2
DNS packet count:      0
HTTP packet count:     0
SSL packet count:      0

Starting capture with packet vector...
Results:
Ethernet packet count: 0
IPv4 packet count:     0
IPv6 packet count:     0
TCP packet count:      0
UDP packet count:      0
DNS packet count:      0
HTTP packet count:     0
SSL packet count:      0

Starting capture in blocking mode...
Results:
Ethernet packet count: 0
IPv4 packet count:     0
IPv6 packet count:     0
TCP packet count:      0
UDP packet count:      0
DNS packet count:      0
HTTP packet count:     0
SSL packet count:      0

Sending 0 packets one by one...
0 packets sent

Sending 0 packets...
0 packets sent

Starting packet capture with a filter in place...
Results:
Ethernet packet count: 0
IPv4 packet count:     0
IPv6 packet count:     0
TCP packet count:      0
UDP packet count:      0
DNS packet count:      0
HTTP packet count:     0
SSL packet count:      0
==3475==
==3475== HEAP SUMMARY:
==3475==     in use at exit: 0 bytes in 0 blocks
==3475==   total heap usage: 2,648 allocs, 2,648 frees, 376,090 bytes allocated
==3475==
==3475== All heap blocks were freed -- no leaks are possible
==3475==
==3475== For lists of detected and suppressed errors, rerun with: -s
==3475== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

[Yangc6]

@Dimi1010

Thanks, this code I downloaded compiled out to have a memory leak. The latest version pulled with git is no problem.