1.8 KiB
Introduction and Prerequisites
ntopng can be built with the support for the LLVM leaks sanitizer (https://clang.llvm.org/docs/LeakSanitizer.html). On Ubuntu you can install it with
sudo apt-get install -y clang-10 clang-tools-10
Compilation
Then you need to compile ntopng as follows
cd ~/ntopng
./autogen.sh && ./configure --with-sanitizer
make
If you want to use nDPI with leak detection support you need to do
cd ~/nDPI
./configure --with-sanitizer
make
Running
In order to enable the leaks sanitizer, it is necessary to set the ASAN_OPTIONS=detect_leaks=1
environment variable, for example with:
sudo ASAN_OPTIONS=detect_leaks=1 LSAN_OPTIONS=verbosity=1 ./ntopng -i enp6s0f1 --dont-change-user
it is important to use --dont-change-user as otherwise the leak detection will fail with the following error
==32547==LeakSanitizer has encountered a fatal error.
==32547==HINT: For debugging, try setting environment variable LSAN_OPTIONS=verbosity=1:log_threads=1
==32547==HINT: LeakSanitizer does not work under ptrace (strace, gdb, etc)
Leak Analysis
In case there are some leaks detected, when killing (nicely) ntopng, a memore leak log (note tht no leaks no log is generated) is produced. The log contains lines as the one below specifying where the memory leak has been encountered:
Direct leak of 8 byte(s) in 1 object(s) allocated from:
#0 0x4a175d in malloc (/home/ntop/ntopng/ntopng+0x4a175d)
#1 0x7f0b3ef0438b in pcap_create_interface /home/ntop/PF_RING/userland/libpcap/./pcap-linux.c:493
#2 0x6220000041e3 (<unknown module>)
Notes
The leak detector also identifies invalid memory accesses. The performance impact of running the address sanitizer is about a 2x slowdown (https://clang.llvm.org/docs/AddressSanitizer.html).