Address Sanitizer issue is resolved at my end. I am providing the details how it was solved , may be helpful for others.
Address sanitizer doesn’t detect memory leaks in Ubuntu 14.04 LTS with gcc version 4.8.4 . I have found a patch to gcc for Address Sanitizer at https://gcc.gnu.org/ml/gcc-patches/2013-11/msg01874.html. I have found the code changes related to this patch in the official gcc 4.9.X release. When I upgraded to gcc 4.9, then address sanitizer started detecting memory leaks . One more observation is that Address sanitizer throws the memory leak log only when program exits , if it is running in a for ever loop then it doesn’t show the leak log. Regards Vamsi > On Nov 15, 2016, at 11:57 PM, Bryan Call <bc...@apache.org> wrote: > > Don’t know why Apple Mail didn’t send this. I noticed after restarting: > > By default you should see some leaks from CRYPTO_malloc even if you don’t > have TLS/SSL configured. I am running Fedora 24. > > [bcall@homer trafficserver]$ sudo /usr/local/bin/traffic_server > traffic_server: using root directory '/usr/local' > ^Ctraffic_server: Interrupt (Signal sent by the kernel 0 0) > > ================================================================= > ==9081==ERROR: LeakSanitizer: detected memory leaks > > Direct leak of 48 byte(s) in 1 object(s) allocated from: > #0 0x7f2a242f7e60 in malloc (/lib64/libasan.so.3+0xc6e60) > #1 0x7f2a231320b7 in CRYPTO_malloc (/lib64/libcrypto.so.10+0x6e0b7) > > Indirect leak of 120 byte(s) in 1 object(s) allocated from: > #0 0x7f2a242f7e60 in malloc (/lib64/libasan.so.3+0xc6e60) > #1 0x7f2a231320b7 in CRYPTO_malloc (/lib64/libcrypto.so.10+0x6e0b7) > > SUMMARY: AddressSanitizer: 168 byte(s) leaked in 2 allocation(s). > > -Bryan > > > > >> On Nov 10, 2016, at 2:22 PM, Vamsi Ambati <va...@neumob.com >> <mailto:va...@neumob.com>> wrote: >> >> Hi Sudheer, >> >> Thanks for the quick response. >> I tried with your suggested code snippet but Address sanitizer doesn’t >> detect the leak. >> I even tried with gdb by introducing break point at __asan_report_error. >> >> >> Vamsi >> >>> On Nov 10, 2016, at 1:58 PM, Sudheer Vinukonda <sudheervinuko...@yahoo.com >>> <mailto:sudheervinuko...@yahoo.com>> wrote: >>> >>> Not sure if the *leak* in your test code below is detectable..since your >>> program is exiting after allocating the memory (system should automatically >>> reclaim the memory on process exit). >>> >>> You may try to modify it to something more explicit like the below - >>> >>>> #include <stdlib.h> >>>> void dummy() { >>>> char *c = (char*) malloc(20); >>> c = (char*) malloc(100); >>>> } >>>> int main() { >>>> dummy(); >>>> while(1) {} >>>> } >>> >>> >>> >>> On Nov 10, 2016, at 1:43 PM, Vamsi Ambati <va...@neumob.com >>> <mailto:va...@neumob.com>> wrote: >>> >>>> >>>> I am trying to resolve a memory leak issue with ATS 7.0 version. >>>> We are using ATS from the CDN perspective and developed 3 plugins. >>>> DevOps complains that traffic_server process gradually consumes lot of >>>> memory and does release back which is a sign of memory leak. >>>> I tried with Valgrind but it didn’t work because of LUA and one of our ATS >>>> community member suggested to use Address Sanitizer. >>>> I followed exactly the steps mentioned Debugging Traffic Server using >>>> ASAN >>>> <https://cwiki.apache.org/confluence/download/attachments/56066455/summit_asan.pptx?version=1&modificationDate=1429916307000&api=v2>. >>>> >>>> I have build the traffic server with CXXFLAGS=-fno-omit-frame-pointer >>>> -fsanitize=address >>>> Verified that traffic_server is build with ASAN library by 'ldd >>>> bin/traffic_server’ >>>> Restarted the traffic server with 'service nm-trafficserver restart'. >>>> >>>> I have adopted three approaches to catch the memory leak >>>> >>>> Approach 1: >>>> Just running the traffic server(with -f option) and continuously sending >>>> HTTP requests using wrk (from another machine) by attaching >>>> to a gdb . >>>> ' gdb $(pidof traffic_server)’ >>>> break __asan_report_error. >>>> >>>> Issue: I didn’t hit this function from the memory leak perspective. >>>> >>>> Approach 2: >>>> I have run the traffic server with PROXY_AUTO_EXIT and sending the http >>>> requests >>>> PROXY_AUTO_EXIT=30 ASAN_OPTIONS=detect_leaks=1:verbosity=2 >>>> bin/traffic_server -f >>>> >>>> Issue: Tool didn’t complain any thing about the memory leak. >>>> >>>> >>>> Approach 3: >>>> I have created simple code explicitly introducing the memory leak >>>> >>>> #include <stdlib.h> >>>> void dummy() { >>>> malloc(20); >>>> } >>>> int main() { >>>> dummy(); >>>> return 0; >>>> } >>>> >>>> Compiled with g++ -fsanitize=address add.cpp >>>> Executed like ASAN_OPTIONS=detect_leaks=1 ./a.out >>>> >>>> Issue: Tool didn’t detect this memory leak. >>>> >>>> >>>> Production System Configuration: >>>> >>>> 16Gb Ram with 8 cores VM. >>>> gcc --version >>>> gcc (Ubuntu 4.8.4-2ubuntu1~14.04.3) 4.8.4 >>>> >>>> Did any one encounter this ASAN issue on Ubuntu 14.04 ? If so, how did >>>> they resolve it ? >>>> Any other suggestions how to narrow down the memory leak issue with ATS ? >>>> >>>> >>>> >>>> Regards >>>> Vamsi >>>> >>>> PS: I am new to the community and new to Apache traffic server open source >>>> module too. >>>> >>>> >>>> >>>> >> >
