[cx-oracle-users] segmentation violations

[Fred Y. <fc...@im...>]

Last week I started getting segmentation-violation crashes from cx_Oracle after using it without problems for years. I cannot figure out what changed and broke things. I hope you all can help me fix it. 

I'm testing with a fresh installation of cx_Oracle with the latest Oracle client libs that I could find: 

OS: RHEL 6.8 

Python: 2.7.8, built from source. 

cx_Oracle: 5.2.1 

Oracle instantclient libs: 12.1.0.2.0 


What I'm seeing now via a simple test driver is that the first call to cx_Oracle.connect() works. I'm able to get a cursor, execute the query, and get the results. But when I call connect() a second time I get a SIGSEGV. When I run the test driver different times I get slightly different errors. 



ORA-24550: signal received: [si_signo=11] [si_errno=0] [si_code=1] [si_int=0] [si_ptr=(nil)] [si_addr=0x870000] 
*** glibc detected *** python: free(): invalid pointer: 0x000000000073c150 *** 




Or 




ORA-24550: signal received: [si_signo=11] [si_errno=0] [si_code=1] [si_int=0] [si_ptr=(nil)] [si_addr=0x354] 
*** glibc detected *** python: double free or corruption (out): 0x00000000006f5f40 *** 




When I enable faulthandler I get a short trace in my test driver python code that just shows it failing in the connect() call. 




When I load the core file into gdb I get only a short backtrace, possibly because debug info is missing from some critical libs: 




#0 0x0000003c9ee0f6ab in raise () from /lib64/libpthread.so.0 
#1 <signal handler called> 
#2 0x00007f4122578e3f in __intel_ssse3_rep_memcpy () from /usr/lib/oracle/12.1/client64/lib/libclntsh.so.12.1 
#3 0x00007f4122571cc6 in _intel_fast_memcpy.P () from /usr/lib/oracle/12.1/client64/lib/libclntsh.so.12.1 
#4 0x00007f4121b113f6 in nsc2addr () from /usr/lib/oracle/12.1/client64/lib/libclntsh.so.12.1 
#5 0x0000000000000000 in ?? () 







Any suggestions on what I should do to fix this? 



-- 
Fred Yankowski 
fc...@im... +1-630-907-5019