Re: Assistance Required: Timeout or Buffer Overflow Issue in PostgreSQL Client Application

Hi,

Please find the complete stack trace, the language is C and thread here was
just performing the operation of fetching records from the postgresDB using
SQL_get_tpf_rw() function for which I've also attached implementation here
as well

Stack trace of thread 966070:

#0
0x00000000f7ee1129 __kernel_vsyscall (linux-gate.so.1)

#1
0x00000000f6ba23b7 __poll (libc.so.6)

#2
0x00000000f792e5b5 __interceptor_poll (libasan.so.8)

#3
0x00000000f72b30a8 pqSocketCheck (libpq.so.5)

#4
0x00000000f72b3864 pqWaitTimed (libpq.so.5)

#5
0x00000000f72b38d2 pqWait (libpq.so.5)

#6
0x00000000f72aff03 PQgetResult (libpq.so.5)

#7
0x00000000f72b036a PQexecFinish (libpq.so.5)

#8
0x0000000008106dd4 checkLOCK (server)

#9
0x000000000811d871 SQL_get_tpf_rw (server)

#10
0x0000000008180269 get_tpf_rw (server)

#11
0x0000000008189e47 FINDC (server)

#12
0x000000000818cd20 FINWC (server)

#13
0x00000000f2d03778 _segKIP8 (kip8.so)

#14
0x000000000816ad0e call_segment (server)

#15
0x000000000816ba0b ENTRC (server)

#16
0x00000000f2d096ee _segKIP5 (kip5.so)

#17
0x000000000816ad0e call_segment (server)

#18
0x000000000816ba0b ENTRC (server)

#19
0x00000000f2d1722d _segKIP4 (kip4.so)

#20
0x000000000816ad0e call_segment (server)

#21
0x000000000816ba0b ENTRC (server)

#22
0x00000000f2d1dee1 _segKIPB (kipb.so)

#23
0x000000000816ad0e call_segment (server)

#24
0x000000000816c454 ENTNC (server)

#25
0x00000000f2d2be54 _segKIP9 (kip9.so)

#26
0x000000000816ad0e call_segment (server)

#27
0x00000000081c264d call_appl_entry (server)

#28
0x000000000807f227 extest (server)

#29
0x000000000808923f handle_COMMS_TYPE_FUNCTIONAL_MESSAGE (server)

#30
0x000000000808d849 handle_comms_message (server)

#31
0x00000000f77d6e41 worker (libuv.so.1)

#32
0x00000000f78ff67a _ZL17asan_thread_startPv (libasan.so.8)

#33
0x00000000f6b170ad start_thread (libc.so.6)

#34
0x00000000f6bb1dea __clone (libc.so.6)
Regards,
Sasmit Utkarsh
+91-7674022625

On Thu, Oct 24, 2024 at 9:47 PM Igor Korot <ikorot01@gmail.com> wrote:

Show quoted text

Hi,
Is this a complete backtrace?
Can you post a complete backtrace? We need to see if there is a reference
to your application code?

What language is it written in?
What operation this thread was performing?

Thank you.

On Thu, Oct 24, 2024 at 11:12 AM Sasmit Utkarsh <utkarshsasmit@gmail.com>
wrote:

Dear PostgreSQL Community Team,

I hope this message finds you well. I am reaching out for assistance

with an issue encountered in our application, which communicates with
PostgreSQL using the libpq client library.

Issue Details:
We have observed a problem where one of the application's threads gets

stuck during a database operation. Below is a stack trace of the affected
thread:

Application Logs:
Oct 23 10:08:44.806235 cucmtpccu1 shc-server@2.service[966034]:

0966070{ef5f81a7-d35b-4604-953d-a35665e505b7.010000}KIP8-SQL_get_tpf_rw()-SQL
read data from File Address before lock fa(-1810606079) fa(94145801) fa2
htonl(22549652)

Oct 23 10:08:44.806235 cucmtpccu1 shc-server@2.service[966034]:

0966070{ef5f81a7-d35b-4604-953d-a35665e505b7.010000}KIP8-SQL_get_tpf_rw()
SelectDataCommand = CALL SQL_select_data_procedure($1, $2, NULL, NULL)
hold(0) fa(-1810606079)

Oct 23 10:08:44.807814 cucmtpccu1 shc-server@2.service[966034]: ***

buffer overflow detected ***: terminated

Stack Trace of Thread 966070:
#0 0x00000000f7ee1129 __kernel_vsyscall (linux-gate.so.1)
#1 0x00000000f6ba23b7 __poll (libc.so.6)
#2 0x00000000f792e5b5 __interceptor_poll (libasan.so.8)
#3 0x00000000f72b30a8 pqSocketCheck (libpq.so.5)
#4 0x00000000f72b3864 pqWaitTimed (libpq.so.5)
#5 0x00000000f72b38d2 pqWait (libpq.so.5)
#6 0x00000000f72aff03 PQgetResult (libpq.so.5)
#7 0x00000000f72b036a PQexecFinish (libpq.so.5)
#8 0x0000000008106dd4 checkLOCK (server)
#9 0x000000000811d871 SQL_get_tpf_rw (server)
...

The stack trace shows that the thread is stuck in a poll operation while

waiting for socket activity within the PostgreSQL client library (libpq).
We suspect this could be related to a network timeout or issue. However,
the application logs indicate a buffer overflow before the crash, which
raises questions about whether these are related.

Questions:
-Could the buffer overflow be causing the crash, and if so, how is it

related to the socket activity?

-Are there specific configurations or checks we should perform to

diagnose this issue further?

-Any suggestions for possible solutions to resolve this problem?

For additional context, I've verified that the specified record does

exist in the database, and I am also attaching the implementation details
for the checkLOCK function corresponding to the stack trace.

Please let me know if you need any more details

Your assistance with troubleshooting this would be highly appreciated.

Regards,
Sasmit Utkarsh
+91-7674022625