Обсуждение: BUG #17416: Server crashes due to python3 stack overflow on executing multiple plpy.rollback() calls
BUG #17416: Server crashes due to python3 stack overflow on executing multiple plpy.rollback() calls
От
PG Bug reporting form
Дата:
The following bug has been logged on the website:
Bug reference: 17416
Logged by: Alexander Lakhin
Email address: exclusion@gmail.com
PostgreSQL version: 14.2
Operating system: Ubuntu 20.04
Description:
When executing the following script:
psql -c "
CREATE EXTENSION plpython3u;
CREATE FUNCTION plpy_xact_test() RETURNS int
LANGUAGE plpython3u
AS '
plpy.rollback()
return 1
'"
for i in `seq 500`; do echo "SELECT plpy_xact_test();"; done | psql
I get the server crash with the following stack trace:
Core was generated by `postgres: law regression [local] SELECT
'.
Program terminated with signal SIGABRT, Aborted.
#0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
50 ../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#1 0x00007f27fc652859 in __GI_abort () at abort.c:79
#2 0x00007f27f2987c38 in ?? () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#3 0x00007f27f2aa56a9 in Py_FatalError () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#4 0x00007f27f2ade3e7 in _Py_CheckRecursiveCall () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#5 0x00007f27f2b7237c in ?? () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#6 0x00007f27f2bbc9b6 in _PyObject_CallMethodId () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#7 0x00007f27f2aa5260 in ?? () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#8 0x00007f27f2aa555b in ?? () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#9 0x00007f27f2aa56a9 in Py_FatalError () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#10 0x00007f27f2ade3e7 in _Py_CheckRecursiveCall () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#11 0x00007f27f29884ec in _PyEval_EvalFrameDefault () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#12 0x00007f27f2addecb in _PyEval_EvalCodeWithName () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#13 0x00007f27f2ade252 in PyEval_EvalCodeEx () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#14 0x00007f27f2ade63f in PyEval_EvalCode () from
/usr/lib/x86_64-linux-gnu/libpython3.8.so.1.0
#15 0x00007f27f2ec0078 in PLy_procedure_call (proc=0x5616bf113c80,
kargs=0x7f27f2ecb79d "args", vargs=0x7f27f2808500)
at plpy_exec.c:1032
#16 0x00007f27f2ebd4aa in PLy_exec_function (fcinfo=0x5616bf110398,
proc=0x5616bf113c80) at plpy_exec.c:104
#17 0x00007f27f2ec0a11 in plpython3_call_handler (fcinfo=0x5616bf110398) at
plpy_main.c:270
#18 0x00005616bdb70449 in ExecInterpExpr (state=0x5616bf1102b0,
econtext=0x5616bf10ffb0, isnull=0x7ffdc73aea3f)
at execExprInterp.c:725
#19 0x00005616bdb728dc in ExecInterpExprStillValid (state=0x5616bf1102b0,
econtext=0x5616bf10ffb0,
isNull=0x7ffdc73aea3f) at execExprInterp.c:1824
#20 0x00005616bdbcdfb3 in ExecEvalExprSwitchContext (state=0x5616bf1102b0,
econtext=0x5616bf10ffb0,
isNull=0x7ffdc73aea3f) at ../../../src/include/executor/executor.h:339
#21 0x00005616bdbce02b in ExecProject (projInfo=0x5616bf1102a8) at
../../../src/include/executor/executor.h:373
#22 0x00005616bdbce275 in ExecResult (pstate=0x5616bf10fe98) at
nodeResult.c:136
#23 0x00005616bdb88cb0 in ExecProcNodeFirst (node=0x5616bf10fe98) at
execProcnode.c:463
#24 0x00005616bdb7c79c in ExecProcNode (node=0x5616bf10fe98) at
../../../src/include/executor/executor.h:257
#25 0x00005616bdb7f3ba in ExecutePlan (estate=0x5616bf10fc60,
planstate=0x5616bf10fe98, use_parallel_mode=false,
operation=CMD_SELECT, sendTuples=true, numberTuples=0,
direction=ForwardScanDirection, dest=0x5616bf0191d0,
execute_once=true) at execMain.c:1551
#26 0x00005616bdb7ced3 in standard_ExecutorRun (queryDesc=0x5616bef7da10,
direction=ForwardScanDirection, count=0,
execute_once=true) at execMain.c:361
#27 0x00005616bdb7ccbe in ExecutorRun (queryDesc=0x5616bef7da10,
direction=ForwardScanDirection, count=0,
execute_once=true) at execMain.c:305
#28 0x00005616bddfa2ec in PortalRunSelect (portal=0x5616befbf3e0,
forward=true, count=0, dest=0x5616bf0191d0)
at pquery.c:921
#29 0x00005616bddf9f10 in PortalRun (portal=0x5616befbf3e0,
count=9223372036854775807, isTopLevel=true, run_once=true,
dest=0x5616bf0191d0, altdest=0x5616bf0191d0, qc=0x7ffdc73aee40) at
pquery.c:765
#30 0x00005616bddf2e22 in exec_simple_query (query_string=0x5616bef5b980
"SELECT plpy_xact_test();") at postgres.c:1214
#31 0x00005616bddf7ce9 in PostgresMain (argc=1, argv=0x7ffdc73af060,
dbname=0x5616bef872c8 "regression",
username=0x5616bef872a8 "law") at postgres.c:4496
#32 0x00005616bdd1c4d3 in BackendRun (port=0x5616bef7cf00) at
postmaster.c:4530
#33 0x00005616bdd1bd2e in BackendStartup (port=0x5616bef7cf00) at
postmaster.c:4252
#34 0x00005616bdd17b23 in ServerLoop () at postmaster.c:1745
#35 0x00005616bdd17280 in PostmasterMain (argc=3, argv=0x5616bef559b0) at
postmaster.c:1417
#36 0x00005616bdc06738 in main (argc=3, argv=0x5616bef559b0) at main.c:209
The server log contains:
..
2022-02-23 12:58:23.640 MSK [810462] ERROR: invalid transaction
termination
2022-02-23 12:58:23.640 MSK [810462] CONTEXT: PL/Python function
"plpy_xact_test"
2022-02-23 12:58:23.640 MSK [810462] STATEMENT: SELECT plpy_xact_test();
2022-02-23 12:58:23.641 MSK [810462] ERROR: invalid transaction
termination
...
2022-02-23 12:58:23.657 MSK [810462] STATEMENT: SELECT plpy_xact_test();
2022-02-23 12:58:23.657 MSK [810462] ERROR: RecursionError: maximum
recursion depth exceeded
2022-02-23 12:58:23.657 MSK [810462] CONTEXT: Traceback (most recent call
last):
PL/Python function "plpy_xact_test"
2022-02-23 12:58:23.657 MSK [810462] STATEMENT: SELECT plpy_xact_test();
2022-02-23 12:58:23.657 MSK [810462] ERROR: invalid transaction
termination
2022-02-23 12:58:23.657 MSK [810462] CONTEXT: PL/Python function
"plpy_xact_test"
2022-02-23 12:58:23.657 MSK [810462] STATEMENT: SELECT plpy_xact_test();
2022-02-23 12:58:23.657 MSK [810462] ERROR: invalid transaction
termination
2022-02-23 12:58:23.657 MSK [810462] CONTEXT: PL/Python function
"plpy_xact_test"
2022-02-23 12:58:23.657 MSK [810462] STATEMENT: SELECT plpy_xact_test();
...
2022-02-23 12:58:23.658 MSK [810462] ERROR: invalid transaction
termination
2022-02-23 12:58:23.658 MSK [810462] CONTEXT: PL/Python function
"plpy_xact_test"
2022-02-23 12:58:23.658 MSK [810462] STATEMENT: SELECT plpy_xact_test();
Fatal Python error: Cannot recover from stack overflow.
Python runtime state: initialized
Current thread 0x00007f27fc628740 (most recent call first):
File "<string>", line 3 in __plpython_procedure_plpy_xact_test_16390
File "<string>", line 1 in <module>
File "<string>", line 3 in __plpython_procedure_plpy_xact_test_16390
File "<string>", line 1 in <module>
File "<string>", line 3 in __plpython_procedure_plpy_xact_test_16390
...
File "<string>", line 1 in <module>
File "<string>", line 3 in __plpython_procedure_plpy_xact_test_16390
File "<string>", line 1 in <module>
...
2022-02-23 12:58:23.818 MSK [810446] LOG: server process (PID 810462) was
terminated by signal 6: Aborted
2022-02-23 12:58:23.818 MSK [810446] DETAIL: Failed process was running:
SELECT plpy_xact_test();
Reproduced on REL_11_0..master.
PG Bug reporting form <noreply@postgresql.org> writes:
> When executing the following script:
> psql -c "
> CREATE EXTENSION plpython3u;
> CREATE FUNCTION plpy_xact_test() RETURNS int
> LANGUAGE plpython3u
> AS '
> plpy.rollback()
> return 1
> '"
> for i in `seq 500`; do echo "SELECT plpy_xact_test();"; done | psql
> I get the server crash with the following stack trace:
Interesting. For me, 500 repetitions won't crash it, but 1000 will.
Apparently, each escape out of plpy.rollback leaves an open frame
on Python's internal control stack, and eventually it barfs.
So this is a different way to reach the problems already under
investigation at [1]. You don't really need a bleeding-edge
Python at all.
regards, tom lane
[1] https://www.postgresql.org/message-id/flat/3375ffd8-d71c-2565-e348-a597d6e739e3@enterprisedb.com