Thread: BUG #13579: Server crashes after executing plpythonu function

The following bug has been logged on the website:

Bug reference:      13579
Logged by:          Paweł Michalak
Email address:      ppmichalakk@gmail.com
PostgreSQL version: 9.4.4
Operating system:   Debian 4.6.3-14
Description:

[pmichalak@asdasd ~] $ psql
psql (9.4.4)
Type "help" for help.
pmichalak=# create function a() returns setof record as $$
 return { 'a': 2, 'b': 3 }
$$ language plpythonu;
CREATE FUNCTION
pmichalak=# select * from a() as (b integer, c integer);
ERROR:  input of anonymous composite types is not implemented
CONTEXT:  while creating return value
PL/Python function "a"
pmichalak=# select * from a() as (b integer, c integer);
server closed the connection unexpectedly
        This probably means the server terminated abnormally
        before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.

Server log:
STATEMENT:  select * from a() as (b integer, c integer);
ERROR:  syntax error at or near "," at character 30
STATEMENT:  select * from q() as (b integer, c integer);
LOG:  server process (PID 14767) was terminated by signal 11: Segmentation
fault
DETAIL:  Failed process was running: select * from a() as (b integer, c
integer);
LOG:  terminating any other active server processes

ppmichalakk@gmail.com writes:
> pmichalak=# create function a() returns setof record as $$
>  return { 'a': 2, 'b': 3 }
> $$ language plpythonu;
> CREATE FUNCTION
> pmichalak=# select * from a() as (b integer, c integer);
> ERROR:  input of anonymous composite types is not implemented
> CONTEXT:  while creating return value
> PL/Python function "a"
> pmichalak=# select * from a() as (b integer, c integer);
> server closed the connection unexpectedly
>         This probably means the server terminated abnormally
>         before or while processing the request.
> The connection to the server was lost. Attempting reset: Failed.

Hm.  Looks like we're trying to free already-freed memory here:

#2  0x00000000007babc9 in ExceptionalCondition (
    conditionName=<value optimized out>, errorType=<value optimized out>,
    fileName=<value optimized out>, lineNumber=<value optimized out>)
    at assert.c:54
#3  0x00000000007dc292 in pfree (pointer=<value optimized out>) at mcxt.c:920
#4  0x00007fbde21a971f in PLy_free (ptr=<value optimized out>)
    at plpy_util.c:53
#5  0x00007fbde21a7ad4 in PLy_output_tuple_funcs (arg=0x2cd2a68,
    desc=0x2cdb240) at plpy_typeio.c:208
#6  0x00007fbde21a8b72 in PLy_output_record_funcs (arg=0x2cd2a68,
    desc=0x2cdb240) at plpy_typeio.c:277
#7  0x00007fbde21a25df in PLy_function_build_args (fcinfo=0x7ffd7f54aa10,
    proc=0x2cd2a48) at plpy_exec.c:419
#8  0x00007fbde21a279e in PLy_exec_function (fcinfo=0x7ffd7f54aa10,
    proc=0x2cd2a48) at plpy_exec.c:60
#9  0x00007fbde21a3351 in plpython_call_handler (fcinfo=0x7ffd7f54aa10)
    at plpy_main.c:232
#10 0x00000000005d96bb in ExecMakeTableFunctionResult (funcexpr=0x2cdaa28,
    econtext=0x2cda5b8, argContext=<value optimized out>,
    expectedDesc=0x2cdb240, randomAccess=0 '\000') at execQual.c:2189

Thanks for the report!

            regards, tom lane

ppmichalakk@gmail.com writes:
> pmichalak=# create function a() returns setof record as $$
>  return { 'a': 2, 'b': 3 }
> $$ language plpythonu;
> CREATE FUNCTION
> pmichalak=# select * from a() as (b integer, c integer);
> ERROR:  input of anonymous composite types is not implemented
> CONTEXT:  while creating return value
> PL/Python function "a"
> pmichalak=# select * from a() as (b integer, c integer);
> server closed the connection unexpectedly
>         This probably means the server terminated abnormally
>         before or while processing the request.
> The connection to the server was lost. Attempting reset: Failed.

Fixed, thanks for the report!

            regards, tom lane