diff options
author | Tom Lane <tgl@sss.pgh.pa.us> | 2024-05-07 18:15:00 -0400 |
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committer | Tom Lane <tgl@sss.pgh.pa.us> | 2024-05-07 18:15:00 -0400 |
commit | 90d39929a8900ba38a3ded503481867ca3182849 (patch) | |
tree | 19ed60472fba2298ce6dcf1ac7e59e34bf7bbfc2 /src/pl/plpython/plpy_procedure.h | |
parent | cf07a47dc0c3b16778291e62d730537b45da51ef (diff) |
Don't corrupt plpython's "TD" dictionary in a recursive trigger call.
If a plpython-language trigger caused another one to be invoked,
the "TD" dictionary created for the inner one would overwrite the
outer one's "TD" dictionary. This is more or less the same problem
that 1d2fe56e4 fixed for ordinary functions in plpython, so fix it
the same way, by saving and restoring "TD" during a recursive
invocation.
This fix makes an ABI-incompatible change in struct PLySavedArgs.
I'm not too worried about that because it seems highly unlikely that
any extension is messing with those structs. We could imagine doing
something weird to preserve nominal ABI compatibility in the back
branches, like keeping the saved TD object in an extra element of
namedargs[]. However, that would only be very nominal compatibility:
if anything *is* touching PLySavedArgs, it would likely do the wrong
thing due to not knowing about the additional value. So I judge it
not worth the ugliness to do something different there.
(I also changed struct PLyProcedure, but its added field fits
into formerly-padding space, so that should be safe.)
Per bug #18456 from Jacques Combrink. This bug is very ancient,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/3008982.1714853799@sss.pgh.pa.us
Diffstat (limited to 'src/pl/plpython/plpy_procedure.h')
-rw-r--r-- | src/pl/plpython/plpy_procedure.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/src/pl/plpython/plpy_procedure.h b/src/pl/plpython/plpy_procedure.h index 8968b5c92e5..5db854fc8bd 100644 --- a/src/pl/plpython/plpy_procedure.h +++ b/src/pl/plpython/plpy_procedure.h @@ -16,6 +16,7 @@ typedef struct PLySavedArgs { struct PLySavedArgs *next; /* linked-list pointer */ PyObject *args; /* "args" element of globals dict */ + PyObject *td; /* "TD" element of globals dict, if trigger */ int nargs; /* length of namedargs array */ PyObject *namedargs[FLEXIBLE_ARRAY_MEMBER]; /* named args */ } PLySavedArgs; @@ -32,6 +33,7 @@ typedef struct PLyProcedure bool fn_readonly; bool is_setof; /* true, if function returns result set */ bool is_procedure; + bool is_trigger; /* called as trigger? */ PLyObToDatum result; /* Function result output conversion info */ PLyDatumToOb result_in; /* For converting input tuples in a trigger */ char *src; /* textual procedure code, after mangling */ |