diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2024-04-01 15:15:03 -0400 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2024-04-01 15:15:03 -0400 |
| commit | 14e4e8f8c66b2d4316ecb1276e688d67c25659c2 (patch) | |
| tree | ad20c2c3182ee1924b4388e3001a6051914a95a5 | |
| parent | ca4c60e05f81c57b4d72da867173fc524c76aa71 (diff) | |
| download | postgresql-14e4e8f8c66b2d4316ecb1276e688d67c25659c2.tar.gz postgresql-14e4e8f8c66b2d4316ecb1276e688d67c25659c2.zip | |
Avoid possible longjmp-induced logic error in PLy_trigger_build_args.
The "pltargs" variable wasn't marked volatile, which makes it unsafe
to change its value within the PG_TRY block. It looks like the worst
outcome would be to fail to release a refcount on Py_None during an
(improbable) error exit, which would likely go unnoticed in the field.
Still, it's a bug. A one-liner fix could be to mark pltargs volatile,
but on the whole it seems cleaner to arrange things so that we don't
change its value within PG_TRY.
Per report from Xing Guo. This has been there for quite awhile,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/CACpMh+DLrk=fDv07MNpBT4J413fDAm+gmMXgi8cjPONE+jvzuw@mail.gmail.com
| -rw-r--r-- | src/pl/plpython/plpy_exec.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/src/pl/plpython/plpy_exec.c b/src/pl/plpython/plpy_exec.c index e06fde1dd90..3145c696996 100644 --- a/src/pl/plpython/plpy_exec.c +++ b/src/pl/plpython/plpy_exec.c @@ -689,7 +689,7 @@ PLy_trigger_build_args(FunctionCallInfo fcinfo, PLyProcedure *proc, HeapTuple *r *pltrelid, *plttablename, *plttableschema, - *pltargs = NULL, + *pltargs, *pytnew, *pytold, *pltdata; @@ -713,6 +713,11 @@ PLy_trigger_build_args(FunctionCallInfo fcinfo, PLyProcedure *proc, HeapTuple *r return NULL; } } + else + { + Py_INCREF(Py_None); + pltargs = Py_None; + } PG_TRY(); { @@ -856,7 +861,7 @@ PLy_trigger_build_args(FunctionCallInfo fcinfo, PLyProcedure *proc, HeapTuple *r PyObject *pltarg; /* pltargs should have been allocated before the PG_TRY block. */ - Assert(pltargs); + Assert(pltargs && pltargs != Py_None); for (i = 0; i < tdata->tg_trigger->tgnargs; i++) { @@ -870,8 +875,7 @@ PLy_trigger_build_args(FunctionCallInfo fcinfo, PLyProcedure *proc, HeapTuple *r } else { - Py_INCREF(Py_None); - pltargs = Py_None; + Assert(pltargs == Py_None); } PyDict_SetItemString(pltdata, "args", pltargs); Py_DECREF(pltargs); |