BRIN: be more strict about required support procs

With improperly defined operator classes, it's possible to get a
Postgres crash because we'd try to invoke a procedure that doesn't
exist.  This is because the code is being a bit too trusting that the
opclass is correctly defined.  Add some ereport(ERROR)s for cases where
mandatory support procedures are not defined, transforming the crashes
into errors.

The particular case that was reported is an incomplete opclass in
PostGIS.

Backpatch all the way down to 13.

Reported-by: Tobias Wendorff <[email protected]>
Diagnosed-by: David Rowley <[email protected]>
Reviewed-by: Tomas Vondra <[email protected]>
Discussion: https://postgr.es/m/fb6d9a35-6c8e-4869-af80-0a4944a793a4@tu-dortmund.de

diff --git a/src/backend/access/brin/brin_bloom.c b/src/backend/access/brin/brin_bloom.c
index 40e1f303a0a1ff4ebb46bf7e873ea048187106c3..d160fa7f08ff327c393da232b3cb0888c59ab756 100644 (file)
--- a/src/backend/access/brin/brin_bloom.c
+++ b/src/backend/access/brin/brin_bloom.c
@@ -438,7 +438,6 @@ typedef struct BloomOpaque
     * consistency. We may need additional procs in the future.
     */
    FmgrInfo    extra_procinfos[BLOOM_MAX_PROCNUMS];
-   bool        extra_proc_missing[BLOOM_MAX_PROCNUMS];
 } BloomOpaque;
 
 static FmgrInfo *bloom_get_procinfo(BrinDesc *bdesc, uint16 attno,
@@ -714,27 +713,19 @@ bloom_get_procinfo(BrinDesc *bdesc, uint16 attno, uint16 procnum)
     */
    opaque = (BloomOpaque *) bdesc->bd_info[attno - 1]->oi_opaque;
 
-   /*
-    * If we already searched for this proc and didn't find it, don't bother
-    * searching again.
-    */
-   if (opaque->extra_proc_missing[basenum])
-       return NULL;
-
    if (opaque->extra_procinfos[basenum].fn_oid == InvalidOid)
    {
        if (RegProcedureIsValid(index_getprocid(bdesc->bd_index, attno,
                                                procnum)))
-       {
            fmgr_info_copy(&opaque->extra_procinfos[basenum],
                           index_getprocinfo(bdesc->bd_index, attno, procnum),
                           bdesc->bd_context);
-       }
        else
-       {
-           opaque->extra_proc_missing[basenum] = true;
-           return NULL;
-       }
+           ereport(ERROR,
+                   errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+                   errmsg_internal("invalid opclass definition"),
+                   errdetail_internal("The operator class is missing support function %d for column %d.",
+                                      procnum, attno));
    }
 
    return &opaque->extra_procinfos[basenum];

diff --git a/src/backend/access/brin/brin_inclusion.c b/src/backend/access/brin/brin_inclusion.c
index ef2247347f912e31f2f2d1e15caa1f40d15816ab..b86ca5744a34881072b25a519da044c14f0eea7f 100644 (file)
--- a/src/backend/access/brin/brin_inclusion.c
+++ b/src/backend/access/brin/brin_inclusion.c
@@ -82,7 +82,7 @@ typedef struct InclusionOpaque
 } InclusionOpaque;
 
 static FmgrInfo *inclusion_get_procinfo(BrinDesc *bdesc, uint16 attno,
-                                       uint16 procnum);
+                                       uint16 procnum, bool missing_ok);
 static FmgrInfo *inclusion_get_strategy_procinfo(BrinDesc *bdesc, uint16 attno,
                                                 Oid subtype, uint16 strategynum);
 
@@ -179,7 +179,7 @@ brin_inclusion_add_value(PG_FUNCTION_ARGS)
     * new value for emptiness; if it returns true, we need to set the
     * "contains empty" flag in the element (unless already set).
     */
-   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_EMPTY);
+   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_EMPTY, true);
    if (finfo != NULL && DatumGetBool(FunctionCall1Coll(finfo, colloid, newval)))
    {
        if (!DatumGetBool(column->bv_values[INCLUSION_CONTAINS_EMPTY]))
@@ -195,7 +195,7 @@ brin_inclusion_add_value(PG_FUNCTION_ARGS)
        PG_RETURN_BOOL(true);
 
    /* Check if the new value is already contained. */
-   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_CONTAINS);
+   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_CONTAINS, true);
    if (finfo != NULL &&
        DatumGetBool(FunctionCall2Coll(finfo, colloid,
                                       column->bv_values[INCLUSION_UNION],
@@ -210,7 +210,7 @@ brin_inclusion_add_value(PG_FUNCTION_ARGS)
     * it's not going to be used any longer.  However, the BRIN framework
     * doesn't allow for the value not being present.  Improve someday.
     */
-   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_MERGEABLE);
+   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_MERGEABLE, true);
    if (finfo != NULL &&
        !DatumGetBool(FunctionCall2Coll(finfo, colloid,
                                        column->bv_values[INCLUSION_UNION],
@@ -221,8 +221,7 @@ brin_inclusion_add_value(PG_FUNCTION_ARGS)
    }
 
    /* Finally, merge the new value to the existing union. */
-   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_MERGE);
-   Assert(finfo != NULL);
+   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_MERGE, false);
    result = FunctionCall2Coll(finfo, colloid,
                               column->bv_values[INCLUSION_UNION], newval);
    if (!attr->attbyval &&
@@ -506,7 +505,7 @@ brin_inclusion_union(PG_FUNCTION_ARGS)
    }
 
    /* Check if A and B are mergeable; if not, mark A unmergeable. */
-   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_MERGEABLE);
+   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_MERGEABLE, true);
    if (finfo != NULL &&
        !DatumGetBool(FunctionCall2Coll(finfo, colloid,
                                        col_a->bv_values[INCLUSION_UNION],
@@ -517,8 +516,7 @@ brin_inclusion_union(PG_FUNCTION_ARGS)
    }
 
    /* Finally, merge B to A. */
-   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_MERGE);
-   Assert(finfo != NULL);
+   finfo = inclusion_get_procinfo(bdesc, attno, PROCNUM_MERGE, false);
    result = FunctionCall2Coll(finfo, colloid,
                               col_a->bv_values[INCLUSION_UNION],
                               col_b->bv_values[INCLUSION_UNION]);
@@ -539,10 +537,12 @@ brin_inclusion_union(PG_FUNCTION_ARGS)
  * Cache and return inclusion opclass support procedure
  *
  * Return the procedure corresponding to the given function support number
- * or null if it is not exists.
+ * or null if it is not exists.  If missing_ok is true and the procedure
+ * isn't set up for this opclass, return NULL instead of raising an error.
  */
 static FmgrInfo *
-inclusion_get_procinfo(BrinDesc *bdesc, uint16 attno, uint16 procnum)
+inclusion_get_procinfo(BrinDesc *bdesc, uint16 attno, uint16 procnum,
+                      bool missing_ok)
 {
    InclusionOpaque *opaque;
    uint16      basenum = procnum - PROCNUM_BASE;
@@ -564,13 +564,18 @@ inclusion_get_procinfo(BrinDesc *bdesc, uint16 attno, uint16 procnum)
    {
        if (RegProcedureIsValid(index_getprocid(bdesc->bd_index, attno,
                                                procnum)))
-       {
            fmgr_info_copy(&opaque->extra_procinfos[basenum],
                           index_getprocinfo(bdesc->bd_index, attno, procnum),
                           bdesc->bd_context);
-       }
        else
        {
+           if (!missing_ok)
+               ereport(ERROR,
+                       errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+                       errmsg_internal("invalid opclass definition"),
+                       errdetail_internal("The operator class is missing support function %d for column %d.",
+                                          procnum, attno));
+
            opaque->extra_proc_missing[basenum] = true;
            return NULL;
        }

diff --git a/src/backend/access/brin/brin_minmax_multi.c b/src/backend/access/brin/brin_minmax_multi.c
index 88214720bff123aae6f7c96bc244f00ca09ea63a..0d1507a2a36248e6ca427d81a180bb8916fafd34 100644 (file)
--- a/src/backend/access/brin/brin_minmax_multi.c
+++ b/src/backend/access/brin/brin_minmax_multi.c
@@ -111,7 +111,6 @@
 typedef struct MinmaxMultiOpaque
 {
    FmgrInfo    extra_procinfos[MINMAX_MAX_PROCNUMS];
-   bool        extra_proc_missing[MINMAX_MAX_PROCNUMS];
    Oid         cached_subtype;
    FmgrInfo    strategy_procinfos[BTMaxStrategyNumber];
 } MinmaxMultiOpaque;
@@ -2872,27 +2871,19 @@ minmax_multi_get_procinfo(BrinDesc *bdesc, uint16 attno, uint16 procnum)
     */
    opaque = (MinmaxMultiOpaque *) bdesc->bd_info[attno - 1]->oi_opaque;
 
-   /*
-    * If we already searched for this proc and didn't find it, don't bother
-    * searching again.
-    */
-   if (opaque->extra_proc_missing[basenum])
-       return NULL;
-
    if (opaque->extra_procinfos[basenum].fn_oid == InvalidOid)
    {
        if (RegProcedureIsValid(index_getprocid(bdesc->bd_index, attno,
                                                procnum)))
-       {
            fmgr_info_copy(&opaque->extra_procinfos[basenum],
                           index_getprocinfo(bdesc->bd_index, attno, procnum),
                           bdesc->bd_context);
-       }
        else
-       {
-           opaque->extra_proc_missing[basenum] = true;
-           return NULL;
-       }
+           ereport(ERROR,
+                   errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+                   errmsg_internal("invalid opclass definition"),
+                   errdetail_internal("The operator class is missing support function %d for column %d.",
+                                      procnum, attno));
    }
 
    return &opaque->extra_procinfos[basenum];