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 cc274256b31c94b64a8e3e1582116d57fd5c646a..48027da0225269d01c699e4d2dde8d639111dfe6 100644 (file)
--- a/src/backend/access/brin/brin_bloom.c
+++ b/src/backend/access/brin/brin_bloom.c
@@ -412,7 +412,6 @@ 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,
@@ -685,27 +684,19 @@ 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 0b384c0bd1eff1220c06b712f45f2a2e1191512f..39f11e949be88f7dbddff86877ed013a2077d625 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 16c7c41a3276590434731c065e5f4cf7bbc5cdcf..21d188b654b537d05a33897c4450ffc346d2f070 100644 (file)
--- a/src/backend/access/brin/brin_minmax_multi.c
+++ b/src/backend/access/brin/brin_minmax_multi.c
@@ -112,7 +112,6 @@
 typedef struct MinmaxMultiOpaque
 {
    FmgrInfo    extra_procinfos[MINMAX_MAX_PROCNUMS];
-   bool        extra_proc_missing[MINMAX_MAX_PROCNUMS];
    Oid         cached_subtype;
    FmgrInfo    strategy_procinfos[BTMaxStrategyNumber];
 } MinmaxMultiOpaque;
@@ -2864,27 +2863,19 @@ 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];