Re: Avoid possible dereference null pointer (src/backend/catalog/pg_depend.c)

Em qua., 22 de mai. de 2024 às 13:09, Ranier Vilela <ranier(dot)vf(at)gmail(dot)com>
escreveu:

> Em qua., 22 de mai. de 2024 às 11:44, Ranier Vilela <ranier(dot)vf(at)gmail(dot)com>
> escreveu:
>
>> Hi.
>>
>> Per Coverity.
>>
>> 2. returned_null: SearchSysCacheAttName returns NULL (checked 20 out of
>> 21 times).
>> 3. var_assigned: Assigning: ptup = NULL return value from
>> SearchSysCacheAttName.
>> 964 ptup = SearchSysCacheAttName(relid, attname);
>> CID 1545986: (#1 of 1): Dereference null return value (NULL_RETURNS)
>> 4. dereference: Dereferencing ptup, which is known to be NULL.
>>
>> The functions SearchSysCacheAttNum and SearchSysCacheAttName,
>> need to have the result checked.
>>
>> The commit 5091995
>> <https://github.com/postgres/postgres/commit/509199587df73f06eda898ae13284292f4ae573a>,
>> left an oversight.
>>
>> Fixed by the patch attached, a change of style, unfortunately, was
>> necessary.
>>
> v1 Attached, fix wrong column variable name in error report.
>
1. Another concern is the function *get_partition_ancestors*,
which may return NIL, which may affect *llast_oid*, which does not handle
NIL entries.

2. Is checking *relispartition* enough?
There a function *check_rel_can_be_partition*
(src/backend/utils/adt/partitionfuncs.c),
which performs a much more robust check, would it be worth using it?

With the v2 attached, 1 is handled, but, in this case,
will it be the most correct?

best regards,
Ranier Vilela