Memory Leak Fixes

[L1l1thLY]

I found a few memory leaks in the code and attempted to fix them. Could you please take a look and confirm whether the fixes are correct? I’m not entirely sure, but the changes are as follows:

1. Line 2537-2538 (vec_eachFilter): pzErrMsg allocated but not freed on error
2. Line 1651-1652 (vec_slice): Early return without calling cleanup(vector)
3. Line 1674-1675 (vec_slice): Early return without calling cleanup(vector)
4. Line 5145-5152 (vec0_init): zSql not freed before goto error
5. Line 7064 (vec0Filter_knn): knn_data not freed on cleanup when error occurs
6. Line 8276-8278 (vec0Update_Insert): zSql not freed before goto cleanup
7. Lines 9409-9468 (vec_static_blob_entriesFilter): Multiple memory leaks - err, knn_data, queryVector, topk_rowids, distances, candidates, taken not properly freed on errors

[L1l1thLY]

8. vec0_free function (lines 3601-3638)

Issue: The function did not free partition column names, auxiliary column names, metadata column names, and metadata chunk shadow table names.

Fix: Added three loops to free this memory:

• paritition_columns[i].name - partition column names
• auxiliary_columns[i].name - auxiliary column names
• shadowMetadataChunksNames[i] - metadata chunk shadow table names
• metadata_columns[i].name - metadata column names

9. vec0_init error handling (lines 5180-5182)

Issue: In the error path, only vec0_free(pNew) was called to free member variables, but the pNew structure itself was not freed.

Fix: Added sqlite3_free(pNew) after vec0_free(pNew).

10. vec0Update_UpdateAuxColumn function (line 8666)

Issue: zSql allocated via sqlite3_mprintf was never freed.

Fix: Added sqlite3_free((void *)zSql) immediately after the sqlite3_prepare_v2 call.

11. vec0_write_metadata_value function (lines 8108 and 8130)

Issue: zSql was not freed in two places:

• SQL statement for UPDATE or INSERT operations
• SQL statement for DELETE operations

Fix: Added sqlite3_free((void *)zSql) after each sqlite3_prepare_v2 call.

12. vec0Update_Delete_ClearMetadata function (lines 8572 and 8580)

Issue:

• zSql was not freed when sqlite3_prepare_v2 failed
• stmt was not finalized when sqlite3_step failed

Fix:

• Added sqlite3_free((void *)zSql) after the sqlite3_prepare_v2 call
• Added sqlite3_finalize(stmt) in the error path