Hello Konstantin Komarov,
This is a semi-automatic email about new static checker warnings.
The patch be71b5cba2e6: "fs/ntfs3: Add attrib operations" from Aug
13, 2021, leads to the following Smatch complaint:
fs/ntfs3/attrib.c:1678 attr_allocate_frame()
error: we previously assumed 'attr_b' could be null (see line 1591)
fs/ntfs3/attrib.c
1582 /* add new segment [next_svcn : evcn1 - next_svcn )*/
1583 if (!ni->attr_list.size) {
1584 err = ni_create_attr_list(ni);
1585 if (err)
1586 goto out;
1587 /* layout of records is changed */
1588 le_b = NULL;
1589 attr_b = ni_find_attr(ni, NULL, &le_b, ATTR_DATA, NULL,
1590 0, NULL, &mi_b);
1591 if (!attr_b) {
^^^^^^
Check for NULL
1592 err = -ENOENT;
1593 goto out;
1594 }
1595
1596 attr = attr_b;
1597 le = le_b;
1598 mi = mi_b;
1599 goto repack;
1600 }
1601 }
1602
1603 svcn = evcn1;
1604
1605 /* Estimate next attribute */
1606 attr = ni_find_attr(ni, attr, &le, ATTR_DATA, NULL, 0, &svcn, &mi);
1607
1608 if (attr) {
1609 CLST alloc = bytes_to_cluster(
1610 sbi, le64_to_cpu(attr_b->nres.alloc_size));
1611 CLST evcn = le64_to_cpu(attr->nres.evcn);
1612
1613 if (end < next_svcn)
1614 end = next_svcn;
1615 while (end > evcn) {
1616 /* remove segment [svcn : evcn)*/
1617 mi_remove_attr(mi, attr);
1618
1619 if (!al_remove_le(ni, le)) {
1620 err = -EINVAL;
1621 goto out;
1622 }
1623
1624 if (evcn + 1 >= alloc) {
1625 /* last attribute segment */
1626 evcn1 = evcn + 1;
1627 goto ins_ext;
1628 }
1629
1630 if (ni_load_mi(ni, le, &mi)) {
1631 attr = NULL;
1632 goto out;
1633 }
1634
1635 attr = mi_find_attr(mi, NULL, ATTR_DATA, NULL, 0,
1636 &le->id);
1637 if (!attr) {
1638 err = -EINVAL;
1639 goto out;
1640 }
1641 svcn = le64_to_cpu(attr->nres.svcn);
1642 evcn = le64_to_cpu(attr->nres.evcn);
1643 }
1644
1645 if (end < svcn)
1646 end = svcn;
1647
1648 err = attr_load_runs(attr, ni, run, &end);
1649 if (err)
1650 goto out;
1651
1652 evcn1 = evcn + 1;
1653 attr->nres.svcn = cpu_to_le64(next_svcn);
1654 err = mi_pack_runs(mi, attr, run, evcn1 - next_svcn);
1655 if (err)
1656 goto out;
1657
1658 le->vcn = cpu_to_le64(next_svcn);
1659 ni->attr_list.dirty = true;
1660 mi->dirty = true;
1661
1662 next_svcn = le64_to_cpu(attr->nres.evcn) + 1;
1663 }
1664 ins_ext:
1665 if (evcn1 > next_svcn) {
1666 err = ni_insert_nonresident(ni, ATTR_DATA, NULL, 0, run,
1667 next_svcn, evcn1 - next_svcn,
1668 attr_b->flags, &attr, &mi);
1669 if (err)
1670 goto out;
1671 }
1672 ok:
1673 run_truncate_around(run, vcn);
1674 out:
1675 if (new_valid > data_size)
1676 new_valid = data_size;
1677
1678 valid_size = le64_to_cpu(attr_b->nres.valid_size);
^^^^^^^^^^^^^^^^^^^^^^^
Unchecked dereference
1679 if (new_valid != valid_size) {
1680 attr_b->nres.valid_size = cpu_to_le64(valid_size);
regards,
dan carpenter
