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:764 attr_set_size()
error: we previously assumed 'le' could be null (see line 703)
fs/ntfs3/attrib.c
702 goto out;
703 } else if (le && le->vcn) {
^^
This code assumes "le" can be NULL.
704 u16 le_sz = le16_to_cpu(le->size);
705
706 /*
707 * NOTE: list entries for one attribute are always
708 * the same size. We deal with last entry (vcn==0)
709 * and it is not first in entries array
710 * (list entry for std attribute always first)
711 * So it is safe to step back
712 */
713 mi_remove_attr(mi, attr);
714
715 if (!al_remove_le(ni, le)) {
716 err = -EINVAL;
717 goto out;
718 }
719
720 le = (struct ATTR_LIST_ENTRY *)((u8 *)le - le_sz);
721 } else {
722 attr->nres.evcn = cpu_to_le64((u64)vcn - 1);
723 mi->dirty = true;
724 }
725
726 attr_b->nres.alloc_size = cpu_to_le64(new_alloc_tmp);
727
728 if (vcn == new_alen) {
729 attr_b->nres.data_size = cpu_to_le64(new_size);
730 if (new_size < old_valid)
731 attr_b->nres.valid_size =
732 attr_b->nres.data_size;
733 } else {
734 if (new_alloc_tmp <=
735 le64_to_cpu(attr_b->nres.data_size))
736 attr_b->nres.data_size =
737 attr_b->nres.alloc_size;
738 if (new_alloc_tmp <
739 le64_to_cpu(attr_b->nres.valid_size))
740 attr_b->nres.valid_size =
741 attr_b->nres.alloc_size;
742 }
743
744 if (is_ext)
745 le64_sub_cpu(&attr_b->nres.total_size,
746 ((u64)alen << cluster_bits));
747
748 mi_b->dirty = true;
749
750 if (new_alloc_tmp <= new_alloc)
751 goto ok;
752
753 old_size = new_alloc_tmp;
754 vcn = svcn - 1;
755
756 if (le == le_b) {
757 attr = attr_b;
758 mi = mi_b;
759 evcn = svcn - 1;
760 svcn = 0;
761 goto next_le;
762 }
763
764 if (le->type != type || le->name_len != name_len ||
^^^^^^^^
Unchecked dereference.
765 memcmp(le_name(le), name, name_len * sizeof(short))) {
766 err = -EINVAL;
regards,
dan carpenter
