In the Linux kernel, the following vulnerability has been resolved:
ntfs: fix off-by-one in mapping pairs decoding bounds checks
In ntfs_mapping_pairs_decompress(), attr_end points one byte past the
end of the attribute record:
attr_end = (u8 *)attr + le32_to_cpu(attr->length);
The two bounds checks validating that mapping pair data bytes fit within
the attribute use strict greater-than (>), which allows a one-byte
out-of-bounds read when the data extends exactly to attr_end:
b = *buf & 0xf;
if (b) {
if (unlikely(buf + b > attr_end)) // off-by-one
goto io_error;
for (deltaxcn = (s8)buf[b–]; b; b–)
deltaxcn = (deltaxcn <= so that buf[b] at exactly attr_end is
correctly rejected as out of bounds.
