In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
ntfs3: bound to_move in indx_insert_into_root before hdr_insert_head<\/p>\n
indx_insert_into_root() promotes a full resident $INDEX_ROOT into
\n$INDEX_ALLOCATION and copies all non-last resident root entries into
\na newly allocated INDEX_BUFFER via hdr_insert_head(). The source
\nbyte count ‘to_move’ is summed from the on-disk resident entry sizes
\nand is independent of the destination buffer size, which comes from
\nroot->index_block_size (via indx->index_bits).<\/p>\n
A crafted NTFS image that keeps a valid, full resident root but
\nshrinks root->index_block_size down to 512 after the root has been
\npopulated makes hdr_insert_head() memcpy attacker-controlled resident
\nentry bytes past the end of the kmalloc(1u <index_bits)
\nallocation returned by indx_new(). For a 512-byte destination and a
\nresident root whose non-last entries total 560 bytes, the memcpy
\noverruns by 120 bytes and a following memmove extends the highest
\nwritten offset to 136 bytes past the allocation. The overflow bytes
\nare a direct copy of on-disk entries (via kmemdup), so they are
\nfully attacker-controlled.<\/p>\n
The write is reachable from unprivileged open(O_CREAT) on a mounted
\ncrafted NTFS image: a single sufficiently long create in a directory
\nwhose resident root is already full forces root promotion and
\ntriggers the copy.<\/p>\n
This is a controlled out-of-bounds write of 120-136 bytes past a
\nkmalloc(index_block_size) allocation, with attacker-controlled
\ncontent. It is a bounded adjacent-heap corruption primitive; it is
\nnot an arbitrary-address write. Successful exploitation into a named
\nvictim object depends on the surrounding slab layout.<\/p>\n
Reject the copy at the sink. The destination’s INDEX_HDR already
\nreports hdr_total (the payload capacity of the new buffer) and
\nhdr_used (the bytes already consumed by the terminal END entry
\ninstalled by indx_new()); require that to_move fits in the remaining
\npayload before calling hdr_insert_head(). On mismatch, fail with
\n-EINVAL and mark the filesystem as having a detected on-disk
\ninconsistency, which is the same behaviour as the surrounding
\nvalidation in this function.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
ntfs3: bound to_move in indx_insert_into_root before hdr_insert_head<\/p>\n
indx_insert_into_root() promotes a full resident $INDEX_ROOT <\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-6824","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/6824","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=6824"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6824"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6824"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}