Detections
Analytics
CVE-2026-89573
high
Description
In the Linux kernel, the following vulnerability has been resolved: dm array: reject an array block whose value size is not the caller's array_block_check() can only compare the header against itself, so a block with value_size 4 and max_entries 1018 is internally consistent and passes. dm-cache keeps two arrays -- mappings at 8 bytes and hints at 4 -- and the roots for both live in the superblock. Point the mappings root at a hint block and __load_mappings() walks it through an info whose value size is 8, so element_at() strides 8 bytes over 4-byte entries and reaches offset 8160 of a 4096-byte block. get_ablock() and __shadow_ablock() are the two places that hold the block and the caller at once. Reject there when the two value sizes disagree. Arrays only ever read their own blocks, so this fires on crafted metadata only.
References
https://git.kernel.org/stable/c/cb409b38b0232ee4385ef55cddcd6fbdd011a8a2
https://git.kernel.org/stable/c/ac4a5eb8b002a0742c938fc98b922e243f53573a
https://git.kernel.org/stable/c/a8237cb8fa0a628d903e76635bfdeae4202036b9
https://git.kernel.org/stable/c/a530a9a419a7c5fdb7dae55ffa2dd7a130631842
https://git.kernel.org/stable/c/7bf4b5cb42a4e27f36bcbc6209d82a5da9c0168c
https://git.kernel.org/stable/c/522fa26da24ccaa298ebe3c1c97395d2d63dfc21
https://git.kernel.org/stable/c/4538a287bdf5d0f9a379c678e5262b9f5783f547
https://git.kernel.org/stable/c/35cd3b278448c79614f65ab6bbc9ed348d847df9