CVE-2026-43076
ocfs2: validate inline data i_size during inode read
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: validate inline data i_size during inode read
When reading an inode from disk, ocfs2_validate_inode_block() performs
various sanity checks but does not validate the size of inline data. If
the filesystem is corrupted, an inode's i_size can exceed the actual
inline data capacity (id_count).
This causes ocfs2_dir_foreach_blk_id() to iterate beyond the inline data
buffer, triggering a use-after-free when accessing directory entries from
freed memory.
In the syzbot report:
- i_size was 1099511627576 bytes (~1TB)
- Actual inline data capacity (id_count) is typically <256 bytes
- A garbage rec_len (54648) caused ctx->pos to jump out of bounds
- This triggered a UAF in ocfs2_check_dir_entry()
Fix by adding a validation check in ocfs2_validate_inode_block() to ensure
inodes with inline data have i_size <= id_count. This catches the
corruption early during inode read and prevents all downstream code from
operating on invalid data.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Produtos afetados
Linux · LinuxQuer saber se a sua infraestrutura está exposta a isto?
Falar com a TrueHacking →Referências
https://git.kernel.org/stable/c/131c0b573e1b467b7d553e9ff38003f1acd8f5f2https://git.kernel.org/stable/c/1524af3685b35feac76662cc551cbc37bd14775fhttps://git.kernel.org/stable/c/37f074e65f24f10f8d8df224a572e4cb9e6faf63https://git.kernel.org/stable/c/77d0295725109d77f5854ef5b58c0d06c08168cchttps://git.kernel.org/stable/c/bcd46bc261b215b3b12c557a978299eafa02ecddhttps://git.kernel.org/stable/c/c1de19e891be3bfb3e1d0c7cf07bbb8fb3b77c1bhttps://git.kernel.org/stable/c/cd2d765aa7157f852999842af32148128c735d39https://git.kernel.org/stable/c/d012c782abcabe68b5b9e71be58a15e9f9d83dc1