CVE-2026-89779

In the Linux kernel, the following vulnerability has been resolved:

fs/ntfs3: validate ef->size covers the record's name and value

When an EA record has a non-zero ef->size, ntfsreadea() only checks

that the record fits in the remaining buffer (ea_size > bytes), not that

ef->size is large enough to hold the record's own name_len + 1 + elength.

A crafted image can pass validation with, e.g., ef->size = 24 but

elength = 0xffff. ntfsgetea() then trusts elength and copies it out of

the undersized record, reading past the kmalloc(info->size) allocation

and leaking heap memory to userspace via getxattr():

 BUG: KASAN: slab-out-of-bounds in ntfsgetea (fs/ntfs3/xattr.c:302)

 Read of size 65535 at addr ffff888100794550 by task exploit

  _asanmemcpy (mm/kasan/shadow.c:105)

  ntfsgetea (fs/ntfs3/xattr.c:302)

  ntfs_getxattr (fs/ntfs3/xattr.c:848)

  _vfsgetxattr (fs/xattr.c:441)

  vfs_getxattr (fs/xattr.c:474)

  do_getxattr (fs/xattr.c:800)

  path_getxattrat (fs/xattr.c:868)

  dosyscall64 (arch/x86/entry/syscall_64.c:94)

 The buggy address is located 80 bytes inside of

  allocated 84-byte region in cache kmalloc-96

Compute the size the record needs and require ef->size to cover it.