CVE-2026-63815
CVE-2026-63815CVE-2026-63815
Description
In the Linux kernel, the following vulnerability has been resolved:
f2fs: bound i_inline_xattr_size for non-inline-xattr inodes
When the flexible_inline_xattr feature is enabled, do_read_inode() loads
the on-disk i_inline_xattr_size unconditionally:
if (f2fs_sb_has_flexible_inline_xattr(sbi))
fi->i_inline_xattr_size = le16_to_cpu(ri->i_inline_xattr_size);
but sanity_check_inode() only range-checks it when the inode also has the
FI_INLINE_XATTR flag set. An inode that carries an inline dentry or inline
data but not FI_INLINE_XATTR -- the normal layout for an inline
directory -- therefore keeps a fully attacker-controlled
i_inline_xattr_size from a crafted image.
get_inline_xattr_addrs() returns that value with no flag gating, so it
feeds the inode geometry:
MAX_INLINE_DATA() = 4 * (CUR_ADDRS_PER_INODE - i_inline_xattr_size - 1)
NR_INLINE_DENTRY() = MAX_INLINE_DATA() * BITS_PER_BYTE / (...)
addrs_per_page() = CUR_ADDRS_PER_INODE - i_inline_xattr_size
A large i_inline_xat
Scoring
| Last modified | 2026-07-19 |