CVE-2025-22039

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

ksmbd: fix overflow in dacloffset bounds check

The dacloffset field was originally typed as int and used in an unchecked addition, which could overflow and bypass the existing bounds check in both smb_check_perm_dacl() and smb_inherit_dacl().

This could result in out-of-bounds memory access and a kernel crash when dereferencing the DACL pointer.

This patch converts dacloffset to unsigned int and uses check_add_overflow() to validate access to the DACL.

Red Hat Enterprise Linux and derived products are not affected by this vulnerability because the in-kernel SMB server (ksmbd) is neither enabled nor compiled in supported Red Hat kernels. The flaw involves an arithmetic overflow during access control list parsing within ksmbd, which could allow an attacker to cause an invalid memory read or system crash on configurations running this service. Supported Red Hat environments provide SMB file sharing exclusively through userspace Samba, completely eliminating exposure to this kernel flaw.