CVE-2025-21994 Information

Description

In the Linux kernel the following vulnerability has been resolved:

ksmbd: fix incorrect validation for num_aces field of smb_acl

parse_dcal() validate num_aces to allocate posix_ace_state_array.

if (num_aces > ULONG_MAX / sizeof(struct smb_ace ))

It is an incorrect validation that we can create an array of size ULONG_MAX. smb_acl has ->size field to calculate actual number of aces in request buffer size. Use this to check invalid num_aces.

Reference

https://git.kernel.org/stable/c/1b8b67f3c5e5169535e26efedd3e422172e2db64 https://git.kernel.org/stable/c/9c4e202abff45f8eac17989e549fc7a75095f675 https://git.kernel.org/stable/c/a4cb17797a5d241f1e509cb5b46ed95a80c2f5fd https://git.kernel.org/stable/c/d0f87370622a853b57e851f7d5a5452b72300f19 https://git.kernel.org/stable/c/f6a6721802ac2f12f4c1bbe839a4c229b61866f2