CVE-2026-90226

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

nfc: llcp: avoid userspace overflow on invalid optlen

nfc_llcp_getsockopt() casts optval to (u32 __user *) for put_user(), so

the kernel always stores 4 bytes regardless of the caller-supplied

optlen. The existing min_t(u32, len, sizeof(u32)) only clamps the length

reported back to userspace; it does not constrain the store. A call with

optlen < 4 therefore writes past the user buffer, violating the

getsockopt(2) contract for all five supported optnames.

Reject any call with optlen < sizeof(u32) up front. 'len' is int, so a

plain size comparison would promote a negative optlen to size_t and slip

past the check; an explicit 'len < 0' test is added first to catch

negative values before the size compare.