CVE-2025-40050

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

bpf: Skip scalar adjustment for BPF_NEG if dst is a pointer

In check_alu_op(), the verifier currently calls check_reg_arg() and
adjust_scalar_min_max_vals() unconditionally for BPF_NEG operations.
However, if the destination register holds a pointer, these scalar
adjustments are unnecessary and potentially incorrect.

This patch adds a check to skip the adjustment logic when the destination
register contains a pointer.