idpf: bound interrupt-vector register fill to the allocated array

idpf: bound interrupt-vector register fill to the allocated array

idpf_get_reg_intr_vecs() fills the caller-allocated reg_vals[] array from
the VIRTCHNL2_OP_ALLOC_VECTORS reply in adapter->req_vec_chunks, bounding
its inner loop only by the per-chunk num_vectors. The array is sized
separately: idpf_intr_reg_init() allocates
kzalloc_objs(struct idpf_vec_regs, total_vecs) from
caps.num_allocated_vectors and only checks the returned count after the
fill. The sum of per-chunk num_vectors is never reconciled against
total_vecs, so a reply with a small num_allocated_vectors but chunks
summing higher writes past the end of reg_vals[].

Impact: a control plane (a PF or hypervisor device model) that returns a
VIRTCHNL2_OP_ALLOC_VECTORS reply whose per-chunk num_vectors sum exceeds
num_allocated_vectors writes struct idpf_vec_regs entries past the end of
the reg_vals kmalloc allocation (KASAN slab-out-of-bounds write).

Bound the fill loop to the array capacity passed in by the callers,
mirroring the sibling idpf_vport_get_q_reg(). The existing
num_regs < num_vecs check then rejects an undersized reply without the
out-of-bounds write happening first.

Fixes: d4d558718266 ("idpf: initialize interrupts and enable vport")
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>