[PATCH bpf-next 0/3] bpf: consolidate pointer offset tracking in var_off

[Eduard Zingerman <eddyz87@gmail.com>]

Consolidate static and varying pointer offset tracking logic in the
BPF verifier. All pointer offsets are now represented solely using
`reg->var_off` and min/max fields, simplifying pointer tracking code
and making it easier to widen pointer registers for loop convergence
checks.

Patch 1 is a preparatory refactoring of check_reg_sane_offset().
Patch 2 is the main change, moving pointer offsets from `reg->off`
  to `reg->var_off`.
Patch 3 renames the now-repurposed `reg->off` field to `reg->delta`,
  reflecting its remaining role as a constant delta between linked
  scalar registers.

---
Eduard Zingerman (3):
      bpf: split check_reg_sane_offset() in two parts
      bpf: use reg->var_off instead of reg->off for pointers
      bpf: rename bpf_reg_state->off to bpf_reg_state->delta

 include/linux/bpf_verifier.h                       |   5 +-
 kernel/bpf/log.c                                   |  10 +-
 kernel/bpf/verifier.c                              | 363 +++++++++------------
 .../testing/selftests/bpf/prog_tests/linked_list.c |   4 +-
 .../selftests/bpf/progs/exceptions_assert.c        |   2 +-
 tools/testing/selftests/bpf/progs/iters.c          |   6 +-
 .../selftests/bpf/progs/mem_rdonly_untrusted.c     |   2 +-
 tools/testing/selftests/bpf/progs/verifier_align.c |  40 +--
 .../testing/selftests/bpf/progs/verifier_bounds.c  |   2 +-
 .../bpf/progs/verifier_direct_packet_access.c      |   4 +-
 tools/testing/selftests/bpf/progs/verifier_gotox.c |   4 +-
 .../bpf/progs/verifier_helper_packet_access.c      |   2 +-
 .../bpf/progs/verifier_helper_value_access.c       |   4 +-
 .../testing/selftests/bpf/progs/verifier_int_ptr.c |   2 +-
 .../selftests/bpf/progs/verifier_meta_access.c     |   2 +-
 .../selftests/bpf/progs/verifier_spill_fill.c      |   8 +-
 .../selftests/bpf/progs/verifier_stack_ptr.c       |   4 +-
 .../selftests/bpf/progs/verifier_value_ptr_arith.c |  10 +-
 .../bpf/progs/verifier_xdp_direct_packet_access.c  |  64 ++--
 tools/testing/selftests/bpf/verifier/calls.c       |   2 +-
 20 files changed, 235 insertions(+), 305 deletions(-)
---
base-commit: 4475cdac12c46fc26ee815de1b43cfe9f8375140
change-id: 20260211-ptrs-off-migration-9ad00d0c3f93