[PATCH bpf-next v2 0/2] bpf: Disallow BPF_F_LOCK with mixed special fields

[Leon Hwang <leon.hwang@linux.dev>]

Disallow combining BPF_F_LOCK with map values that mix bpf_spin_lock and
other special BTF fields, which may lead to undefined behavior. Such cases
are now rejected with -EOPNOTSUPP.

Map update flag validation is centralized in
bpf_map_check_op_flags() and reused across array, hash, local-storage,
and task-storage update paths, with selftests added to verify the new
behavior.

Changes:
v1 -> v2:
* Reject any unknown flag bits in map_flags when updating maps (per AI review).
* v1: https://lore.kernel.org/bpf/20260122153120.69249-1-leon.hwang@linux.dev/

Leon Hwang (2):
  bpf: Disallow BPF_F_LOCK with mixed special fields and centralize flag
    checks
  selftests/bpf: Add tests to verify BPF_F_LOCK restrictions

 include/linux/bpf.h                           |  7 ++
 kernel/bpf/arraymap.c                         | 11 ++-
 kernel/bpf/bpf_local_storage.c                |  7 --
 kernel/bpf/bpf_task_storage.c                 |  3 -
 kernel/bpf/hashtab.c                          |  8 +--
 kernel/bpf/syscall.c                          |  4 +-
 .../selftests/bpf/prog_tests/map_lock.c       | 70 +++++++++++++++++++
 .../selftests/bpf/progs/test_map_lock.c       | 31 +++++++-
 8 files changed, 117 insertions(+), 24 deletions(-)

--
2.52.0