Merge branch 'properly-load-values-from-insn_arays-with-non-zero-offsets'

Anton Protopopov says:

====================
Properly load values from insn_arays with non-zero offsets

The PTR_TO_INSN is always loaded via BPF_LDX_MEM instruction.
However, the verifier doesn't properly verify such loads when the
offset is not zero. Fix this and extend selftests with more scenarios.

v2 -> v3:
  * Add a C-level selftest which triggers a load with nonzero offset (Alexei)
  * Rephrase commit messages a bit

v2: https://lore.kernel.org/bpf/20260402184647.988132-1-a.s.protopopov@gmail.com/

v1: https://lore.kernel.org/bpf/20260401161529.681755-1-a.s.protopopov@gmail.com
====================

Link: https://patch.msgid.link/20260406160141.36943-1-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>