[PATCH 0/3] Dynptr Verifier Adjustments

From: Daniel Rosenberg
Date: Wed Apr 05 2023 - 20:40:47 EST


These patches relax a few verifier requirements around dynptrs.

I was unable to test the patch in 0003 due to unrelated issues compiling the
bpf selftests, but did run an equivalent local test program.

This is the issue I was running into:
progs/cgrp_ls_attach_cgroup.c:17:15: error: use of undeclared identifier 'BPF_MAP_TYPE_CGRP_STORAGE'; did you mean 'BPF_MAP_TYPE_CGROUP_STORAGE'?
__uint(type, BPF_MAP_TYPE_CGRP_STORAGE);
^~~~~~~~~~~~~~~~~~~~~~~~~
BPF_MAP_TYPE_CGROUP_STORAGE
/ssd/kernel/fuse-bpf/tools/testing/selftests/bpf/tools/include/bpf/bpf_helpers.h:13:39: note: expanded from macro '__uint'
#define __uint(name, val) int (*name)[val]
^
/ssd/kernel/fuse-bpf/tools/testing/selftests/bpf/tools/include/vmlinux.h:27892:2: note: 'BPF_MAP_TYPE_CGROUP_STORAGE' declared here
BPF_MAP_TYPE_CGROUP_STORAGE = 19,
^
1 error generated.

Daniel Rosenberg (3):
bpf: verifier: Accept dynptr mem as mem in helpers
bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)
selftests/bpf: Test allowing NULL buffer in dynptr slice

Documentation/bpf/kfuncs.rst | 23 ++++++++++++-
kernel/bpf/helpers.c | 32 ++++++++++++-------
kernel/bpf/verifier.c | 21 ++++++++++++
.../testing/selftests/bpf/prog_tests/dynptr.c | 1 +
.../selftests/bpf/progs/dynptr_success.c | 21 ++++++++++++
5 files changed, 85 insertions(+), 13 deletions(-)


base-commit: 5af607a861d43ffff830fc1890033e579ec44799
--
2.40.0.577.gac1e443424-goog