Currently, helpers that expect ARG_PTR_TO_MAP_KEY and ARG_PTR_TO_MAP_VALUE
can only access stack and packet memory. This patchset allows these
helpers to directly access map values by passing registers of type
PTR_TO_MAP_VALUE.

The first patch changes the verifier; the second adds new test cases.

The first three versions of this patchset were sent on the iovisor-dev
mailing list only.

Changelogs:
Changes in v5:
- Refactor using check_helper_mem_access.
Changes in v4:
- Rebase.
Changes in v3:
- Bug fixes.
- Negative test cases.
Changes in v2:
- Additional test cases for adjusted maps.

Paul Chaignon (2):
bpf: allow map helpers access to map values directly
tools/bpf: add verifier tests for accesses to map values

kernel/bpf/verifier.c | 24 +--
tools/testing/selftests/bpf/test_verifier.c | 266 ++++++++++++++++++++++++++++
2 files changed, 273 insertions(+), 17 deletions(-)

--
2.7.4

On 04/24/2018 03:06 PM, Paul Chaignon wrote:

Currently, helpers that expect ARG_PTR_TO_MAP_KEY and ARG_PTR_TO_MAP_VALUE
can only access stack and packet memory. This patchset allows these
helpers to directly access map values by passing registers of type
PTR_TO_MAP_VALUE.

The first patch changes the verifier; the second adds new test cases.

The first three versions of this patchset were sent on the iovisor-dev
mailing list only.

Changelogs:
Changes in v5:
- Refactor using check_helper_mem_access.
Changes in v4:
- Rebase.
Changes in v3:
- Bug fixes.
- Negative test cases.
Changes in v2:
- Additional test cases for adjusted maps.

Applied to bpf-next, thanks Paul!