This patch-set fixes bug in states pruning logic hit in mailing list discussion [0]. The details of the fix are in patch #2. A change to the test case test_tcp_custom_syncookie.c is necessary, otherwise updated verifier won't be able to process it due to instruction complexity limit. This change is done in patch #1. The main idea for the fix belongs to Yonghong Song, mine contribution is merely in review and test cases. There are some changes in verification performance: File Program Insns (DIFF) States (A) States (B) States (DIFF) ------------------------- -------- -------------- ---------- ---------- ------------- pyperf600_bpf_loop.bpf.o on_event +53 (+1.09%) 323 330 +7 (+2.17%) strobemeta_bpf_loop.bpf.o on_event +594 (+27.85%) 163 213 +50 (+30.67%) (when tested using BPF selftests and Cilium object files) Changelog: v1 [1] -> v2: - patch #2 commit message updated to better reflect verifier behavior with regards to checkpoints tree (suggested by Yonghong); - veristat results added (suggested by Andrii). [0] https://lore.kernel.org/bpf/9b251840-7cb8-4d17-bd23-1fc8071d8eef@xxxxxxxxx/ [1] https://lore.kernel.org/bpf/20240212143832.28838-1-eddyz87@xxxxxxxxx/ Eduard Zingerman (3): selftests/bpf: update tcp_custom_syncookie to use scalar packet offset bpf: check bpf_func_state->callback_depth when pruning states selftests/bpf: test case for callback_depth states pruning logic kernel/bpf/verifier.c | 3 + .../bpf/progs/test_tcp_custom_syncookie.c | 83 ++++++++++++------- .../bpf/progs/verifier_iterating_callbacks.c | 70 ++++++++++++++++ 3 files changed, 126 insertions(+), 30 deletions(-) -- 2.43.0
