mbox series

[bpf,v3,0/2] check bpf_func_state->callback_depth when pruning states

Message ID 20240222154121.6991-1-eddyz87@gmail.com (mailing list archive)
Headers show
Series check bpf_func_state->callback_depth when pruning states | expand

Message

Eduard Zingerman Feb. 22, 2024, 3:41 p.m. UTC 
This patch-set fixes bug in states pruning logic hit in mailing list
discussion [0]. The details of the fix are 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  (DIFF)
-------------------------  -------------  ---------------  --------------
pyperf600_bpf_loop.bpf.o   on_event          +15 (+0.42%)     +0 (+0.00%)
strobemeta_bpf_loop.bpf.o  on_event        +857 (+37.95%)   +60 (+38.96%)
xdp_synproxy_kern.bpf.o    syncookie_tc   +2892 (+30.39%)  +109 (+36.33%)
xdp_synproxy_kern.bpf.o    syncookie_xdp  +2892 (+30.01%)  +109 (+36.09%)

(when tested on a subset of selftests identified by
 selftests/bpf/veristat.cfg and Cilium bpf object files from [4])

Changelog:
v2 [2] -> v3:
- fixes for verifier.c commit message as suggested by Yonghong;
- patch-set re-rerouted to 'bpf' tree as suggested in [2];
- patch for test_tcp_custom_syncookie is sent separately to 'bpf-next' [3].
- veristat results updated using 'bpf' tree as baseline and clang 16.

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@linux.dev/
[1] https://lore.kernel.org/bpf/20240212143832.28838-1-eddyz87@gmail.com/
[2] https://lore.kernel.org/bpf/20240216150334.31937-1-eddyz87@gmail.com/
[3] https://lore.kernel.org/bpf/20240222150300.14909-1-eddyz87@gmail.com/
[4] https://github.com/anakryiko/cilium

Eduard Zingerman (2):
  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/verifier_iterating_callbacks.c  | 70 +++++++++++++++++++
 2 files changed, 73 insertions(+)

Comments

patchwork-bot+netdevbpf@kernel.org Feb. 22, 2024, 5:10 p.m. UTC | #1 
Hello:

This series was applied to bpf/bpf.git (master)
by Alexei Starovoitov <ast@kernel.org>:

On Thu, 22 Feb 2024 17:41:19 +0200 you wrote:
> This patch-set fixes bug in states pruning logic hit in mailing list
> discussion [0]. The details of the fix are 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:
> 
> [...]

Here is the summary with links:
  - [bpf,v3,1/2] bpf: check bpf_func_state->callback_depth when pruning states
    https://git.kernel.org/bpf/bpf/c/f31f0fe3d738
  - [bpf,v3,2/2] selftests/bpf: test case for callback_depth states pruning logic
    https://git.kernel.org/bpf/bpf/c/2861d07c5289

You are awesome, thank you!