This makes bpf_dynptr_from_skb usable for tp_btf, so that we can easily parse skb in tracepoints. This has been discussed in [0], and Martin suggested to use dynptr (instead of helpers like bpf_skb_load_bytes). For safety, skb dynptr shouldn't be used in fentry/fexit. This is achieved by add KF_TRUSTED_ARGS flag in bpf_dynptr_from_skb defination. IIUC, the flag can be added to current defination directly, because skb is always passed from ctx. But I'm not definitely sure about this. Please tell me if there is any problem. Thanks in advance. Selftests are expanded with skb dynptr used in tp_btf. They also make sure that skb dynptr cannot be used in fentry/fexit. [0] https://lore.kernel.org/all/20240205121038.41344-1-lulie@xxxxxxxxxxxxxxxxx/T/ Philo Lu (2): bpf: Allow bpf_dynptr_from_skb() for tp_btf selftests/bpf: Expand skb dynptr selftests for tp_btf net/core/filter.c | 3 +- .../testing/selftests/bpf/prog_tests/dynptr.c | 36 +++++++++++++++++-- .../testing/selftests/bpf/progs/dynptr_fail.c | 25 +++++++++++++ .../selftests/bpf/progs/dynptr_success.c | 23 ++++++++++++ 4 files changed, 84 insertions(+), 3 deletions(-) -- 2.32.0.3.g01195cf9f
