On 9/5/24 12:56 AM, Philo Lu wrote:
Making tp_btf able to use bpf_dynptr_from_skb(), which is useful for skb parsing, especially for non-linear paged skb data. This is achieved by adding KF_TRUSTED_ARGS flag to bpf_dynptr_from_skb and registering it for TRACING progs. With KF_TRUSTED_ARGS, args from fentry/fexit are excluded, so that unsafe progs like fexit/__kfree_skb are not allowed. We also need the skb dynptr to be read-only in tp_btf. Because may_access_direct_pkt_data() returns false by default when checking bpf_dynptr_from_skb, there is no need to add BPF_PROG_TYPE_TRACING to it explicitly.
Acked-by: Martin KaFai Lau <martin.lau@xxxxxxxxxx>
