KFunc bpf_dynptr_slice_rdwr
Get a pointer to dynptr data up to len bytes for read write access.
Definition
If the dynptr doesn't have continuous data up to len bytes, or the dynptr is read only, return NULL.
void *bpf_dynptr_slice_rdwr(const struct bpf_dynptr_kern *ptr, u32 offset, void *buffer__opt, u32 buffer__szk)
Note
The pointer returned by the kfunc may be NULL. Hence, it forces the user to do a NULL check on the pointer returned from the kfunc before making use of it (dereferencing or passing to another helper).
Usage
Docs could be improved
This part of the docs is incomplete, contributions are very welcome
Program types
The following program types can make use of this kfunc:
- BPF_PROG_TYPE_CGROUP_SKB
- BPF_PROG_TYPE_CGROUP_SOCK_ADDR
- BPF_PROG_TYPE_LSM
- BPF_PROG_TYPE_LWT_IN
- BPF_PROG_TYPE_LWT_OUT
- BPF_PROG_TYPE_LWT_SEG6LOCAL
- BPF_PROG_TYPE_LWT_XMIT
- BPF_PROG_TYPE_NETFILTER
- BPF_PROG_TYPE_SCHED_ACT
- BPF_PROG_TYPE_SCHED_CLS
- BPF_PROG_TYPE_SK_SKB
- BPF_PROG_TYPE_SOCKET_FILTER
- BPF_PROG_TYPE_STRUCT_OPS
- BPF_PROG_TYPE_SYSCALL
- BPF_PROG_TYPE_TRACING
- BPF_PROG_TYPE_XDP
Example
Docs could be improved
This part of the docs is incomplete, contributions are very welcome