KFunc `bpf_put_file`

This function puts a reference on the supplied file.

Definition

Put a reference on the supplied file. Only referenced file pointers may be passed to this BPF kfunc. Attempting to pass an unreferenced file pointer, or any other arbitrary pointer for that matter, will result in the BPF program being rejected by the BPF verifier.

This BPF kfunc may only be called from BPF LSM programs.

Parameters

file: file to put a reference on

Signature

void bpf_put_file(struct file *file)

Note

This kfunc releases the pointer passed in to it. There can be only one referenced pointer that can be passed in. All copies of the pointer being released are invalidated as a result of invoking this kfunc.

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_LSM

Example