| // SPDX-License-Identifier: GPL-2.0 |
| |
| #include "vmlinux.h" |
| #include <bpf/bpf_helpers.h> |
| #include <bpf/bpf_tracing.h> |
| |
| extern const int bpf_prog_active __ksym; |
| |
| struct { |
| __uint(type, BPF_MAP_TYPE_RINGBUF); |
| __uint(max_entries, 1 << 12); |
| } ringbuf SEC(".maps"); |
| |
| SEC("fentry/security_inode_getattr") |
| int BPF_PROG(d_path_check_rdonly_mem, struct path *path, struct kstat *stat, |
| __u32 request_mask, unsigned int query_flags) |
| { |
| void *active; |
| u32 cpu; |
| |
| cpu = bpf_get_smp_processor_id(); |
| active = (void *)bpf_per_cpu_ptr(&bpf_prog_active, cpu); |
| if (active) { |
| /* FAIL here! 'active' points to 'regular' memory. It |
| * cannot be submitted to ring buffer. |
| */ |
| bpf_ringbuf_submit(active, 0); |
| } |
| return 0; |
| } |
| |
| char _license[] SEC("license") = "GPL"; |