tools/testing/selftests/bpf/progs/test_d_path.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include "vmlinux.h"
   4 #include <bpf/bpf_helpers.h>
   5 #include <bpf/bpf_tracing.h>
   6
   7 #define MAX_PATH_LEN            128
   8 #define MAX_FILES               7
   9
  10 pid_t my_pid = 0;
  11 __u32 cnt_stat = 0;
  12 __u32 cnt_close = 0;
  13 char paths_stat[MAX_FILES][MAX_PATH_LEN] = {};
  14 char paths_close[MAX_FILES][MAX_PATH_LEN] = {};
  15 int rets_stat[MAX_FILES] = {};
  16 int rets_close[MAX_FILES] = {};
  17
  18 int called_stat = 0;
  19 int called_close = 0;
  20
  21 SEC("fentry/security_inode_getattr")
  22 int BPF_PROG(prog_stat, struct path *path, struct kstat *stat,
  23              __u32 request_mask, unsigned int query_flags)
  24 {
  25         pid_t pid = bpf_get_current_pid_tgid() >> 32;
  26         __u32 cnt = cnt_stat;
  27         int ret;
  28
  29         called_stat = 1;
  30
  31         if (pid != my_pid)
  32                 return 0;
  33
  34         if (cnt >= MAX_FILES)
  35                 return 0;
  36         ret = bpf_d_path(path, paths_stat[cnt], MAX_PATH_LEN);
  37
  38         rets_stat[cnt] = ret;
  39         cnt_stat++;
  40         return 0;
  41 }
  42
  43 SEC("fentry/filp_close")
  44 int BPF_PROG(prog_close, struct file *file, void *id)
  45 {
  46         pid_t pid = bpf_get_current_pid_tgid() >> 32;
  47         __u32 cnt = cnt_close;
  48         int ret;
  49
  50         called_close = 1;
  51
  52         if (pid != my_pid)
  53                 return 0;
  54
  55         if (cnt >= MAX_FILES)
  56                 return 0;
  57         ret = bpf_d_path(&file->f_path,
  58                          paths_close[cnt], MAX_PATH_LEN);
  59
  60         rets_close[cnt] = ret;
  61         cnt_close++;
  62         return 0;
  63 }
  64
  65 char _license[] SEC("license") = "GPL";