1 #include <stdio.h> 2 #include <linux/bpf.h> 3 #include <unistd.h> 4 #include <linux/filter.h> 5 #include <linux/seccomp.h> 6 #include <sys/prctl.h> 7 #include "libbpf.h" 8 #include "bpf_load.h" 9 10 /* install fake seccomp program to enable seccomp code path inside the kernel, 11 * so that our kprobe attached to seccomp_phase1() can be triggered 12 */ 13 static void install_accept_all_seccomp(void) 14 { 15 struct sock_filter filter[] = { 16 BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW), 17 }; 18 struct sock_fprog prog = { 19 .len = (unsigned short)(sizeof(filter)/sizeof(filter[0])), 20 .filter = filter, 21 }; 22 if (prctl(PR_SET_SECCOMP, 2, &prog)) 23 perror("prctl"); 24 } 25 26 int main(int ac, char **argv) 27 { 28 FILE *f; 29 char filename[256]; 30 31 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); 32 33 if (load_bpf_file(filename)) { 34 printf("%s", bpf_log_buf); 35 return 1; 36 } 37 38 install_accept_all_seccomp(); 39 40 f = popen("dd if=/dev/zero of=/dev/null count=5", "r"); 41 (void) f; 42 43 read_trace_pipe(); 44 45 return 0; 46 } 47