1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/bpf.h> 3 #include <bpf/bpf_helpers.h> 4 #include <bpf/bpf_tracing.h> 5 #include <stdbool.h> 6 #include "bpf_kfuncs.h" 7 #include "bpf_misc.h" 8 9 char _license[] SEC("license") = "GPL"; 10 11 extern const void bpf_fentry_test1 __ksym; 12 extern const void bpf_fentry_test2 __ksym; 13 extern const void bpf_fentry_test3 __ksym; 14 extern const void bpf_fentry_test4 __ksym; 15 extern const void bpf_fentry_test5 __ksym; 16 extern const void bpf_fentry_test6 __ksym; 17 extern const void bpf_fentry_test7 __ksym; 18 extern const void bpf_fentry_test8 __ksym; 19 20 int pid = 0; 21 22 __u64 kprobe_session_result[8]; 23 24 static int session_check(void *ctx) 25 { 26 unsigned int i; 27 __u64 addr; 28 const void *kfuncs[] = { 29 &bpf_fentry_test1, 30 &bpf_fentry_test2, 31 &bpf_fentry_test3, 32 &bpf_fentry_test4, 33 &bpf_fentry_test5, 34 &bpf_fentry_test6, 35 &bpf_fentry_test7, 36 &bpf_fentry_test8, 37 }; 38 39 if (bpf_get_current_pid_tgid() >> 32 != pid) 40 return 1; 41 42 addr = bpf_get_func_ip(ctx); 43 44 for (i = 0; i < ARRAY_SIZE(kfuncs); i++) { 45 if (kfuncs[i] == (void *) addr) { 46 kprobe_session_result[i]++; 47 break; 48 } 49 } 50 51 /* 52 * Force probes for function bpf_fentry_test[5-8] not to 53 * install and execute the return probe 54 */ 55 if (((const void *) addr == &bpf_fentry_test5) || 56 ((const void *) addr == &bpf_fentry_test6) || 57 ((const void *) addr == &bpf_fentry_test7) || 58 ((const void *) addr == &bpf_fentry_test8)) 59 return 1; 60 61 return 0; 62 } 63 64 /* 65 * No tests in here, just to trigger 'bpf_fentry_test*' 66 * through tracing test_run 67 */ 68 SEC("fentry/bpf_modify_return_test") 69 int BPF_PROG(trigger) 70 { 71 return 0; 72 } 73 74 SEC("kprobe.session/bpf_fentry_test*") 75 int test_kprobe(struct pt_regs *ctx) 76 { 77 return session_check(ctx); 78 } 79