bpf/progs/kprobe_multi.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 #include <linux/bpf.h>
0003 #include <bpf/bpf_helpers.h>
0004 #include <bpf/bpf_tracing.h>
0005 #include <stdbool.h>
0006
0007 char _license[] SEC("license") = "GPL";
0008
0009 extern const void bpf_fentry_test1 __ksym;
0010 extern const void bpf_fentry_test2 __ksym;
0011 extern const void bpf_fentry_test3 __ksym;
0012 extern const void bpf_fentry_test4 __ksym;
0013 extern const void bpf_fentry_test5 __ksym;
0014 extern const void bpf_fentry_test6 __ksym;
0015 extern const void bpf_fentry_test7 __ksym;
0016 extern const void bpf_fentry_test8 __ksym;
0017
0018 int pid = 0;
0019 bool test_cookie = false;
0020
0021 __u64 kprobe_test1_result = 0;
0022 __u64 kprobe_test2_result = 0;
0023 __u64 kprobe_test3_result = 0;
0024 __u64 kprobe_test4_result = 0;
0025 __u64 kprobe_test5_result = 0;
0026 __u64 kprobe_test6_result = 0;
0027 __u64 kprobe_test7_result = 0;
0028 __u64 kprobe_test8_result = 0;
0029
0030 __u64 kretprobe_test1_result = 0;
0031 __u64 kretprobe_test2_result = 0;
0032 __u64 kretprobe_test3_result = 0;
0033 __u64 kretprobe_test4_result = 0;
0034 __u64 kretprobe_test5_result = 0;
0035 __u64 kretprobe_test6_result = 0;
0036 __u64 kretprobe_test7_result = 0;
0037 __u64 kretprobe_test8_result = 0;
0038
0039 extern bool CONFIG_X86_KERNEL_IBT __kconfig __weak;
0040
0041 static void kprobe_multi_check(void *ctx, bool is_return)
0042 {
0043     if (bpf_get_current_pid_tgid() >> 32 != pid)
0044         return;
0045
0046     __u64 cookie = test_cookie ? bpf_get_attach_cookie(ctx) : 0;
0047     __u64 addr = bpf_get_func_ip(ctx) - (CONFIG_X86_KERNEL_IBT ? 4 : 0);
0048
0049 #define SET(__var, __addr, __cookie) ({         \
0050     if (((const void *) addr == __addr) &&      \
0051          (!test_cookie || (cookie == __cookie)))    \
0052         __var = 1;              \
0053 })
0054
0055     if (is_return) {
0056         SET(kretprobe_test1_result, &bpf_fentry_test1, 8);
0057         SET(kretprobe_test2_result, &bpf_fentry_test2, 2);
0058         SET(kretprobe_test3_result, &bpf_fentry_test3, 7);
0059         SET(kretprobe_test4_result, &bpf_fentry_test4, 6);
0060         SET(kretprobe_test5_result, &bpf_fentry_test5, 5);
0061         SET(kretprobe_test6_result, &bpf_fentry_test6, 4);
0062         SET(kretprobe_test7_result, &bpf_fentry_test7, 3);
0063         SET(kretprobe_test8_result, &bpf_fentry_test8, 1);
0064     } else {
0065         SET(kprobe_test1_result, &bpf_fentry_test1, 1);
0066         SET(kprobe_test2_result, &bpf_fentry_test2, 7);
0067         SET(kprobe_test3_result, &bpf_fentry_test3, 2);
0068         SET(kprobe_test4_result, &bpf_fentry_test4, 3);
0069         SET(kprobe_test5_result, &bpf_fentry_test5, 4);
0070         SET(kprobe_test6_result, &bpf_fentry_test6, 5);
0071         SET(kprobe_test7_result, &bpf_fentry_test7, 6);
0072         SET(kprobe_test8_result, &bpf_fentry_test8, 8);
0073     }
0074
0075 #undef SET
0076 }
0077
0078 /*
0079  * No tests in here, just to trigger 'bpf_fentry_test*'
0080  * through tracing test_run
0081  */
0082 SEC("fentry/bpf_modify_return_test")
0083 int BPF_PROG(trigger)
0084 {
0085     return 0;
0086 }
0087
0088 SEC("kprobe.multi/bpf_fentry_tes??")
0089 int test_kprobe(struct pt_regs *ctx)
0090 {
0091     kprobe_multi_check(ctx, false);
0092     return 0;
0093 }
0094
0095 SEC("kretprobe.multi/bpf_fentry_test*")
0096 int test_kretprobe(struct pt_regs *ctx)
0097 {
0098     kprobe_multi_check(ctx, true);
0099     return 0;
0100 }
0101
0102 SEC("kprobe.multi")
0103 int test_kprobe_manual(struct pt_regs *ctx)
0104 {
0105     kprobe_multi_check(ctx, false);
0106     return 0;
0107 }
0108
0109 SEC("kretprobe.multi")
0110 int test_kretprobe_manual(struct pt_regs *ctx)
0111 {
0112     kprobe_multi_check(ctx, true);
0113     return 0;
0114 }