1 files changed, 54 insertions, 1 deletions

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 623dd0684429..cea2ca6df949 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1012,7 +1012,7 @@ const struct bpf_func_proto bpf_snprintf_btf_proto = {
 BPF_CALL_1(bpf_get_func_ip_tracing, void *, ctx)
 {
 	/* This helper call is inlined by verifier. */
-	return ((u64 *)ctx)[-1];
+	return ((u64 *)ctx)[-2];
 }
 
 static const struct bpf_func_proto bpf_get_func_ip_proto_tracing = {
@@ -1091,6 +1091,53 @@ static const struct bpf_func_proto bpf_get_branch_snapshot_proto = {
 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
 };
 
+BPF_CALL_3(get_func_arg, void *, ctx, u32, n, u64 *, value)
+{
+	/* This helper call is inlined by verifier. */
+	u64 nr_args = ((u64 *)ctx)[-1];
+
+	if ((u64) n >= nr_args)
+		return -EINVAL;
+	*value = ((u64 *)ctx)[n];
+	return 0;
+}
+
+static const struct bpf_func_proto bpf_get_func_arg_proto = {
+	.func		= get_func_arg,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+	.arg2_type	= ARG_ANYTHING,
+	.arg3_type	= ARG_PTR_TO_LONG,
+};
+
+BPF_CALL_2(get_func_ret, void *, ctx, u64 *, value)
+{
+	/* This helper call is inlined by verifier. */
+	u64 nr_args = ((u64 *)ctx)[-1];
+
+	*value = ((u64 *)ctx)[nr_args];
+	return 0;
+}
+
+static const struct bpf_func_proto bpf_get_func_ret_proto = {
+	.func		= get_func_ret,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+	.arg2_type	= ARG_PTR_TO_LONG,
+};
+
+BPF_CALL_1(get_func_arg_cnt, void *, ctx)
+{
+	/* This helper call is inlined by verifier. */
+	return ((u64 *)ctx)[-1];
+}
+
+static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = {
+	.func		= get_func_arg_cnt,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+};
+
 static const struct bpf_func_proto *
 bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
@@ -1629,6 +1676,12 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		       NULL;
 	case BPF_FUNC_d_path:
 		return &bpf_d_path_proto;
+	case BPF_FUNC_get_func_arg:
+		return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_proto : NULL;
+	case BPF_FUNC_get_func_ret:
+		return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL;
+	case BPF_FUNC_get_func_arg_cnt:
+		return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL;
 	default:
 		fn = raw_tp_prog_func_proto(func_id, prog);
 		if (!fn && prog->expected_attach_type == BPF_TRACE_ITER)