From: Jiri Olsa <jolsa@kernel.org>
Date: Wed, 16 Mar 2022 13:24:10 +0100
Subject: bpf: Add bpf_get_func_ip kprobe helper for multi kprobe link
Patch-mainline: v5.18-rc1
Git-commit: 42a5712094e89ef0a125ac0f9d0873f9233368b1
References: jsc#PED-1377
Adding support to call bpf_get_func_ip helper from kprobe
programs attached by multi kprobe link.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-5-jolsa@kernel.org
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
kernel/trace/bpf_trace.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1037,6 +1037,18 @@ static const struct bpf_func_proto bpf_g
.arg1_type = ARG_PTR_TO_CTX,
};
+BPF_CALL_1(bpf_get_func_ip_kprobe_multi, struct pt_regs *, regs)
+{
+ return instruction_pointer(regs);
+}
+
+static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe_multi = {
+ .func = bpf_get_func_ip_kprobe_multi,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+};
+
BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx)
{
struct bpf_trace_run_ctx *run_ctx;
@@ -1280,7 +1292,9 @@ kprobe_prog_func_proto(enum bpf_func_id
return &bpf_override_return_proto;
#endif
case BPF_FUNC_get_func_ip:
- return &bpf_get_func_ip_proto_kprobe;
+ return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ?
+ &bpf_get_func_ip_proto_kprobe_multi :
+ &bpf_get_func_ip_proto_kprobe;
case BPF_FUNC_get_attach_cookie:
return &bpf_get_attach_cookie_proto_trace;
default: