On 4/24/23 9:04 AM, Jiri Olsa wrote:
Adding support to specify cookies array for uprobe_multi link.
The cookies array share indexes and length with other uprobe_multi
arrays (paths/offsets/ref_ctr_offsets).
The cookies[i] value defines cookie for i-the uprobe and will be
returned by bpf_get_attach_cookie helper when called from ebpf
program hooked to that specific uprobe.
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
include/uapi/linux/bpf.h | 1 +
kernel/bpf/syscall.c | 2 +-
kernel/trace/bpf_trace.c | 46 +++++++++++++++++++++++++++++++++++++---
3 files changed, 45 insertions(+), 4 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index debc041c6ca5..77ce2159478d 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1581,6 +1581,7 @@ union bpf_attr {
__aligned_u64 paths;
__aligned_u64 offsets;
__aligned_u64 ref_ctr_offsets;
+ __aligned_u64 cookies;
} uprobe_multi;
};
} link_create;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 0b789a33317b..5b2dc7ae8616 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -4566,7 +4566,7 @@ static int bpf_map_do_batch(const union bpf_attr *attr,
return err;
}
-#define BPF_LINK_CREATE_LAST_FIELD link_create.kprobe_multi.cookies
+#define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.cookies
static int link_create(union bpf_attr *attr, bpfptr_t uattr)
{
enum bpf_prog_type ptype;
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index b84a7d01abf4..f795cfc00e5f 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -87,6 +87,8 @@ static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx);
static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
+static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx);
+
/**
* trace_call_bpf - invoke BPF program
* @call: tracepoint event
@@ -1089,6 +1091,18 @@ static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = {
.arg1_type = ARG_PTR_TO_CTX,
};
+BPF_CALL_1(bpf_get_attach_cookie_uprobe_multi, struct pt_regs *, regs)
+{
+ return bpf_uprobe_multi_cookie(current->bpf_ctx);
+}
the argument regs is not used here.
looks like we have the same issue for
bpf_get_attach_cookie_kprobe_multi
bpf_get_attach_cookie_trace
bpf_get_attach_cookie_tracing
I think this probably for preserving uapi. So I am okay with
the above, just want to point it out.
+
+static const struct bpf_func_proto bpf_get_attach_cookie_proto_umulti = {
+ .func = bpf_get_attach_cookie_uprobe_multi,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+};
+
[...]
