bpf: Store ref_ctr_offsets values in bpf_uprobe array
We will need to return ref_ctr_offsets values through link_info
interface in following change, so we need to keep them around.
Storing ref_ctr_offsets values directly into bpf_uprobe array.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20231125193130.834322-3-jolsa@kernel.org
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index f0b8b7c..ad0323f 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3033,6 +3033,7 @@ struct bpf_uprobe_multi_link;
struct bpf_uprobe {
struct bpf_uprobe_multi_link *link;
loff_t offset;
+ unsigned long ref_ctr_offset;
u64 cookie;
struct uprobe_consumer consumer;
};
@@ -3172,7 +3173,6 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
{
struct bpf_uprobe_multi_link *link = NULL;
unsigned long __user *uref_ctr_offsets;
- unsigned long *ref_ctr_offsets = NULL;
struct bpf_link_primer link_primer;
struct bpf_uprobe *uprobes = NULL;
struct task_struct *task = NULL;
@@ -3245,18 +3245,12 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
if (!uprobes || !link)
goto error_free;
- if (uref_ctr_offsets) {
- ref_ctr_offsets = kvcalloc(cnt, sizeof(*ref_ctr_offsets), GFP_KERNEL);
- if (!ref_ctr_offsets)
- goto error_free;
- }
-
for (i = 0; i < cnt; i++) {
if (ucookies && __get_user(uprobes[i].cookie, ucookies + i)) {
err = -EFAULT;
goto error_free;
}
- if (uref_ctr_offsets && __get_user(ref_ctr_offsets[i], uref_ctr_offsets + i)) {
+ if (uref_ctr_offsets && __get_user(uprobes[i].ref_ctr_offset, uref_ctr_offsets + i)) {
err = -EFAULT;
goto error_free;
}
@@ -3287,7 +3281,7 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
for (i = 0; i < cnt; i++) {
err = uprobe_register_refctr(d_real_inode(link->path.dentry),
uprobes[i].offset,
- ref_ctr_offsets ? ref_ctr_offsets[i] : 0,
+ uprobes[i].ref_ctr_offset,
&uprobes[i].consumer);
if (err) {
bpf_uprobe_unregister(&path, uprobes, i);
@@ -3299,11 +3293,9 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
if (err)
goto error_free;
- kvfree(ref_ctr_offsets);
return bpf_link_settle(&link_primer);
error_free:
- kvfree(ref_ctr_offsets);
kvfree(uprobes);
kfree(link);
if (task)
