Commit 4930b7f5 authored by Jiri Olsa's avatar Jiri Olsa Committed by Andrii Nakryiko
Browse files

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: default avatarJiri Olsa <jolsa@kernel.org>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Acked-by: default avatarSong Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20231125193130.834322-3-jolsa@kernel.org
parent 48f0dfd8

kernel/trace/bpf_trace.c

+3 −11
Original line number Diff line number Diff line
@@ -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)