1 // SPDX-License-Identifier: GPL-2.0 1
2
3 #include <linux/kprobes.h>
4
5 /* Ftrace callback handler for kprobes -- call
6 void kprobe_ftrace_handler(unsigned long ip, u
7 struct ftrace_ops *
8 {
9 int bit;
10 bool lr_saver = false;
11 struct kprobe *p;
12 struct kprobe_ctlblk *kcb;
13 struct pt_regs *regs;
14
15 if (unlikely(kprobe_ftrace_disabled))
16 return;
17
18 bit = ftrace_test_recursion_trylock(ip
19 if (bit < 0)
20 return;
21
22 regs = ftrace_get_regs(fregs);
23 p = get_kprobe((kprobe_opcode_t *)ip);
24 if (!p) {
25 p = get_kprobe((kprobe_opcode_
26 if (unlikely(!p) || kprobe_dis
27 goto out;
28 lr_saver = true;
29 }
30
31 kcb = get_kprobe_ctlblk();
32 if (kprobe_running()) {
33 kprobes_inc_nmissed_count(p);
34 } else {
35 unsigned long orig_ip = instru
36
37 if (lr_saver)
38 ip -= MCOUNT_INSN_SIZE
39 instruction_pointer_set(regs,
40 __this_cpu_write(current_kprob
41 kcb->kprobe_status = KPROBE_HI
42 if (!p->pre_handler || !p->pre
43 /*
44 * Emulate singlestep
45 * as if there is a no
46 */
47 instruction_pointer_se
48 (unsigned long
49 if (unlikely(p->post_h
50 kcb->kprobe_st
51 p->post_handle
52 }
53 instruction_pointer_se
54 }
55 /*
56 * If pre_handler returns !0,
57 * skip emulating post_handler
58 */
59 __this_cpu_write(current_kprob
60 }
61 out:
62 ftrace_test_recursion_unlock(bit);
63 }
64 NOKPROBE_SYMBOL(kprobe_ftrace_handler);
65
66 int arch_prepare_kprobe_ftrace(struct kprobe *
67 {
68 p->ainsn.api.insn = NULL;
69 return 0;
70 }
71
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.