1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  Copyright (C) 1991, 1992  Linus Torvalds
4  *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
5  */
6 
7 #ifndef _ASM_X86_STACKTRACE_H
8 #define _ASM_X86_STACKTRACE_H
9 
10 #include <linux/uaccess.h>
11 #include <linux/ptrace.h>
12 
13 #include <asm/cpu_entry_area.h>
14 #include <asm/switch_to.h>
15 
16 enum stack_type {
17 	STACK_TYPE_UNKNOWN,
18 	STACK_TYPE_TASK,
19 	STACK_TYPE_IRQ,
20 	STACK_TYPE_SOFTIRQ,
21 	STACK_TYPE_ENTRY,
22 	STACK_TYPE_EXCEPTION,
23 	STACK_TYPE_EXCEPTION_LAST = STACK_TYPE_EXCEPTION + N_EXCEPTION_STACKS-1,
24 };
25 
26 struct stack_info {
27 	enum stack_type type;
28 	unsigned long *begin, *end, *next_sp;
29 };
30 
31 bool in_task_stack(unsigned long *stack, struct task_struct *task,
32 		   struct stack_info *info);
33 
34 bool in_entry_stack(unsigned long *stack, struct stack_info *info);
35 
36 int get_stack_info(unsigned long *stack, struct task_struct *task,
37 		   struct stack_info *info, unsigned long *visit_mask);
38 bool get_stack_info_noinstr(unsigned long *stack, struct task_struct *task,
39 			    struct stack_info *info);
40 
41 static __always_inline
get_stack_guard_info(unsigned long * stack,struct stack_info * info)42 bool get_stack_guard_info(unsigned long *stack, struct stack_info *info)
43 {
44 	/* make sure it's not in the stack proper */
45 	if (get_stack_info_noinstr(stack, current, info))
46 		return false;
47 	/* but if it is in the page below it, we hit a guard */
48 	return get_stack_info_noinstr((void *)stack + PAGE_SIZE, current, info);
49 }
50 
51 const char *stack_type_name(enum stack_type type);
52 
on_stack(struct stack_info * info,void * addr,size_t len)53 static inline bool on_stack(struct stack_info *info, void *addr, size_t len)
54 {
55 	void *begin = info->begin;
56 	void *end   = info->end;
57 
58 	return (info->type != STACK_TYPE_UNKNOWN &&
59 		addr >= begin && addr < end &&
60 		addr + len > begin && addr + len <= end);
61 }
62 
63 #ifdef CONFIG_X86_32
64 #define STACKSLOTS_PER_LINE 8
65 #else
66 #define STACKSLOTS_PER_LINE 4
67 #endif
68 
69 #ifdef CONFIG_FRAME_POINTER
70 static inline unsigned long *
get_frame_pointer(struct task_struct * task,struct pt_regs * regs)71 get_frame_pointer(struct task_struct *task, struct pt_regs *regs)
72 {
73 	if (regs)
74 		return (unsigned long *)regs->bp;
75 
76 	if (task == current)
77 		return __builtin_frame_address(0);
78 
79 	return &((struct inactive_task_frame *)task->thread.sp)->bp;
80 }
81 #else
82 static inline unsigned long *
get_frame_pointer(struct task_struct * task,struct pt_regs * regs)83 get_frame_pointer(struct task_struct *task, struct pt_regs *regs)
84 {
85 	return NULL;
86 }
87 #endif /* CONFIG_FRAME_POINTER */
88 
89 static inline unsigned long *
get_stack_pointer(struct task_struct * task,struct pt_regs * regs)90 get_stack_pointer(struct task_struct *task, struct pt_regs *regs)
91 {
92 	if (regs)
93 		return (unsigned long *)regs->sp;
94 
95 	if (task == current)
96 		return __builtin_frame_address(0);
97 
98 	return (unsigned long *)task->thread.sp;
99 }
100 
101 /* The form of the top of the frame on the stack */
102 struct stack_frame {
103 	struct stack_frame *next_frame;
104 	unsigned long return_address;
105 };
106 
107 struct stack_frame_ia32 {
108     u32 next_frame;
109     u32 return_address;
110 };
111 
112 void show_opcodes(struct pt_regs *regs, const char *loglvl);
113 void show_ip(struct pt_regs *regs, const char *loglvl);
114 #endif /* _ASM_X86_STACKTRACE_H */
115