320 lines
8.6 KiB
C
320 lines
8.6 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
|
#ifndef _ASM_X86_PTRACE_H
|
||
|
|
#define _ASM_X86_PTRACE_H
|
||
|
|
|
||
|
|
#include <asm/segment.h>
|
||
|
|
#include <asm/page_types.h>
|
||
|
|
#include <uapi/asm/ptrace.h>
|
||
|
|
|
||
|
|
#ifndef __ASSEMBLY__
|
||
|
|
#ifdef __i386__
|
||
|
|
|
||
|
|
struct pt_regs {
|
||
|
|
/*
|
||
|
|
* NB: 32-bit x86 CPUs are inconsistent as what happens in the
|
||
|
|
* following cases (where %seg represents a segment register):
|
||
|
|
*
|
||
|
|
* - pushl %seg: some do a 16-bit write and leave the high
|
||
|
|
* bits alone
|
||
|
|
* - movl %seg, [mem]: some do a 16-bit write despite the movl
|
||
|
|
* - IDT entry: some (e.g. 486) will leave the high bits of CS
|
||
|
|
* and (if applicable) SS undefined.
|
||
|
|
*
|
||
|
|
* Fortunately, x86-32 doesn't read the high bits on POP or IRET,
|
||
|
|
* so we can just treat all of the segment registers as 16-bit
|
||
|
|
* values.
|
||
|
|
*/
|
||
|
|
unsigned long bx;
|
||
|
|
unsigned long cx;
|
||
|
|
unsigned long dx;
|
||
|
|
unsigned long si;
|
||
|
|
unsigned long di;
|
||
|
|
unsigned long bp;
|
||
|
|
unsigned long ax;
|
||
|
|
unsigned short ds;
|
||
|
|
unsigned short __dsh;
|
||
|
|
unsigned short es;
|
||
|
|
unsigned short __esh;
|
||
|
|
unsigned short fs;
|
||
|
|
unsigned short __fsh;
|
||
|
|
unsigned short gs;
|
||
|
|
unsigned short __gsh;
|
||
|
|
unsigned long orig_ax;
|
||
|
|
unsigned long ip;
|
||
|
|
unsigned short cs;
|
||
|
|
unsigned short __csh;
|
||
|
|
unsigned long flags;
|
||
|
|
unsigned long sp;
|
||
|
|
unsigned short ss;
|
||
|
|
unsigned short __ssh;
|
||
|
|
};
|
||
|
|
|
||
|
|
#else /* __i386__ */
|
||
|
|
|
||
|
|
struct pt_regs {
|
||
|
|
/*
|
||
|
|
* C ABI says these regs are callee-preserved. They aren't saved on kernel entry
|
||
|
|
* unless syscall needs a complete, fully filled "struct pt_regs".
|
||
|
|
*/
|
||
|
|
unsigned long r15;
|
||
|
|
unsigned long r14;
|
||
|
|
unsigned long r13;
|
||
|
|
unsigned long r12;
|
||
|
|
unsigned long bp;
|
||
|
|
unsigned long bx;
|
||
|
|
/* These regs are callee-clobbered. Always saved on kernel entry. */
|
||
|
|
unsigned long r11;
|
||
|
|
unsigned long r10;
|
||
|
|
unsigned long r9;
|
||
|
|
unsigned long r8;
|
||
|
|
unsigned long ax;
|
||
|
|
unsigned long cx;
|
||
|
|
unsigned long dx;
|
||
|
|
unsigned long si;
|
||
|
|
unsigned long di;
|
||
|
|
/*
|
||
|
|
* On syscall entry, this is syscall#. On CPU exception, this is error code.
|
||
|
|
* On hw interrupt, it's IRQ number:
|
||
|
|
*/
|
||
|
|
unsigned long orig_ax;
|
||
|
|
/* Return frame for iretq */
|
||
|
|
unsigned long ip;
|
||
|
|
unsigned long cs;
|
||
|
|
unsigned long flags;
|
||
|
|
unsigned long sp;
|
||
|
|
unsigned long ss;
|
||
|
|
/* top of stack page */
|
||
|
|
};
|
||
|
|
|
||
|
|
#endif /* !__i386__ */
|
||
|
|
|
||
|
|
#ifdef CONFIG_PARAVIRT
|
||
|
|
#include <asm/paravirt_types.h>
|
||
|
|
#endif
|
||
|
|
|
||
|
|
struct cpuinfo_x86;
|
||
|
|
struct task_struct;
|
||
|
|
|
||
|
|
extern unsigned long profile_pc(struct pt_regs *regs);
|
||
|
|
#define profile_pc profile_pc
|
||
|
|
|
||
|
|
extern unsigned long
|
||
|
|
convert_ip_to_linear(struct task_struct *child, struct pt_regs *regs);
|
||
|
|
extern void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
|
||
|
|
int error_code, int si_code);
|
||
|
|
|
||
|
|
|
||
|
|
static inline unsigned long regs_return_value(struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
return regs->ax;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc)
|
||
|
|
{
|
||
|
|
regs->ax = rc;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* user_mode(regs) determines whether a register set came from user
|
||
|
|
* mode. On x86_32, this is true if V8086 mode was enabled OR if the
|
||
|
|
* register set was from protected mode with RPL-3 CS value. This
|
||
|
|
* tricky test checks that with one comparison.
|
||
|
|
*
|
||
|
|
* On x86_64, vm86 mode is mercifully nonexistent, and we don't need
|
||
|
|
* the extra check.
|
||
|
|
*/
|
||
|
|
static inline int user_mode(struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
#ifdef CONFIG_X86_32
|
||
|
|
return ((regs->cs & SEGMENT_RPL_MASK) | (regs->flags & X86_VM_MASK)) >= USER_RPL;
|
||
|
|
#else
|
||
|
|
return !!(regs->cs & 3);
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int v8086_mode(struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
#ifdef CONFIG_X86_32
|
||
|
|
return (regs->flags & X86_VM_MASK);
|
||
|
|
#else
|
||
|
|
return 0; /* No V86 mode support in long mode */
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline bool user_64bit_mode(struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
#ifdef CONFIG_X86_64
|
||
|
|
#ifndef CONFIG_PARAVIRT
|
||
|
|
/*
|
||
|
|
* On non-paravirt systems, this is the only long mode CPL 3
|
||
|
|
* selector. We do not allow long mode selectors in the LDT.
|
||
|
|
*/
|
||
|
|
return regs->cs == __USER_CS;
|
||
|
|
#else
|
||
|
|
/* Headers are too twisted for this to go in paravirt.h. */
|
||
|
|
return regs->cs == __USER_CS || regs->cs == pv_info.extra_user_64bit_cs;
|
||
|
|
#endif
|
||
|
|
#else /* !CONFIG_X86_64 */
|
||
|
|
return false;
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifdef CONFIG_X86_64
|
||
|
|
#define current_user_stack_pointer() current_pt_regs()->sp
|
||
|
|
#define compat_user_stack_pointer() current_pt_regs()->sp
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifdef CONFIG_X86_32
|
||
|
|
extern unsigned long kernel_stack_pointer(struct pt_regs *regs);
|
||
|
|
#else
|
||
|
|
static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
return regs->sp;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#define GET_IP(regs) ((regs)->ip)
|
||
|
|
#define GET_FP(regs) ((regs)->bp)
|
||
|
|
#define GET_USP(regs) ((regs)->sp)
|
||
|
|
|
||
|
|
#include <asm-generic/ptrace.h>
|
||
|
|
|
||
|
|
/* Query offset/name of register from its name/offset */
|
||
|
|
extern int regs_query_register_offset(const char *name);
|
||
|
|
extern const char *regs_query_register_name(unsigned int offset);
|
||
|
|
#define MAX_REG_OFFSET (offsetof(struct pt_regs, ss))
|
||
|
|
|
||
|
|
/**
|
||
|
|
* regs_get_register() - get register value from its offset
|
||
|
|
* @regs: pt_regs from which register value is gotten.
|
||
|
|
* @offset: offset number of the register.
|
||
|
|
*
|
||
|
|
* regs_get_register returns the value of a register. The @offset is the
|
||
|
|
* offset of the register in struct pt_regs address which specified by @regs.
|
||
|
|
* If @offset is bigger than MAX_REG_OFFSET, this returns 0.
|
||
|
|
*/
|
||
|
|
static inline unsigned long regs_get_register(struct pt_regs *regs,
|
||
|
|
unsigned int offset)
|
||
|
|
{
|
||
|
|
if (unlikely(offset > MAX_REG_OFFSET))
|
||
|
|
return 0;
|
||
|
|
#ifdef CONFIG_X86_32
|
||
|
|
/*
|
||
|
|
* Traps from the kernel do not save sp and ss.
|
||
|
|
* Use the helper function to retrieve sp.
|
||
|
|
*/
|
||
|
|
if (offset == offsetof(struct pt_regs, sp) &&
|
||
|
|
regs->cs == __KERNEL_CS)
|
||
|
|
return kernel_stack_pointer(regs);
|
||
|
|
|
||
|
|
/* The selector fields are 16-bit. */
|
||
|
|
if (offset == offsetof(struct pt_regs, cs) ||
|
||
|
|
offset == offsetof(struct pt_regs, ss) ||
|
||
|
|
offset == offsetof(struct pt_regs, ds) ||
|
||
|
|
offset == offsetof(struct pt_regs, es) ||
|
||
|
|
offset == offsetof(struct pt_regs, fs) ||
|
||
|
|
offset == offsetof(struct pt_regs, gs)) {
|
||
|
|
return *(u16 *)((unsigned long)regs + offset);
|
||
|
|
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
return *(unsigned long *)((unsigned long)regs + offset);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* regs_within_kernel_stack() - check the address in the stack
|
||
|
|
* @regs: pt_regs which contains kernel stack pointer.
|
||
|
|
* @addr: address which is checked.
|
||
|
|
*
|
||
|
|
* regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
|
||
|
|
* If @addr is within the kernel stack, it returns true. If not, returns false.
|
||
|
|
*/
|
||
|
|
static inline int regs_within_kernel_stack(struct pt_regs *regs,
|
||
|
|
unsigned long addr)
|
||
|
|
{
|
||
|
|
return ((addr & ~(THREAD_SIZE - 1)) ==
|
||
|
|
(kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* regs_get_kernel_stack_nth_addr() - get the address of the Nth entry on stack
|
||
|
|
* @regs: pt_regs which contains kernel stack pointer.
|
||
|
|
* @n: stack entry number.
|
||
|
|
*
|
||
|
|
* regs_get_kernel_stack_nth() returns the address of the @n th entry of the
|
||
|
|
* kernel stack which is specified by @regs. If the @n th entry is NOT in
|
||
|
|
* the kernel stack, this returns NULL.
|
||
|
|
*/
|
||
|
|
static inline unsigned long *regs_get_kernel_stack_nth_addr(struct pt_regs *regs, unsigned int n)
|
||
|
|
{
|
||
|
|
unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
|
||
|
|
|
||
|
|
addr += n;
|
||
|
|
if (regs_within_kernel_stack(regs, (unsigned long)addr))
|
||
|
|
return addr;
|
||
|
|
else
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* To avoid include hell, we can't include uaccess.h */
|
||
|
|
extern long probe_kernel_read(void *dst, const void *src, size_t size);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* regs_get_kernel_stack_nth() - get Nth entry of the stack
|
||
|
|
* @regs: pt_regs which contains kernel stack pointer.
|
||
|
|
* @n: stack entry number.
|
||
|
|
*
|
||
|
|
* regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
|
||
|
|
* is specified by @regs. If the @n th entry is NOT in the kernel stack
|
||
|
|
* this returns 0.
|
||
|
|
*/
|
||
|
|
static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
|
||
|
|
unsigned int n)
|
||
|
|
{
|
||
|
|
unsigned long *addr;
|
||
|
|
unsigned long val;
|
||
|
|
long ret;
|
||
|
|
|
||
|
|
addr = regs_get_kernel_stack_nth_addr(regs, n);
|
||
|
|
if (addr) {
|
||
|
|
ret = probe_kernel_read(&val, addr, sizeof(val));
|
||
|
|
if (!ret)
|
||
|
|
return val;
|
||
|
|
}
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
#define arch_has_single_step() (1)
|
||
|
|
#ifdef CONFIG_X86_DEBUGCTLMSR
|
||
|
|
#define arch_has_block_step() (1)
|
||
|
|
#else
|
||
|
|
#define arch_has_block_step() (boot_cpu_data.x86 >= 6)
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#define ARCH_HAS_USER_SINGLE_STEP_INFO
|
||
|
|
|
||
|
|
/*
|
||
|
|
* When hitting ptrace_stop(), we cannot return using SYSRET because
|
||
|
|
* that does not restore the full CPU state, only a minimal set. The
|
||
|
|
* ptracer can change arbitrary register values, which is usually okay
|
||
|
|
* because the usual ptrace stops run off the signal delivery path which
|
||
|
|
* forces IRET; however, ptrace_event() stops happen in arbitrary places
|
||
|
|
* in the kernel and don't force IRET path.
|
||
|
|
*
|
||
|
|
* So force IRET path after a ptrace stop.
|
||
|
|
*/
|
||
|
|
#define arch_ptrace_stop_needed(code, info) \
|
||
|
|
({ \
|
||
|
|
force_iret(); \
|
||
|
|
false; \
|
||
|
|
})
|
||
|
|
|
||
|
|
struct user_desc;
|
||
|
|
extern int do_get_thread_area(struct task_struct *p, int idx,
|
||
|
|
struct user_desc __user *info);
|
||
|
|
extern int do_set_thread_area(struct task_struct *p, int idx,
|
||
|
|
struct user_desc __user *info, int can_allocate);
|
||
|
|
|
||
|
|
#endif /* !__ASSEMBLY__ */
|
||
|
|
#endif /* _ASM_X86_PTRACE_H */
|