| 1 | #ifndef _ASM_X86_PTRACE_H |
| 2 | #define _ASM_X86_PTRACE_H |
| 3 | |
| 4 | #include <asm/segment.h> |
| 5 | #include <asm/page_types.h> |
| 6 | #include <uapi/asm/ptrace.h> |
| 7 | |
| 8 | #ifndef __ASSEMBLY__ |
| 9 | #ifdef __i386__ |
| 10 | |
| 11 | struct pt_regs { |
| 12 | unsigned long bx; |
| 13 | unsigned long cx; |
| 14 | unsigned long dx; |
| 15 | unsigned long si; |
| 16 | unsigned long di; |
| 17 | unsigned long bp; |
| 18 | unsigned long ax; |
| 19 | unsigned long ds; |
| 20 | unsigned long es; |
| 21 | unsigned long fs; |
| 22 | unsigned long gs; |
| 23 | unsigned long orig_ax; |
| 24 | unsigned long ip; |
| 25 | unsigned long cs; |
| 26 | unsigned long flags; |
| 27 | unsigned long sp; |
| 28 | unsigned long ss; |
| 29 | }; |
| 30 | |
| 31 | #else /* __i386__ */ |
| 32 | |
| 33 | struct pt_regs { |
| 34 | /* |
| 35 | * C ABI says these regs are callee-preserved. They aren't saved on kernel entry |
| 36 | * unless syscall needs a complete, fully filled "struct pt_regs". |
| 37 | */ |
| 38 | unsigned long r15; |
| 39 | unsigned long r14; |
| 40 | unsigned long r13; |
| 41 | unsigned long r12; |
| 42 | unsigned long bp; |
| 43 | unsigned long bx; |
| 44 | /* These regs are callee-clobbered. Always saved on kernel entry. */ |
| 45 | unsigned long r11; |
| 46 | unsigned long r10; |
| 47 | unsigned long r9; |
| 48 | unsigned long r8; |
| 49 | unsigned long ax; |
| 50 | unsigned long cx; |
| 51 | unsigned long dx; |
| 52 | unsigned long si; |
| 53 | unsigned long di; |
| 54 | /* |
| 55 | * On syscall entry, this is syscall#. On CPU exception, this is error code. |
| 56 | * On hw interrupt, it's IRQ number: |
| 57 | */ |
| 58 | unsigned long orig_ax; |
| 59 | /* Return frame for iretq */ |
| 60 | unsigned long ip; |
| 61 | unsigned long cs; |
| 62 | unsigned long flags; |
| 63 | unsigned long sp; |
| 64 | unsigned long ss; |
| 65 | /* top of stack page */ |
| 66 | }; |
| 67 | |
| 68 | #endif /* !__i386__ */ |
| 69 | |
| 70 | #ifdef CONFIG_PARAVIRT |
| 71 | #include <asm/paravirt_types.h> |
| 72 | #endif |
| 73 | |
| 74 | struct cpuinfo_x86; |
| 75 | struct task_struct; |
| 76 | |
| 77 | extern unsigned long profile_pc(struct pt_regs *regs); |
| 78 | #define profile_pc profile_pc |
| 79 | |
| 80 | extern unsigned long |
| 81 | convert_ip_to_linear(struct task_struct *child, struct pt_regs *regs); |
| 82 | extern void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, |
| 83 | int error_code, int si_code); |
| 84 | |
| 85 | |
| 86 | extern unsigned long syscall_trace_enter_phase1(struct pt_regs *, u32 arch); |
| 87 | extern long syscall_trace_enter_phase2(struct pt_regs *, u32 arch, |
| 88 | unsigned long phase1_result); |
| 89 | |
| 90 | extern long syscall_trace_enter(struct pt_regs *); |
| 91 | extern void syscall_trace_leave(struct pt_regs *); |
| 92 | |
| 93 | static inline unsigned long regs_return_value(struct pt_regs *regs) |
| 94 | { |
| 95 | return regs->ax; |
| 96 | } |
| 97 | |
| 98 | /* |
| 99 | * user_mode_vm(regs) determines whether a register set came from user mode. |
| 100 | * This is true if V8086 mode was enabled OR if the register set was from |
| 101 | * protected mode with RPL-3 CS value. This tricky test checks that with |
| 102 | * one comparison. Many places in the kernel can bypass this full check |
| 103 | * if they have already ruled out V8086 mode, so user_mode(regs) can be used. |
| 104 | */ |
| 105 | static inline int user_mode(struct pt_regs *regs) |
| 106 | { |
| 107 | #ifdef CONFIG_X86_32 |
| 108 | return (regs->cs & SEGMENT_RPL_MASK) == USER_RPL; |
| 109 | #else |
| 110 | return !!(regs->cs & 3); |
| 111 | #endif |
| 112 | } |
| 113 | |
| 114 | static inline int user_mode_vm(struct pt_regs *regs) |
| 115 | { |
| 116 | #ifdef CONFIG_X86_32 |
| 117 | return ((regs->cs & SEGMENT_RPL_MASK) | (regs->flags & X86_VM_MASK)) >= |
| 118 | USER_RPL; |
| 119 | #else |
| 120 | return user_mode(regs); |
| 121 | #endif |
| 122 | } |
| 123 | |
| 124 | /* |
| 125 | * This is the fastest way to check whether regs come from user space. |
| 126 | * It is unsafe if regs might come from vm86 mode, though -- in vm86 |
| 127 | * mode, all bits of CS and SS are completely under the user's control. |
| 128 | * The CPU considers vm86 mode to be CPL 3 regardless of CS and SS. |
| 129 | * |
| 130 | * Do NOT use this function unless you have already ruled out the |
| 131 | * possibility that regs came from vm86 mode. |
| 132 | * |
| 133 | * We check for RPL != 0 instead of RPL == 3 because we don't use rings |
| 134 | * 1 or 2 and this is more efficient. |
| 135 | */ |
| 136 | static inline int user_mode_ignore_vm86(struct pt_regs *regs) |
| 137 | { |
| 138 | return (regs->cs & SEGMENT_RPL_MASK) != 0; |
| 139 | } |
| 140 | |
| 141 | static inline int v8086_mode(struct pt_regs *regs) |
| 142 | { |
| 143 | #ifdef CONFIG_X86_32 |
| 144 | return (regs->flags & X86_VM_MASK); |
| 145 | #else |
| 146 | return 0; /* No V86 mode support in long mode */ |
| 147 | #endif |
| 148 | } |
| 149 | |
| 150 | #ifdef CONFIG_X86_64 |
| 151 | static inline bool user_64bit_mode(struct pt_regs *regs) |
| 152 | { |
| 153 | #ifndef CONFIG_PARAVIRT |
| 154 | /* |
| 155 | * On non-paravirt systems, this is the only long mode CPL 3 |
| 156 | * selector. We do not allow long mode selectors in the LDT. |
| 157 | */ |
| 158 | return regs->cs == __USER_CS; |
| 159 | #else |
| 160 | /* Headers are too twisted for this to go in paravirt.h. */ |
| 161 | return regs->cs == __USER_CS || regs->cs == pv_info.extra_user_64bit_cs; |
| 162 | #endif |
| 163 | } |
| 164 | |
| 165 | #define current_user_stack_pointer() current_pt_regs()->sp |
| 166 | #define compat_user_stack_pointer() current_pt_regs()->sp |
| 167 | #endif |
| 168 | |
| 169 | #ifdef CONFIG_X86_32 |
| 170 | extern unsigned long kernel_stack_pointer(struct pt_regs *regs); |
| 171 | #else |
| 172 | static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) |
| 173 | { |
| 174 | return regs->sp; |
| 175 | } |
| 176 | #endif |
| 177 | |
| 178 | #define GET_IP(regs) ((regs)->ip) |
| 179 | #define GET_FP(regs) ((regs)->bp) |
| 180 | #define GET_USP(regs) ((regs)->sp) |
| 181 | |
| 182 | #include <asm-generic/ptrace.h> |
| 183 | |
| 184 | /* Query offset/name of register from its name/offset */ |
| 185 | extern int regs_query_register_offset(const char *name); |
| 186 | extern const char *regs_query_register_name(unsigned int offset); |
| 187 | #define MAX_REG_OFFSET (offsetof(struct pt_regs, ss)) |
| 188 | |
| 189 | /** |
| 190 | * regs_get_register() - get register value from its offset |
| 191 | * @regs: pt_regs from which register value is gotten. |
| 192 | * @offset: offset number of the register. |
| 193 | * |
| 194 | * regs_get_register returns the value of a register. The @offset is the |
| 195 | * offset of the register in struct pt_regs address which specified by @regs. |
| 196 | * If @offset is bigger than MAX_REG_OFFSET, this returns 0. |
| 197 | */ |
| 198 | static inline unsigned long regs_get_register(struct pt_regs *regs, |
| 199 | unsigned int offset) |
| 200 | { |
| 201 | if (unlikely(offset > MAX_REG_OFFSET)) |
| 202 | return 0; |
| 203 | #ifdef CONFIG_X86_32 |
| 204 | /* |
| 205 | * Traps from the kernel do not save sp and ss. |
| 206 | * Use the helper function to retrieve sp. |
| 207 | */ |
| 208 | if (offset == offsetof(struct pt_regs, sp) && |
| 209 | regs->cs == __KERNEL_CS) |
| 210 | return kernel_stack_pointer(regs); |
| 211 | #endif |
| 212 | return *(unsigned long *)((unsigned long)regs + offset); |
| 213 | } |
| 214 | |
| 215 | /** |
| 216 | * regs_within_kernel_stack() - check the address in the stack |
| 217 | * @regs: pt_regs which contains kernel stack pointer. |
| 218 | * @addr: address which is checked. |
| 219 | * |
| 220 | * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). |
| 221 | * If @addr is within the kernel stack, it returns true. If not, returns false. |
| 222 | */ |
| 223 | static inline int regs_within_kernel_stack(struct pt_regs *regs, |
| 224 | unsigned long addr) |
| 225 | { |
| 226 | return ((addr & ~(THREAD_SIZE - 1)) == |
| 227 | (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))); |
| 228 | } |
| 229 | |
| 230 | /** |
| 231 | * regs_get_kernel_stack_nth() - get Nth entry of the stack |
| 232 | * @regs: pt_regs which contains kernel stack pointer. |
| 233 | * @n: stack entry number. |
| 234 | * |
| 235 | * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which |
| 236 | * is specified by @regs. If the @n th entry is NOT in the kernel stack, |
| 237 | * this returns 0. |
| 238 | */ |
| 239 | static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, |
| 240 | unsigned int n) |
| 241 | { |
| 242 | unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); |
| 243 | addr += n; |
| 244 | if (regs_within_kernel_stack(regs, (unsigned long)addr)) |
| 245 | return *addr; |
| 246 | else |
| 247 | return 0; |
| 248 | } |
| 249 | |
| 250 | #define arch_has_single_step() (1) |
| 251 | #ifdef CONFIG_X86_DEBUGCTLMSR |
| 252 | #define arch_has_block_step() (1) |
| 253 | #else |
| 254 | #define arch_has_block_step() (boot_cpu_data.x86 >= 6) |
| 255 | #endif |
| 256 | |
| 257 | #define ARCH_HAS_USER_SINGLE_STEP_INFO |
| 258 | |
| 259 | /* |
| 260 | * When hitting ptrace_stop(), we cannot return using SYSRET because |
| 261 | * that does not restore the full CPU state, only a minimal set. The |
| 262 | * ptracer can change arbitrary register values, which is usually okay |
| 263 | * because the usual ptrace stops run off the signal delivery path which |
| 264 | * forces IRET; however, ptrace_event() stops happen in arbitrary places |
| 265 | * in the kernel and don't force IRET path. |
| 266 | * |
| 267 | * So force IRET path after a ptrace stop. |
| 268 | */ |
| 269 | #define arch_ptrace_stop_needed(code, info) \ |
| 270 | ({ \ |
| 271 | force_iret(); \ |
| 272 | false; \ |
| 273 | }) |
| 274 | |
| 275 | struct user_desc; |
| 276 | extern int do_get_thread_area(struct task_struct *p, int idx, |
| 277 | struct user_desc __user *info); |
| 278 | extern int do_set_thread_area(struct task_struct *p, int idx, |
| 279 | struct user_desc __user *info, int can_allocate); |
| 280 | |
| 281 | #endif /* !__ASSEMBLY__ */ |
| 282 | #endif /* _ASM_X86_PTRACE_H */ |