linux-user: Don't allow guest to block SIGSEGV
[qemu.git] / linux-user / qemu.h
1 #ifndef QEMU_H
2 #define QEMU_H
3
4 #include <signal.h>
5 #include <string.h>
6
7 #include "cpu.h"
8
9 #undef DEBUG_REMAP
10 #ifdef DEBUG_REMAP
11 #include <stdlib.h>
12 #endif /* DEBUG_REMAP */
13
14 #include "exec/user/abitypes.h"
15
16 #include "exec/user/thunk.h"
17 #include "syscall_defs.h"
18 #include "syscall.h"
19 #include "exec/gdbstub.h"
20 #include "qemu/queue.h"
21
22 #define THREAD __thread
23
24 /* This struct is used to hold certain information about the image.
25 * Basically, it replicates in user space what would be certain
26 * task_struct fields in the kernel
27 */
28 struct image_info {
29 abi_ulong load_bias;
30 abi_ulong load_addr;
31 abi_ulong start_code;
32 abi_ulong end_code;
33 abi_ulong start_data;
34 abi_ulong end_data;
35 abi_ulong start_brk;
36 abi_ulong brk;
37 abi_ulong start_mmap;
38 abi_ulong mmap;
39 abi_ulong rss;
40 abi_ulong start_stack;
41 abi_ulong stack_limit;
42 abi_ulong entry;
43 abi_ulong code_offset;
44 abi_ulong data_offset;
45 abi_ulong saved_auxv;
46 abi_ulong auxv_len;
47 abi_ulong arg_start;
48 abi_ulong arg_end;
49 uint32_t elf_flags;
50 int personality;
51 #ifdef CONFIG_USE_FDPIC
52 abi_ulong loadmap_addr;
53 uint16_t nsegs;
54 void *loadsegs;
55 abi_ulong pt_dynamic_addr;
56 struct image_info *other_info;
57 #endif
58 };
59
60 #ifdef TARGET_I386
61 /* Information about the current linux thread */
62 struct vm86_saved_state {
63 uint32_t eax; /* return code */
64 uint32_t ebx;
65 uint32_t ecx;
66 uint32_t edx;
67 uint32_t esi;
68 uint32_t edi;
69 uint32_t ebp;
70 uint32_t esp;
71 uint32_t eflags;
72 uint32_t eip;
73 uint16_t cs, ss, ds, es, fs, gs;
74 };
75 #endif
76
77 #if defined(TARGET_ARM) && defined(TARGET_ABI32)
78 /* FPU emulator */
79 #include "nwfpe/fpa11.h"
80 #endif
81
82 #define MAX_SIGQUEUE_SIZE 1024
83
84 struct sigqueue {
85 struct sigqueue *next;
86 target_siginfo_t info;
87 };
88
89 struct emulated_sigtable {
90 int pending; /* true if signal is pending */
91 struct sigqueue *first;
92 struct sigqueue info; /* in order to always have memory for the
93 first signal, we put it here */
94 };
95
96 /* NOTE: we force a big alignment so that the stack stored after is
97 aligned too */
98 typedef struct TaskState {
99 pid_t ts_tid; /* tid (or pid) of this task */
100 #ifdef TARGET_ARM
101 # ifdef TARGET_ABI32
102 /* FPA state */
103 FPA11 fpa;
104 # endif
105 int swi_errno;
106 #endif
107 #ifdef TARGET_UNICORE32
108 int swi_errno;
109 #endif
110 #if defined(TARGET_I386) && !defined(TARGET_X86_64)
111 abi_ulong target_v86;
112 struct vm86_saved_state vm86_saved_regs;
113 struct target_vm86plus_struct vm86plus;
114 uint32_t v86flags;
115 uint32_t v86mask;
116 #endif
117 abi_ulong child_tidptr;
118 #ifdef TARGET_M68K
119 int sim_syscalls;
120 abi_ulong tp_value;
121 #endif
122 #if defined(TARGET_ARM) || defined(TARGET_M68K) || defined(TARGET_UNICORE32)
123 /* Extra fields for semihosted binaries. */
124 uint32_t heap_base;
125 uint32_t heap_limit;
126 #endif
127 uint32_t stack_base;
128 int used; /* non zero if used */
129 bool sigsegv_blocked; /* SIGSEGV blocked by guest */
130 struct image_info *info;
131 struct linux_binprm *bprm;
132
133 struct emulated_sigtable sigtab[TARGET_NSIG];
134 struct sigqueue sigqueue_table[MAX_SIGQUEUE_SIZE]; /* siginfo queue */
135 struct sigqueue *first_free; /* first free siginfo queue entry */
136 int signal_pending; /* non zero if a signal may be pending */
137 } __attribute__((aligned(16))) TaskState;
138
139 extern char *exec_path;
140 void init_task_state(TaskState *ts);
141 void task_settid(TaskState *);
142 void stop_all_tasks(void);
143 extern const char *qemu_uname_release;
144 extern unsigned long mmap_min_addr;
145
146 /* ??? See if we can avoid exposing so much of the loader internals. */
147 /*
148 * MAX_ARG_PAGES defines the number of pages allocated for arguments
149 * and envelope for the new program. 32 should suffice, this gives
150 * a maximum env+arg of 128kB w/4KB pages!
151 */
152 #define MAX_ARG_PAGES 33
153
154 /* Read a good amount of data initially, to hopefully get all the
155 program headers loaded. */
156 #define BPRM_BUF_SIZE 1024
157
158 /*
159 * This structure is used to hold the arguments that are
160 * used when loading binaries.
161 */
162 struct linux_binprm {
163 char buf[BPRM_BUF_SIZE] __attribute__((aligned));
164 void *page[MAX_ARG_PAGES];
165 abi_ulong p;
166 int fd;
167 int e_uid, e_gid;
168 int argc, envc;
169 char **argv;
170 char **envp;
171 char * filename; /* Name of binary */
172 int (*core_dump)(int, const CPUArchState *); /* coredump routine */
173 };
174
175 void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
176 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
177 abi_ulong stringp, int push_ptr);
178 int loader_exec(int fdexec, const char *filename, char **argv, char **envp,
179 struct target_pt_regs * regs, struct image_info *infop,
180 struct linux_binprm *);
181
182 int load_elf_binary(struct linux_binprm *bprm, struct image_info *info);
183 int load_flt_binary(struct linux_binprm *bprm, struct image_info *info);
184
185 abi_long memcpy_to_target(abi_ulong dest, const void *src,
186 unsigned long len);
187 void target_set_brk(abi_ulong new_brk);
188 abi_long do_brk(abi_ulong new_brk);
189 void syscall_init(void);
190 abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
191 abi_long arg2, abi_long arg3, abi_long arg4,
192 abi_long arg5, abi_long arg6, abi_long arg7,
193 abi_long arg8);
194 void gemu_log(const char *fmt, ...) GCC_FMT_ATTR(1, 2);
195 extern THREAD CPUState *thread_cpu;
196 void cpu_loop(CPUArchState *env);
197 char *target_strerror(int err);
198 int get_osversion(void);
199 void init_qemu_uname_release(void);
200 void fork_start(void);
201 void fork_end(int child);
202
203 /* Creates the initial guest address space in the host memory space using
204 * the given host start address hint and size. The guest_start parameter
205 * specifies the start address of the guest space. guest_base will be the
206 * difference between the host start address computed by this function and
207 * guest_start. If fixed is specified, then the mapped address space must
208 * start at host_start. The real start address of the mapped memory space is
209 * returned or -1 if there was an error.
210 */
211 unsigned long init_guest_space(unsigned long host_start,
212 unsigned long host_size,
213 unsigned long guest_start,
214 bool fixed);
215
216 #include "qemu/log.h"
217
218 /* syscall.c */
219 int host_to_target_waitstatus(int status);
220
221 /* strace.c */
222 void print_syscall(int num,
223 abi_long arg1, abi_long arg2, abi_long arg3,
224 abi_long arg4, abi_long arg5, abi_long arg6);
225 void print_syscall_ret(int num, abi_long arg1);
226 extern int do_strace;
227
228 /* signal.c */
229 void process_pending_signals(CPUArchState *cpu_env);
230 void signal_init(void);
231 int queue_signal(CPUArchState *env, int sig, target_siginfo_t *info);
232 void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info);
233 void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo);
234 int target_to_host_signal(int sig);
235 int host_to_target_signal(int sig);
236 long do_sigreturn(CPUArchState *env);
237 long do_rt_sigreturn(CPUArchState *env);
238 abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
239 int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset);
240
241 #ifdef TARGET_I386
242 /* vm86.c */
243 void save_v86_state(CPUX86State *env);
244 void handle_vm86_trap(CPUX86State *env, int trapno);
245 void handle_vm86_fault(CPUX86State *env);
246 int do_vm86(CPUX86State *env, long subfunction, abi_ulong v86_addr);
247 #elif defined(TARGET_SPARC64)
248 void sparc64_set_context(CPUSPARCState *env);
249 void sparc64_get_context(CPUSPARCState *env);
250 #endif
251
252 /* mmap.c */
253 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
254 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
255 int flags, int fd, abi_ulong offset);
256 int target_munmap(abi_ulong start, abi_ulong len);
257 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
258 abi_ulong new_size, unsigned long flags,
259 abi_ulong new_addr);
260 int target_msync(abi_ulong start, abi_ulong len, int flags);
261 extern unsigned long last_brk;
262 extern abi_ulong mmap_next_start;
263 void mmap_lock(void);
264 void mmap_unlock(void);
265 abi_ulong mmap_find_vma(abi_ulong, abi_ulong);
266 void cpu_list_lock(void);
267 void cpu_list_unlock(void);
268 void mmap_fork_start(void);
269 void mmap_fork_end(int child);
270
271 /* main.c */
272 extern unsigned long guest_stack_size;
273
274 /* user access */
275
276 #define VERIFY_READ 0
277 #define VERIFY_WRITE 1 /* implies read access */
278
279 static inline int access_ok(int type, abi_ulong addr, abi_ulong size)
280 {
281 return page_check_range((target_ulong)addr, size,
282 (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0;
283 }
284
285 /* NOTE __get_user and __put_user use host pointers and don't check access.
286 These are usually used to access struct data members once the struct has
287 been locked - usually with lock_user_struct. */
288
289 /* Tricky points:
290 - Use __builtin_choose_expr to avoid type promotion from ?:,
291 - Invalid sizes result in a compile time error stemming from
292 the fact that abort has no parameters.
293 - It's easier to use the endian-specific unaligned load/store
294 functions than host-endian unaligned load/store plus tswapN. */
295
296 #define __put_user_e(x, hptr, e) \
297 (__builtin_choose_expr(sizeof(*(hptr)) == 1, stb_p, \
298 __builtin_choose_expr(sizeof(*(hptr)) == 2, stw_##e##_p, \
299 __builtin_choose_expr(sizeof(*(hptr)) == 4, stl_##e##_p, \
300 __builtin_choose_expr(sizeof(*(hptr)) == 8, stq_##e##_p, abort)))) \
301 ((hptr), (x)), 0)
302
303 #define __get_user_e(x, hptr, e) \
304 ((x) = (typeof(*hptr))( \
305 __builtin_choose_expr(sizeof(*(hptr)) == 1, ldub_p, \
306 __builtin_choose_expr(sizeof(*(hptr)) == 2, lduw_##e##_p, \
307 __builtin_choose_expr(sizeof(*(hptr)) == 4, ldl_##e##_p, \
308 __builtin_choose_expr(sizeof(*(hptr)) == 8, ldq_##e##_p, abort)))) \
309 (hptr)), 0)
310
311 #ifdef TARGET_WORDS_BIGENDIAN
312 # define __put_user(x, hptr) __put_user_e(x, hptr, be)
313 # define __get_user(x, hptr) __get_user_e(x, hptr, be)
314 #else
315 # define __put_user(x, hptr) __put_user_e(x, hptr, le)
316 # define __get_user(x, hptr) __get_user_e(x, hptr, le)
317 #endif
318
319 /* put_user()/get_user() take a guest address and check access */
320 /* These are usually used to access an atomic data type, such as an int,
321 * that has been passed by address. These internally perform locking
322 * and unlocking on the data type.
323 */
324 #define put_user(x, gaddr, target_type) \
325 ({ \
326 abi_ulong __gaddr = (gaddr); \
327 target_type *__hptr; \
328 abi_long __ret; \
329 if ((__hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0))) { \
330 __ret = __put_user((x), __hptr); \
331 unlock_user(__hptr, __gaddr, sizeof(target_type)); \
332 } else \
333 __ret = -TARGET_EFAULT; \
334 __ret; \
335 })
336
337 #define get_user(x, gaddr, target_type) \
338 ({ \
339 abi_ulong __gaddr = (gaddr); \
340 target_type *__hptr; \
341 abi_long __ret; \
342 if ((__hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1))) { \
343 __ret = __get_user((x), __hptr); \
344 unlock_user(__hptr, __gaddr, 0); \
345 } else { \
346 /* avoid warning */ \
347 (x) = 0; \
348 __ret = -TARGET_EFAULT; \
349 } \
350 __ret; \
351 })
352
353 #define put_user_ual(x, gaddr) put_user((x), (gaddr), abi_ulong)
354 #define put_user_sal(x, gaddr) put_user((x), (gaddr), abi_long)
355 #define put_user_u64(x, gaddr) put_user((x), (gaddr), uint64_t)
356 #define put_user_s64(x, gaddr) put_user((x), (gaddr), int64_t)
357 #define put_user_u32(x, gaddr) put_user((x), (gaddr), uint32_t)
358 #define put_user_s32(x, gaddr) put_user((x), (gaddr), int32_t)
359 #define put_user_u16(x, gaddr) put_user((x), (gaddr), uint16_t)
360 #define put_user_s16(x, gaddr) put_user((x), (gaddr), int16_t)
361 #define put_user_u8(x, gaddr) put_user((x), (gaddr), uint8_t)
362 #define put_user_s8(x, gaddr) put_user((x), (gaddr), int8_t)
363
364 #define get_user_ual(x, gaddr) get_user((x), (gaddr), abi_ulong)
365 #define get_user_sal(x, gaddr) get_user((x), (gaddr), abi_long)
366 #define get_user_u64(x, gaddr) get_user((x), (gaddr), uint64_t)
367 #define get_user_s64(x, gaddr) get_user((x), (gaddr), int64_t)
368 #define get_user_u32(x, gaddr) get_user((x), (gaddr), uint32_t)
369 #define get_user_s32(x, gaddr) get_user((x), (gaddr), int32_t)
370 #define get_user_u16(x, gaddr) get_user((x), (gaddr), uint16_t)
371 #define get_user_s16(x, gaddr) get_user((x), (gaddr), int16_t)
372 #define get_user_u8(x, gaddr) get_user((x), (gaddr), uint8_t)
373 #define get_user_s8(x, gaddr) get_user((x), (gaddr), int8_t)
374
375 /* copy_from_user() and copy_to_user() are usually used to copy data
376 * buffers between the target and host. These internally perform
377 * locking/unlocking of the memory.
378 */
379 abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len);
380 abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len);
381
382 /* Functions for accessing guest memory. The tget and tput functions
383 read/write single values, byteswapping as necessary. The lock_user function
384 gets a pointer to a contiguous area of guest memory, but does not perform
385 any byteswapping. lock_user may return either a pointer to the guest
386 memory, or a temporary buffer. */
387
388 /* Lock an area of guest memory into the host. If copy is true then the
389 host area will have the same contents as the guest. */
390 static inline void *lock_user(int type, abi_ulong guest_addr, long len, int copy)
391 {
392 if (!access_ok(type, guest_addr, len))
393 return NULL;
394 #ifdef DEBUG_REMAP
395 {
396 void *addr;
397 addr = malloc(len);
398 if (copy)
399 memcpy(addr, g2h(guest_addr), len);
400 else
401 memset(addr, 0, len);
402 return addr;
403 }
404 #else
405 return g2h(guest_addr);
406 #endif
407 }
408
409 /* Unlock an area of guest memory. The first LEN bytes must be
410 flushed back to guest memory. host_ptr = NULL is explicitly
411 allowed and does nothing. */
412 static inline void unlock_user(void *host_ptr, abi_ulong guest_addr,
413 long len)
414 {
415
416 #ifdef DEBUG_REMAP
417 if (!host_ptr)
418 return;
419 if (host_ptr == g2h(guest_addr))
420 return;
421 if (len > 0)
422 memcpy(g2h(guest_addr), host_ptr, len);
423 free(host_ptr);
424 #endif
425 }
426
427 /* Return the length of a string in target memory or -TARGET_EFAULT if
428 access error. */
429 abi_long target_strlen(abi_ulong gaddr);
430
431 /* Like lock_user but for null terminated strings. */
432 static inline void *lock_user_string(abi_ulong guest_addr)
433 {
434 abi_long len;
435 len = target_strlen(guest_addr);
436 if (len < 0)
437 return NULL;
438 return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
439 }
440
441 /* Helper macros for locking/unlocking a target struct. */
442 #define lock_user_struct(type, host_ptr, guest_addr, copy) \
443 (host_ptr = lock_user(type, guest_addr, sizeof(*host_ptr), copy))
444 #define unlock_user_struct(host_ptr, guest_addr, copy) \
445 unlock_user(host_ptr, guest_addr, (copy) ? sizeof(*host_ptr) : 0)
446
447 #include <pthread.h>
448
449 /* Include target-specific struct and function definitions;
450 * they may need access to the target-independent structures
451 * above, so include them last.
452 */
453 #include "target_cpu.h"
454 #include "target_signal.h"
455 #include "target_structs.h"
456
457 #endif /* QEMU_H */