Commit | Line | Data |
---|---|---|
abaf6977 | 1 | /* |
ba180fd4 | 2 | * Copyright (C) 2002- 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
abaf6977 GS |
3 | * Licensed under the GPL |
4 | */ | |
5 | ||
6 | #include <stdlib.h> | |
abaf6977 | 7 | #include <unistd.h> |
abaf6977 | 8 | #include <sched.h> |
ba180fd4 JD |
9 | #include <errno.h> |
10 | #include <string.h> | |
abaf6977 | 11 | #include <sys/mman.h> |
ba180fd4 JD |
12 | #include <sys/wait.h> |
13 | #include <asm/unistd.h> | |
37185b33 AV |
14 | #include <as-layout.h> |
15 | #include <init.h> | |
16 | #include <kern_util.h> | |
17 | #include <mem.h> | |
18 | #include <os.h> | |
19 | #include <proc_mm.h> | |
20 | #include <ptrace_user.h> | |
21 | #include <registers.h> | |
22 | #include <skas.h> | |
23 | #include <skas_ptrace.h> | |
24 | #include <sysdep/stub.h> | |
abaf6977 GS |
25 | |
26 | int is_skas_winch(int pid, int fd, void *data) | |
27 | { | |
17e05209 | 28 | return pid == getpgrp(); |
abaf6977 GS |
29 | } |
30 | ||
f30c2c98 JD |
31 | static int ptrace_dump_regs(int pid) |
32 | { | |
3e6f2ac4 JD |
33 | unsigned long regs[MAX_REG_NR]; |
34 | int i; | |
f30c2c98 | 35 | |
3e6f2ac4 JD |
36 | if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0) |
37 | return -errno; | |
ba180fd4 JD |
38 | |
39 | printk(UM_KERN_ERR "Stub registers -\n"); | |
40 | for (i = 0; i < ARRAY_SIZE(regs); i++) | |
41 | printk(UM_KERN_ERR "\t%d - %lx\n", i, regs[i]); | |
f30c2c98 | 42 | |
3e6f2ac4 | 43 | return 0; |
f30c2c98 JD |
44 | } |
45 | ||
16dd07bc JD |
46 | /* |
47 | * Signals that are OK to receive in the stub - we'll just continue it. | |
48 | * SIGWINCH will happen when UML is inside a detached screen. | |
49 | */ | |
3d5ede6f | 50 | #define STUB_SIG_MASK ((1 << SIGVTALRM) | (1 << SIGWINCH)) |
16dd07bc JD |
51 | |
52 | /* Signals that the stub will finish with - anything else is an error */ | |
ee3d9bd4 | 53 | #define STUB_DONE_MASK (1 << SIGTRAP) |
16dd07bc JD |
54 | |
55 | void wait_stub_done(int pid) | |
abaf6977 | 56 | { |
0974a9ca | 57 | int n, status, err, bad_stop = 0; |
abaf6977 | 58 | |
ba180fd4 | 59 | while (1) { |
4dbed85a | 60 | CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL)); |
ba180fd4 | 61 | if ((n < 0) || !WIFSTOPPED(status)) |
16dd07bc JD |
62 | goto bad_wait; |
63 | ||
ba180fd4 | 64 | if (((1 << WSTOPSIG(status)) & STUB_SIG_MASK) == 0) |
16dd07bc JD |
65 | break; |
66 | ||
67 | err = ptrace(PTRACE_CONT, pid, 0, 0); | |
3e6f2ac4 JD |
68 | if (err) { |
69 | printk(UM_KERN_ERR "wait_stub_done : continue failed, " | |
70 | "errno = %d\n", errno); | |
71 | fatal_sigsegv(); | |
72 | } | |
abaf6977 | 73 | } |
16dd07bc | 74 | |
ba180fd4 | 75 | if (((1 << WSTOPSIG(status)) & STUB_DONE_MASK) != 0) |
16dd07bc | 76 | return; |
0974a9ca RW |
77 | else |
78 | bad_stop = 1; | |
16dd07bc JD |
79 | |
80 | bad_wait: | |
81 | err = ptrace_dump_regs(pid); | |
ba180fd4 JD |
82 | if (err) |
83 | printk(UM_KERN_ERR "Failed to get registers from stub, " | |
84 | "errno = %d\n", -err); | |
3e6f2ac4 JD |
85 | printk(UM_KERN_ERR "wait_stub_done : failed to wait for SIGTRAP, " |
86 | "pid = %d, n = %d, errno = %d, status = 0x%x\n", pid, n, errno, | |
87 | status); | |
0974a9ca RW |
88 | if (bad_stop) |
89 | kill(pid, SIGKILL); | |
90 | else | |
91 | fatal_sigsegv(); | |
abaf6977 GS |
92 | } |
93 | ||
94 | extern unsigned long current_stub_stack(void); | |
95 | ||
99764fa4 | 96 | static void get_skas_faultinfo(int pid, struct faultinfo *fi) |
abaf6977 GS |
97 | { |
98 | int err; | |
99 | ||
ba180fd4 | 100 | if (ptrace_faultinfo) { |
abaf6977 | 101 | err = ptrace(PTRACE_FAULTINFO, pid, 0, fi); |
3e6f2ac4 JD |
102 | if (err) { |
103 | printk(UM_KERN_ERR "get_skas_faultinfo - " | |
104 | "PTRACE_FAULTINFO failed, errno = %d\n", errno); | |
105 | fatal_sigsegv(); | |
106 | } | |
abaf6977 GS |
107 | |
108 | /* Special handling for i386, which has different structs */ | |
109 | if (sizeof(struct ptrace_faultinfo) < sizeof(struct faultinfo)) | |
110 | memset((char *)fi + sizeof(struct ptrace_faultinfo), 0, | |
111 | sizeof(struct faultinfo) - | |
112 | sizeof(struct ptrace_faultinfo)); | |
113 | } | |
114 | else { | |
2f56debd JD |
115 | unsigned long fpregs[FP_SIZE]; |
116 | ||
117 | err = get_fp_registers(pid, fpregs); | |
118 | if (err < 0) { | |
119 | printk(UM_KERN_ERR "save_fp_registers returned %d\n", | |
120 | err); | |
121 | fatal_sigsegv(); | |
122 | } | |
16dd07bc | 123 | err = ptrace(PTRACE_CONT, pid, 0, SIGSEGV); |
3e6f2ac4 JD |
124 | if (err) { |
125 | printk(UM_KERN_ERR "Failed to continue stub, pid = %d, " | |
126 | "errno = %d\n", pid, errno); | |
127 | fatal_sigsegv(); | |
128 | } | |
16dd07bc | 129 | wait_stub_done(pid); |
abaf6977 | 130 | |
ba180fd4 JD |
131 | /* |
132 | * faultinfo is prepared by the stub-segv-handler at start of | |
abaf6977 GS |
133 | * the stub stack page. We just have to copy it. |
134 | */ | |
135 | memcpy(fi, (void *)current_stub_stack(), sizeof(*fi)); | |
2f56debd JD |
136 | |
137 | err = put_fp_registers(pid, fpregs); | |
138 | if (err < 0) { | |
139 | printk(UM_KERN_ERR "put_fp_registers returned %d\n", | |
140 | err); | |
141 | fatal_sigsegv(); | |
142 | } | |
abaf6977 GS |
143 | } |
144 | } | |
145 | ||
77bf4400 | 146 | static void handle_segv(int pid, struct uml_pt_regs * regs) |
abaf6977 | 147 | { |
77bf4400 JD |
148 | get_skas_faultinfo(pid, ®s->faultinfo); |
149 | segv(regs->faultinfo, 0, 1, NULL); | |
abaf6977 GS |
150 | } |
151 | ||
ba180fd4 JD |
152 | /* |
153 | * To use the same value of using_sysemu as the caller, ask it that value | |
154 | * (in local_using_sysemu | |
155 | */ | |
156 | static void handle_trap(int pid, struct uml_pt_regs *regs, | |
157 | int local_using_sysemu) | |
abaf6977 GS |
158 | { |
159 | int err, status; | |
160 | ||
e06173bd JD |
161 | if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END)) |
162 | fatal_sigsegv(); | |
163 | ||
abaf6977 | 164 | /* Mark this as a syscall */ |
18baddda | 165 | UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->gp); |
abaf6977 GS |
166 | |
167 | if (!local_using_sysemu) | |
168 | { | |
966e803a | 169 | err = ptrace(PTRACE_POKEUSER, pid, PT_SYSCALL_NR_OFFSET, |
abaf6977 | 170 | __NR_getpid); |
3e6f2ac4 JD |
171 | if (err < 0) { |
172 | printk(UM_KERN_ERR "handle_trap - nullifying syscall " | |
173 | "failed, errno = %d\n", errno); | |
174 | fatal_sigsegv(); | |
175 | } | |
abaf6977 GS |
176 | |
177 | err = ptrace(PTRACE_SYSCALL, pid, 0, 0); | |
3e6f2ac4 JD |
178 | if (err < 0) { |
179 | printk(UM_KERN_ERR "handle_trap - continuing to end of " | |
180 | "syscall failed, errno = %d\n", errno); | |
181 | fatal_sigsegv(); | |
182 | } | |
abaf6977 | 183 | |
4dbed85a | 184 | CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL)); |
ba180fd4 | 185 | if ((err < 0) || !WIFSTOPPED(status) || |
3e6f2ac4 JD |
186 | (WSTOPSIG(status) != SIGTRAP + 0x80)) { |
187 | err = ptrace_dump_regs(pid); | |
188 | if (err) | |
189 | printk(UM_KERN_ERR "Failed to get registers " | |
ba180fd4 | 190 | "from process, errno = %d\n", -err); |
3e6f2ac4 JD |
191 | printk(UM_KERN_ERR "handle_trap - failed to wait at " |
192 | "end of syscall, errno = %d, status = %d\n", | |
193 | errno, status); | |
194 | fatal_sigsegv(); | |
195 | } | |
abaf6977 GS |
196 | } |
197 | ||
198 | handle_syscall(regs); | |
199 | } | |
200 | ||
201 | extern int __syscall_stub_start; | |
abaf6977 GS |
202 | |
203 | static int userspace_tramp(void *stack) | |
204 | { | |
205 | void *addr; | |
537ae946 | 206 | int err; |
abaf6977 GS |
207 | |
208 | ptrace(PTRACE_TRACEME, 0, 0, 0); | |
209 | ||
a24864a1 | 210 | signal(SIGTERM, SIG_DFL); |
ee3d9bd4 | 211 | signal(SIGWINCH, SIG_IGN); |
a2f018bf | 212 | err = set_interval(); |
3e6f2ac4 JD |
213 | if (err) { |
214 | printk(UM_KERN_ERR "userspace_tramp - setting timer failed, " | |
215 | "errno = %d\n", err); | |
216 | exit(1); | |
217 | } | |
abaf6977 | 218 | |
ba180fd4 JD |
219 | if (!proc_mm) { |
220 | /* | |
221 | * This has a pte, but it can't be mapped in with the usual | |
abaf6977 GS |
222 | * tlb_flush mechanism because this is part of that mechanism |
223 | */ | |
09ee011e | 224 | int fd; |
ba180fd4 | 225 | unsigned long long offset; |
09ee011e | 226 | fd = phys_mapping(to_phys(&__syscall_stub_start), &offset); |
54ae36f2 | 227 | addr = mmap64((void *) STUB_CODE, UM_KERN_PAGE_SIZE, |
09ee011e | 228 | PROT_EXEC, MAP_FIXED | MAP_PRIVATE, fd, offset); |
ba180fd4 | 229 | if (addr == MAP_FAILED) { |
54ae36f2 JD |
230 | printk(UM_KERN_ERR "mapping mmap stub at 0x%lx failed, " |
231 | "errno = %d\n", STUB_CODE, errno); | |
abaf6977 GS |
232 | exit(1); |
233 | } | |
234 | ||
ba180fd4 | 235 | if (stack != NULL) { |
abaf6977 | 236 | fd = phys_mapping(to_phys(stack), &offset); |
54ae36f2 | 237 | addr = mmap((void *) STUB_DATA, |
1ffb9164 | 238 | UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE, |
abaf6977 | 239 | MAP_FIXED | MAP_SHARED, fd, offset); |
ba180fd4 JD |
240 | if (addr == MAP_FAILED) { |
241 | printk(UM_KERN_ERR "mapping segfault stack " | |
54ae36f2 JD |
242 | "at 0x%lx failed, errno = %d\n", |
243 | STUB_DATA, errno); | |
abaf6977 GS |
244 | exit(1); |
245 | } | |
246 | } | |
247 | } | |
ba180fd4 | 248 | if (!ptrace_faultinfo && (stack != NULL)) { |
4b84c69b JD |
249 | struct sigaction sa; |
250 | ||
54ae36f2 | 251 | unsigned long v = STUB_CODE + |
abaf6977 GS |
252 | (unsigned long) stub_segv_handler - |
253 | (unsigned long) &__syscall_stub_start; | |
254 | ||
54ae36f2 | 255 | set_sigstack((void *) STUB_DATA, UM_KERN_PAGE_SIZE); |
4b84c69b | 256 | sigemptyset(&sa.sa_mask); |
9b25fcbd AV |
257 | sa.sa_flags = SA_ONSTACK | SA_NODEFER | SA_SIGINFO; |
258 | sa.sa_sigaction = (void *) v; | |
4b84c69b | 259 | sa.sa_restorer = NULL; |
3e6f2ac4 JD |
260 | if (sigaction(SIGSEGV, &sa, NULL) < 0) { |
261 | printk(UM_KERN_ERR "userspace_tramp - setting SIGSEGV " | |
262 | "handler failed - errno = %d\n", errno); | |
263 | exit(1); | |
264 | } | |
abaf6977 GS |
265 | } |
266 | ||
512b6fb1 | 267 | kill(os_getpid(), SIGSTOP); |
ba180fd4 | 268 | return 0; |
abaf6977 GS |
269 | } |
270 | ||
271 | /* Each element set once, and only accessed by a single processor anyway */ | |
272 | #undef NR_CPUS | |
273 | #define NR_CPUS 1 | |
274 | int userspace_pid[NR_CPUS]; | |
275 | ||
276 | int start_userspace(unsigned long stub_stack) | |
277 | { | |
278 | void *stack; | |
279 | unsigned long sp; | |
3e6f2ac4 | 280 | int pid, status, n, flags, err; |
abaf6977 | 281 | |
c539ab73 JD |
282 | stack = mmap(NULL, UM_KERN_PAGE_SIZE, |
283 | PROT_READ | PROT_WRITE | PROT_EXEC, | |
abaf6977 | 284 | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
3e6f2ac4 JD |
285 | if (stack == MAP_FAILED) { |
286 | err = -errno; | |
287 | printk(UM_KERN_ERR "start_userspace : mmap failed, " | |
b5498832 | 288 | "errno = %d\n", errno); |
3e6f2ac4 JD |
289 | return err; |
290 | } | |
291 | ||
c539ab73 | 292 | sp = (unsigned long) stack + UM_KERN_PAGE_SIZE - sizeof(void *); |
abaf6977 | 293 | |
4dbed85a | 294 | flags = CLONE_FILES; |
ba180fd4 JD |
295 | if (proc_mm) |
296 | flags |= CLONE_VM; | |
4dbed85a SG |
297 | else |
298 | flags |= SIGCHLD; | |
ba180fd4 | 299 | |
abaf6977 | 300 | pid = clone(userspace_tramp, (void *) sp, flags, (void *) stub_stack); |
3e6f2ac4 JD |
301 | if (pid < 0) { |
302 | err = -errno; | |
303 | printk(UM_KERN_ERR "start_userspace : clone failed, " | |
b5498832 | 304 | "errno = %d\n", errno); |
3e6f2ac4 JD |
305 | return err; |
306 | } | |
abaf6977 GS |
307 | |
308 | do { | |
4dbed85a | 309 | CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL)); |
3e6f2ac4 JD |
310 | if (n < 0) { |
311 | err = -errno; | |
312 | printk(UM_KERN_ERR "start_userspace : wait failed, " | |
b5498832 | 313 | "errno = %d\n", errno); |
3e6f2ac4 JD |
314 | goto out_kill; |
315 | } | |
ba180fd4 | 316 | } while (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGVTALRM)); |
abaf6977 | 317 | |
3e6f2ac4 JD |
318 | if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP)) { |
319 | err = -EINVAL; | |
320 | printk(UM_KERN_ERR "start_userspace : expected SIGSTOP, got " | |
b5498832 | 321 | "status = %d\n", status); |
3e6f2ac4 JD |
322 | goto out_kill; |
323 | } | |
abaf6977 | 324 | |
ba180fd4 | 325 | if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL, |
3e6f2ac4 JD |
326 | (void *) PTRACE_O_TRACESYSGOOD) < 0) { |
327 | err = -errno; | |
328 | printk(UM_KERN_ERR "start_userspace : PTRACE_OLDSETOPTIONS " | |
329 | "failed, errno = %d\n", errno); | |
330 | goto out_kill; | |
331 | } | |
abaf6977 | 332 | |
3e6f2ac4 JD |
333 | if (munmap(stack, UM_KERN_PAGE_SIZE) < 0) { |
334 | err = -errno; | |
335 | printk(UM_KERN_ERR "start_userspace : munmap failed, " | |
336 | "errno = %d\n", errno); | |
337 | goto out_kill; | |
338 | } | |
abaf6977 | 339 | |
ba180fd4 | 340 | return pid; |
3e6f2ac4 JD |
341 | |
342 | out_kill: | |
343 | os_kill_ptraced_process(pid, 1); | |
344 | return err; | |
abaf6977 GS |
345 | } |
346 | ||
77bf4400 | 347 | void userspace(struct uml_pt_regs *regs) |
abaf6977 | 348 | { |
d2753a6d JD |
349 | struct itimerval timer; |
350 | unsigned long long nsecs, now; | |
abaf6977 | 351 | int err, status, op, pid = userspace_pid[0]; |
2ea5bc5e JD |
352 | /* To prevent races if using_sysemu changes under us.*/ |
353 | int local_using_sysemu; | |
d3c1cfcd | 354 | siginfo_t si; |
abaf6977 | 355 | |
b8a42095 AV |
356 | /* Handle any immediate reschedules or signals */ |
357 | interrupt_end(); | |
358 | ||
d2753a6d | 359 | if (getitimer(ITIMER_VIRTUAL, &timer)) |
5134d8fe | 360 | printk(UM_KERN_ERR "Failed to get itimer, errno = %d\n", errno); |
1a805219 JD |
361 | nsecs = timer.it_value.tv_sec * UM_NSEC_PER_SEC + |
362 | timer.it_value.tv_usec * UM_NSEC_PER_USEC; | |
d2753a6d JD |
363 | nsecs += os_nsecs(); |
364 | ||
ba180fd4 | 365 | while (1) { |
3e6f2ac4 JD |
366 | /* |
367 | * This can legitimately fail if the process loads a | |
368 | * bogus value into a segment register. It will | |
369 | * segfault and PTRACE_GETREGS will read that value | |
370 | * out of the process. However, PTRACE_SETREGS will | |
371 | * fail. In this case, there is nothing to do but | |
372 | * just kill the process. | |
373 | */ | |
d25f2e12 | 374 | if (ptrace(PTRACE_SETREGS, pid, 0, regs->gp)) |
3e6f2ac4 | 375 | fatal_sigsegv(); |
abaf6977 | 376 | |
fbfe9c84 IL |
377 | if (put_fp_registers(pid, regs->fp)) |
378 | fatal_sigsegv(); | |
379 | ||
abaf6977 GS |
380 | /* Now we set local_using_sysemu to be used for one loop */ |
381 | local_using_sysemu = get_using_sysemu(); | |
382 | ||
2ea5bc5e JD |
383 | op = SELECT_PTRACE_OPERATION(local_using_sysemu, |
384 | singlestepping(NULL)); | |
abaf6977 | 385 | |
3e6f2ac4 JD |
386 | if (ptrace(op, pid, 0, 0)) { |
387 | printk(UM_KERN_ERR "userspace - ptrace continue " | |
388 | "failed, op = %d, errno = %d\n", op, errno); | |
389 | fatal_sigsegv(); | |
390 | } | |
abaf6977 | 391 | |
4dbed85a | 392 | CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL)); |
3e6f2ac4 JD |
393 | if (err < 0) { |
394 | printk(UM_KERN_ERR "userspace - wait failed, " | |
395 | "errno = %d\n", errno); | |
396 | fatal_sigsegv(); | |
397 | } | |
abaf6977 | 398 | |
77bf4400 | 399 | regs->is_user = 1; |
3e6f2ac4 JD |
400 | if (ptrace(PTRACE_GETREGS, pid, 0, regs->gp)) { |
401 | printk(UM_KERN_ERR "userspace - PTRACE_GETREGS failed, " | |
402 | "errno = %d\n", errno); | |
403 | fatal_sigsegv(); | |
404 | } | |
d25f2e12 | 405 | |
fbfe9c84 IL |
406 | if (get_fp_registers(pid, regs->fp)) { |
407 | printk(UM_KERN_ERR "userspace - get_fp_registers failed, " | |
408 | "errno = %d\n", errno); | |
409 | fatal_sigsegv(); | |
410 | } | |
411 | ||
abaf6977 GS |
412 | UPT_SYSCALL_NR(regs) = -1; /* Assume: It's not a syscall */ |
413 | ||
ba180fd4 | 414 | if (WIFSTOPPED(status)) { |
16dd07bc | 415 | int sig = WSTOPSIG(status); |
d3c1cfcd | 416 | |
9a8c1359 | 417 | ptrace(PTRACE_GETSIGINFO, pid, 0, (struct siginfo *)&si); |
d3c1cfcd | 418 | |
5134d8fe | 419 | switch (sig) { |
abaf6977 | 420 | case SIGSEGV: |
ba180fd4 JD |
421 | if (PTRACE_FULL_FAULTINFO || |
422 | !ptrace_faultinfo) { | |
423 | get_skas_faultinfo(pid, | |
424 | ®s->faultinfo); | |
9a8c1359 | 425 | (*sig_info[SIGSEGV])(SIGSEGV, (struct siginfo *)&si, |
d3c1cfcd | 426 | regs); |
16dd07bc | 427 | } |
abaf6977 GS |
428 | else handle_segv(pid, regs); |
429 | break; | |
430 | case SIGTRAP + 0x80: | |
431 | handle_trap(pid, regs, local_using_sysemu); | |
432 | break; | |
433 | case SIGTRAP: | |
9a8c1359 | 434 | relay_signal(SIGTRAP, (struct siginfo *)&si, regs); |
abaf6977 | 435 | break; |
abaf6977 | 436 | case SIGVTALRM: |
d2753a6d | 437 | now = os_nsecs(); |
d25f2e12 | 438 | if (now < nsecs) |
d2753a6d JD |
439 | break; |
440 | block_signals(); | |
9a8c1359 | 441 | (*sig_info[sig])(sig, (struct siginfo *)&si, regs); |
d2753a6d | 442 | unblock_signals(); |
1a805219 JD |
443 | nsecs = timer.it_value.tv_sec * |
444 | UM_NSEC_PER_SEC + | |
445 | timer.it_value.tv_usec * | |
446 | UM_NSEC_PER_USEC; | |
d2753a6d JD |
447 | nsecs += os_nsecs(); |
448 | break; | |
449 | case SIGIO: | |
abaf6977 GS |
450 | case SIGILL: |
451 | case SIGBUS: | |
452 | case SIGFPE: | |
453 | case SIGWINCH: | |
16dd07bc | 454 | block_signals(); |
9a8c1359 | 455 | (*sig_info[sig])(sig, (struct siginfo *)&si, regs); |
16dd07bc | 456 | unblock_signals(); |
abaf6977 GS |
457 | break; |
458 | default: | |
96cee304 | 459 | printk(UM_KERN_ERR "userspace - child stopped " |
ba180fd4 | 460 | "with signal %d\n", sig); |
3e6f2ac4 | 461 | fatal_sigsegv(); |
abaf6977 | 462 | } |
abaf6977 GS |
463 | pid = userspace_pid[0]; |
464 | interrupt_end(); | |
465 | ||
466 | /* Avoid -ERESTARTSYS handling in host */ | |
ba180fd4 | 467 | if (PT_SYSCALL_NR_OFFSET != PT_SYSCALL_RET_OFFSET) |
18baddda | 468 | PT_SYSCALL_NR(regs->gp) = -1; |
abaf6977 GS |
469 | } |
470 | } | |
471 | } | |
abaf6977 | 472 | |
16dd07bc | 473 | static unsigned long thread_regs[MAX_REG_NR]; |
fbfe9c84 | 474 | static unsigned long thread_fp_regs[FP_SIZE]; |
16dd07bc JD |
475 | |
476 | static int __init init_thread_regs(void) | |
477 | { | |
fbfe9c84 | 478 | get_safe_registers(thread_regs, thread_fp_regs); |
16dd07bc | 479 | /* Set parent's instruction pointer to start of clone-stub */ |
54ae36f2 | 480 | thread_regs[REGS_IP_INDEX] = STUB_CODE + |
16dd07bc JD |
481 | (unsigned long) stub_clone_handler - |
482 | (unsigned long) &__syscall_stub_start; | |
54ae36f2 | 483 | thread_regs[REGS_SP_INDEX] = STUB_DATA + UM_KERN_PAGE_SIZE - |
16dd07bc JD |
484 | sizeof(void *); |
485 | #ifdef __SIGNAL_FRAMESIZE | |
486 | thread_regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE; | |
487 | #endif | |
488 | return 0; | |
489 | } | |
490 | ||
491 | __initcall(init_thread_regs); | |
492 | ||
abaf6977 GS |
493 | int copy_context_skas0(unsigned long new_stack, int pid) |
494 | { | |
1a805219 | 495 | struct timeval tv = { .tv_sec = 0, .tv_usec = UM_USEC_PER_SEC / UM_HZ }; |
abaf6977 | 496 | int err; |
abaf6977 GS |
497 | unsigned long current_stack = current_stub_stack(); |
498 | struct stub_data *data = (struct stub_data *) current_stack; | |
499 | struct stub_data *child_data = (struct stub_data *) new_stack; | |
0a7675aa | 500 | unsigned long long new_offset; |
abaf6977 GS |
501 | int new_fd = phys_mapping(to_phys((void *)new_stack), &new_offset); |
502 | ||
ba180fd4 JD |
503 | /* |
504 | * prepare offset and fd of child's stack as argument for parent's | |
abaf6977 GS |
505 | * and child's mmap2 calls |
506 | */ | |
507 | *data = ((struct stub_data) { .offset = MMAP_OFFSET(new_offset), | |
508 | .fd = new_fd, | |
509 | .timer = ((struct itimerval) | |
d2753a6d JD |
510 | { .it_value = tv, |
511 | .it_interval = tv }) }); | |
512 | ||
16dd07bc | 513 | err = ptrace_setregs(pid, thread_regs); |
3e6f2ac4 JD |
514 | if (err < 0) { |
515 | err = -errno; | |
516 | printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_SETREGS " | |
517 | "failed, pid = %d, errno = %d\n", pid, -err); | |
518 | return err; | |
519 | } | |
abaf6977 | 520 | |
fbfe9c84 IL |
521 | err = put_fp_registers(pid, thread_fp_regs); |
522 | if (err < 0) { | |
523 | printk(UM_KERN_ERR "copy_context_skas0 : put_fp_registers " | |
524 | "failed, pid = %d, err = %d\n", pid, err); | |
525 | return err; | |
526 | } | |
527 | ||
abaf6977 GS |
528 | /* set a well known return code for detection of child write failure */ |
529 | child_data->err = 12345678; | |
530 | ||
ba180fd4 JD |
531 | /* |
532 | * Wait, until parent has finished its work: read child's pid from | |
abaf6977 GS |
533 | * parent's stack, and check, if bad result. |
534 | */ | |
16dd07bc | 535 | err = ptrace(PTRACE_CONT, pid, 0, 0); |
3e6f2ac4 JD |
536 | if (err) { |
537 | err = -errno; | |
538 | printk(UM_KERN_ERR "Failed to continue new process, pid = %d, " | |
539 | "errno = %d\n", pid, errno); | |
540 | return err; | |
541 | } | |
542 | ||
16dd07bc | 543 | wait_stub_done(pid); |
abaf6977 GS |
544 | |
545 | pid = data->err; | |
3e6f2ac4 JD |
546 | if (pid < 0) { |
547 | printk(UM_KERN_ERR "copy_context_skas0 - stub-parent reports " | |
548 | "error %d\n", -pid); | |
549 | return pid; | |
550 | } | |
abaf6977 | 551 | |
ba180fd4 JD |
552 | /* |
553 | * Wait, until child has finished too: read child's result from | |
abaf6977 GS |
554 | * child's stack and check it. |
555 | */ | |
16dd07bc | 556 | wait_stub_done(pid); |
3e6f2ac4 JD |
557 | if (child_data->err != STUB_DATA) { |
558 | printk(UM_KERN_ERR "copy_context_skas0 - stub-child reports " | |
559 | "error %ld\n", child_data->err); | |
560 | err = child_data->err; | |
561 | goto out_kill; | |
562 | } | |
abaf6977 GS |
563 | |
564 | if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL, | |
3e6f2ac4 JD |
565 | (void *)PTRACE_O_TRACESYSGOOD) < 0) { |
566 | err = -errno; | |
567 | printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_OLDSETOPTIONS " | |
568 | "failed, errno = %d\n", errno); | |
569 | goto out_kill; | |
570 | } | |
abaf6977 GS |
571 | |
572 | return pid; | |
3e6f2ac4 JD |
573 | |
574 | out_kill: | |
575 | os_kill_ptraced_process(pid, 1); | |
576 | return err; | |
abaf6977 GS |
577 | } |
578 | ||
579 | /* | |
580 | * This is used only, if stub pages are needed, while proc_mm is | |
ef0470c0 | 581 | * available. Opening /proc/mm creates a new mm_context, which lacks |
abaf6977 GS |
582 | * the stub-pages. Thus, we map them using /proc/mm-fd |
583 | */ | |
3e6f2ac4 JD |
584 | int map_stub_pages(int fd, unsigned long code, unsigned long data, |
585 | unsigned long stack) | |
abaf6977 GS |
586 | { |
587 | struct proc_mm_op mmop; | |
588 | int n; | |
0a7675aa | 589 | unsigned long long code_offset; |
09ee011e JD |
590 | int code_fd = phys_mapping(to_phys((void *) &__syscall_stub_start), |
591 | &code_offset); | |
abaf6977 GS |
592 | |
593 | mmop = ((struct proc_mm_op) { .op = MM_MMAP, | |
594 | .u = | |
595 | { .mmap = | |
596 | { .addr = code, | |
c539ab73 | 597 | .len = UM_KERN_PAGE_SIZE, |
abaf6977 GS |
598 | .prot = PROT_EXEC, |
599 | .flags = MAP_FIXED | MAP_PRIVATE, | |
09ee011e JD |
600 | .fd = code_fd, |
601 | .offset = code_offset | |
abaf6977 | 602 | } } }); |
a61f334f | 603 | CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop))); |
ba180fd4 | 604 | if (n != sizeof(mmop)) { |
a61f334f | 605 | n = errno; |
ba180fd4 JD |
606 | printk(UM_KERN_ERR "mmap args - addr = 0x%lx, fd = %d, " |
607 | "offset = %llx\n", code, code_fd, | |
608 | (unsigned long long) code_offset); | |
3e6f2ac4 JD |
609 | printk(UM_KERN_ERR "map_stub_pages : /proc/mm map for code " |
610 | "failed, err = %d\n", n); | |
611 | return -n; | |
b4cf95c6 | 612 | } |
abaf6977 | 613 | |
ba180fd4 | 614 | if (stack) { |
0a7675aa | 615 | unsigned long long map_offset; |
abaf6977 GS |
616 | int map_fd = phys_mapping(to_phys((void *)stack), &map_offset); |
617 | mmop = ((struct proc_mm_op) | |
618 | { .op = MM_MMAP, | |
619 | .u = | |
620 | { .mmap = | |
621 | { .addr = data, | |
c539ab73 | 622 | .len = UM_KERN_PAGE_SIZE, |
abaf6977 GS |
623 | .prot = PROT_READ | PROT_WRITE, |
624 | .flags = MAP_FIXED | MAP_SHARED, | |
625 | .fd = map_fd, | |
626 | .offset = map_offset | |
627 | } } }); | |
a61f334f | 628 | CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop))); |
3e6f2ac4 JD |
629 | if (n != sizeof(mmop)) { |
630 | n = errno; | |
631 | printk(UM_KERN_ERR "map_stub_pages : /proc/mm map for " | |
632 | "data failed, err = %d\n", n); | |
633 | return -n; | |
634 | } | |
abaf6977 | 635 | } |
3e6f2ac4 JD |
636 | |
637 | return 0; | |
abaf6977 GS |
638 | } |
639 | ||
3c917350 | 640 | void new_thread(void *stack, jmp_buf *buf, void (*handler)(void)) |
abaf6977 | 641 | { |
3c917350 | 642 | (*buf)[0].JB_IP = (unsigned long) handler; |
e1a79c40 JD |
643 | (*buf)[0].JB_SP = (unsigned long) stack + UM_THREAD_SIZE - |
644 | sizeof(void *); | |
abaf6977 GS |
645 | } |
646 | ||
e2216feb | 647 | #define INIT_JMP_NEW_THREAD 0 |
3c917350 JD |
648 | #define INIT_JMP_CALLBACK 1 |
649 | #define INIT_JMP_HALT 2 | |
650 | #define INIT_JMP_REBOOT 3 | |
abaf6977 | 651 | |
3c917350 | 652 | void switch_threads(jmp_buf *me, jmp_buf *you) |
abaf6977 | 653 | { |
ba180fd4 | 654 | if (UML_SETJMP(me) == 0) |
3c917350 | 655 | UML_LONGJMP(you, 1); |
abaf6977 GS |
656 | } |
657 | ||
ad28e029 | 658 | static jmp_buf initial_jmpbuf; |
abaf6977 GS |
659 | |
660 | /* XXX Make these percpu */ | |
661 | static void (*cb_proc)(void *arg); | |
662 | static void *cb_arg; | |
ad28e029 | 663 | static jmp_buf *cb_back; |
abaf6977 | 664 | |
3c917350 | 665 | int start_idle_thread(void *stack, jmp_buf *switch_buf) |
abaf6977 | 666 | { |
a5df0d1a | 667 | int n; |
abaf6977 | 668 | |
00361683 | 669 | set_handler(SIGWINCH); |
abaf6977 | 670 | |
77f6af77 JD |
671 | /* |
672 | * Can't use UML_SETJMP or UML_LONGJMP here because they save | |
673 | * and restore signals, with the possible side-effect of | |
674 | * trying to handle any signals which came when they were | |
675 | * blocked, which can't be done on this stack. | |
676 | * Signals must be blocked when jumping back here and restored | |
677 | * after returning to the jumper. | |
678 | */ | |
679 | n = setjmp(initial_jmpbuf); | |
5134d8fe | 680 | switch (n) { |
abaf6977 | 681 | case INIT_JMP_NEW_THREAD: |
3c917350 JD |
682 | (*switch_buf)[0].JB_IP = (unsigned long) new_thread_handler; |
683 | (*switch_buf)[0].JB_SP = (unsigned long) stack + | |
e1a79c40 | 684 | UM_THREAD_SIZE - sizeof(void *); |
abaf6977 GS |
685 | break; |
686 | case INIT_JMP_CALLBACK: | |
687 | (*cb_proc)(cb_arg); | |
77f6af77 | 688 | longjmp(*cb_back, 1); |
abaf6977 GS |
689 | break; |
690 | case INIT_JMP_HALT: | |
691 | kmalloc_ok = 0; | |
ba180fd4 | 692 | return 0; |
abaf6977 GS |
693 | case INIT_JMP_REBOOT: |
694 | kmalloc_ok = 0; | |
ba180fd4 | 695 | return 1; |
abaf6977 | 696 | default: |
3e6f2ac4 JD |
697 | printk(UM_KERN_ERR "Bad sigsetjmp return in " |
698 | "start_idle_thread - %d\n", n); | |
699 | fatal_sigsegv(); | |
abaf6977 | 700 | } |
77f6af77 | 701 | longjmp(*switch_buf, 1); |
abaf6977 GS |
702 | } |
703 | ||
704 | void initial_thread_cb_skas(void (*proc)(void *), void *arg) | |
705 | { | |
ad28e029 | 706 | jmp_buf here; |
abaf6977 GS |
707 | |
708 | cb_proc = proc; | |
709 | cb_arg = arg; | |
710 | cb_back = &here; | |
711 | ||
712 | block_signals(); | |
ba180fd4 | 713 | if (UML_SETJMP(&here) == 0) |
ad28e029 | 714 | UML_LONGJMP(&initial_jmpbuf, INIT_JMP_CALLBACK); |
abaf6977 GS |
715 | unblock_signals(); |
716 | ||
717 | cb_proc = NULL; | |
718 | cb_arg = NULL; | |
719 | cb_back = NULL; | |
720 | } | |
721 | ||
722 | void halt_skas(void) | |
723 | { | |
724 | block_signals(); | |
ad28e029 | 725 | UML_LONGJMP(&initial_jmpbuf, INIT_JMP_HALT); |
abaf6977 GS |
726 | } |
727 | ||
728 | void reboot_skas(void) | |
729 | { | |
730 | block_signals(); | |
ad28e029 | 731 | UML_LONGJMP(&initial_jmpbuf, INIT_JMP_REBOOT); |
abaf6977 GS |
732 | } |
733 | ||
77bf4400 | 734 | void __switch_mm(struct mm_id *mm_idp) |
abaf6977 GS |
735 | { |
736 | int err; | |
737 | ||
77bf4400 | 738 | /* FIXME: need cpu pid in __switch_mm */ |
ba180fd4 | 739 | if (proc_mm) { |
abaf6977 GS |
740 | err = ptrace(PTRACE_SWITCH_MM, userspace_pid[0], 0, |
741 | mm_idp->u.mm_fd); | |
3e6f2ac4 JD |
742 | if (err) { |
743 | printk(UM_KERN_ERR "__switch_mm - PTRACE_SWITCH_MM " | |
744 | "failed, errno = %d\n", errno); | |
745 | fatal_sigsegv(); | |
746 | } | |
abaf6977 GS |
747 | } |
748 | else userspace_pid[0] = mm_idp->u.pid; | |
749 | } |