Commit | Line | Data |
---|---|---|
5526b7e4 | 1 | /* linux/arch/sparc/kernel/signal.c |
1da177e4 LT |
2 | * |
3 | * Copyright (C) 1991, 1992 Linus Torvalds | |
4 | * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) | |
5 | * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx) | |
6 | * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be) | |
7 | */ | |
8 | ||
1da177e4 LT |
9 | #include <linux/sched.h> |
10 | #include <linux/kernel.h> | |
11 | #include <linux/signal.h> | |
12 | #include <linux/errno.h> | |
13 | #include <linux/wait.h> | |
14 | #include <linux/ptrace.h> | |
15 | #include <linux/unistd.h> | |
16 | #include <linux/mm.h> | |
17 | #include <linux/tty.h> | |
18 | #include <linux/smp.h> | |
1da177e4 LT |
19 | #include <linux/binfmts.h> /* do_coredum */ |
20 | #include <linux/bitops.h> | |
5a157d5b | 21 | #include <linux/tracehook.h> |
1da177e4 LT |
22 | |
23 | #include <asm/uaccess.h> | |
24 | #include <asm/ptrace.h> | |
1da177e4 LT |
25 | #include <asm/pgalloc.h> |
26 | #include <asm/pgtable.h> | |
27 | #include <asm/cacheflush.h> /* flush_sig_insns */ | |
28 | ||
29 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
30 | ||
31 | extern void fpsave(unsigned long *fpregs, unsigned long *fsr, | |
32 | void *fpqueue, unsigned long *fpqdepth); | |
33 | extern void fpload(unsigned long *fpregs, unsigned long *fsr); | |
34 | ||
5526b7e4 | 35 | struct signal_frame { |
1da177e4 | 36 | struct sparc_stackf ss; |
4d7b92ad | 37 | __siginfo32_t info; |
1da177e4 LT |
38 | __siginfo_fpu_t __user *fpu_save; |
39 | unsigned long insns[2] __attribute__ ((aligned (8))); | |
40 | unsigned int extramask[_NSIG_WORDS - 1]; | |
41 | unsigned int extra_size; /* Should be 0 */ | |
42 | __siginfo_fpu_t fpu_state; | |
43 | }; | |
44 | ||
45 | struct rt_signal_frame { | |
46 | struct sparc_stackf ss; | |
47 | siginfo_t info; | |
48 | struct pt_regs regs; | |
49 | sigset_t mask; | |
50 | __siginfo_fpu_t __user *fpu_save; | |
51 | unsigned int insns[2]; | |
52 | stack_t stack; | |
53 | unsigned int extra_size; /* Should be 0 */ | |
54 | __siginfo_fpu_t fpu_state; | |
55 | }; | |
56 | ||
57 | /* Align macros */ | |
5526b7e4 | 58 | #define SF_ALIGNEDSZ (((sizeof(struct signal_frame) + 7) & (~7))) |
1da177e4 LT |
59 | #define RT_ALIGNEDSZ (((sizeof(struct rt_signal_frame) + 7) & (~7))) |
60 | ||
2d7d5f05 | 61 | static int _sigpause_common(old_sigset_t set) |
1da177e4 | 62 | { |
1da177e4 LT |
63 | set &= _BLOCKABLE; |
64 | spin_lock_irq(¤t->sighand->siglock); | |
2d7d5f05 | 65 | current->saved_sigmask = current->blocked; |
1da177e4 LT |
66 | siginitset(¤t->blocked, set); |
67 | recalc_sigpending(); | |
68 | spin_unlock_irq(¤t->sighand->siglock); | |
69 | ||
2d7d5f05 DM |
70 | current->state = TASK_INTERRUPTIBLE; |
71 | schedule(); | |
72 | set_thread_flag(TIF_RESTORE_SIGMASK); | |
1da177e4 | 73 | |
2d7d5f05 | 74 | return -ERESTARTNOHAND; |
1da177e4 LT |
75 | } |
76 | ||
2d7d5f05 | 77 | asmlinkage int sys_sigsuspend(old_sigset_t set) |
1da177e4 | 78 | { |
2d7d5f05 | 79 | return _sigpause_common(set); |
1da177e4 LT |
80 | } |
81 | ||
82 | static inline int | |
83 | restore_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu) | |
84 | { | |
85 | int err; | |
86 | #ifdef CONFIG_SMP | |
87 | if (test_tsk_thread_flag(current, TIF_USEDFPU)) | |
88 | regs->psr &= ~PSR_EF; | |
89 | #else | |
90 | if (current == last_task_used_math) { | |
91 | last_task_used_math = NULL; | |
92 | regs->psr &= ~PSR_EF; | |
93 | } | |
94 | #endif | |
95 | set_used_math(); | |
96 | clear_tsk_thread_flag(current, TIF_USEDFPU); | |
97 | ||
98 | if (!access_ok(VERIFY_READ, fpu, sizeof(*fpu))) | |
99 | return -EFAULT; | |
100 | ||
101 | err = __copy_from_user(¤t->thread.float_regs[0], &fpu->si_float_regs[0], | |
102 | (sizeof(unsigned long) * 32)); | |
103 | err |= __get_user(current->thread.fsr, &fpu->si_fsr); | |
104 | err |= __get_user(current->thread.fpqdepth, &fpu->si_fpqdepth); | |
105 | if (current->thread.fpqdepth != 0) | |
106 | err |= __copy_from_user(¤t->thread.fpqueue[0], | |
107 | &fpu->si_fpqueue[0], | |
108 | ((sizeof(unsigned long) + | |
109 | (sizeof(unsigned long *)))*16)); | |
110 | return err; | |
111 | } | |
112 | ||
5526b7e4 | 113 | asmlinkage void do_sigreturn(struct pt_regs *regs) |
1da177e4 | 114 | { |
5526b7e4 | 115 | struct signal_frame __user *sf; |
1da177e4 LT |
116 | unsigned long up_psr, pc, npc; |
117 | sigset_t set; | |
118 | __siginfo_fpu_t __user *fpu_save; | |
119 | int err; | |
120 | ||
5526b7e4 DM |
121 | /* Always make any pending restarted system calls return -EINTR */ |
122 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
123 | ||
124 | synchronize_user_stack(); | |
125 | ||
126 | sf = (struct signal_frame __user *) regs->u_regs[UREG_FP]; | |
1da177e4 LT |
127 | |
128 | /* 1. Make sure we are not getting garbage from the user */ | |
129 | if (!access_ok(VERIFY_READ, sf, sizeof(*sf))) | |
130 | goto segv_and_exit; | |
131 | ||
132 | if (((unsigned long) sf) & 3) | |
133 | goto segv_and_exit; | |
134 | ||
135 | err = __get_user(pc, &sf->info.si_regs.pc); | |
136 | err |= __get_user(npc, &sf->info.si_regs.npc); | |
137 | ||
138 | if ((pc | npc) & 3) | |
139 | goto segv_and_exit; | |
140 | ||
141 | /* 2. Restore the state */ | |
142 | up_psr = regs->psr; | |
143 | err |= __copy_from_user(regs, &sf->info.si_regs, sizeof(struct pt_regs)); | |
144 | ||
145 | /* User can only change condition codes and FPU enabling in %psr. */ | |
146 | regs->psr = (up_psr & ~(PSR_ICC | PSR_EF)) | |
147 | | (regs->psr & (PSR_ICC | PSR_EF)); | |
148 | ||
28e61036 DM |
149 | /* Prevent syscall restart. */ |
150 | pt_regs_clear_syscall(regs); | |
151 | ||
1da177e4 LT |
152 | err |= __get_user(fpu_save, &sf->fpu_save); |
153 | ||
154 | if (fpu_save) | |
155 | err |= restore_fpu_state(regs, fpu_save); | |
156 | ||
157 | /* This is pretty much atomic, no amount locking would prevent | |
158 | * the races which exist anyways. | |
159 | */ | |
160 | err |= __get_user(set.sig[0], &sf->info.si_mask); | |
161 | err |= __copy_from_user(&set.sig[1], &sf->extramask, | |
162 | (_NSIG_WORDS-1) * sizeof(unsigned int)); | |
163 | ||
164 | if (err) | |
165 | goto segv_and_exit; | |
166 | ||
167 | sigdelsetmask(&set, ~_BLOCKABLE); | |
168 | spin_lock_irq(¤t->sighand->siglock); | |
169 | current->blocked = set; | |
170 | recalc_sigpending(); | |
171 | spin_unlock_irq(¤t->sighand->siglock); | |
172 | return; | |
173 | ||
174 | segv_and_exit: | |
175 | force_sig(SIGSEGV, current); | |
176 | } | |
177 | ||
1da177e4 LT |
178 | asmlinkage void do_rt_sigreturn(struct pt_regs *regs) |
179 | { | |
180 | struct rt_signal_frame __user *sf; | |
181 | unsigned int psr, pc, npc; | |
182 | __siginfo_fpu_t __user *fpu_save; | |
183 | mm_segment_t old_fs; | |
184 | sigset_t set; | |
185 | stack_t st; | |
186 | int err; | |
187 | ||
188 | synchronize_user_stack(); | |
189 | sf = (struct rt_signal_frame __user *) regs->u_regs[UREG_FP]; | |
190 | if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) || | |
191 | (((unsigned long) sf) & 0x03)) | |
192 | goto segv; | |
193 | ||
194 | err = __get_user(pc, &sf->regs.pc); | |
195 | err |= __get_user(npc, &sf->regs.npc); | |
196 | err |= ((pc | npc) & 0x03); | |
197 | ||
198 | err |= __get_user(regs->y, &sf->regs.y); | |
199 | err |= __get_user(psr, &sf->regs.psr); | |
200 | ||
201 | err |= __copy_from_user(®s->u_regs[UREG_G1], | |
202 | &sf->regs.u_regs[UREG_G1], 15 * sizeof(u32)); | |
203 | ||
204 | regs->psr = (regs->psr & ~PSR_ICC) | (psr & PSR_ICC); | |
205 | ||
28e61036 DM |
206 | /* Prevent syscall restart. */ |
207 | pt_regs_clear_syscall(regs); | |
208 | ||
1da177e4 LT |
209 | err |= __get_user(fpu_save, &sf->fpu_save); |
210 | ||
211 | if (fpu_save) | |
212 | err |= restore_fpu_state(regs, fpu_save); | |
213 | err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t)); | |
214 | ||
215 | err |= __copy_from_user(&st, &sf->stack, sizeof(stack_t)); | |
216 | ||
217 | if (err) | |
218 | goto segv; | |
219 | ||
220 | regs->pc = pc; | |
221 | regs->npc = npc; | |
222 | ||
223 | /* It is more difficult to avoid calling this function than to | |
224 | * call it and ignore errors. | |
225 | */ | |
226 | old_fs = get_fs(); | |
227 | set_fs(KERNEL_DS); | |
228 | do_sigaltstack((const stack_t __user *) &st, NULL, (unsigned long)sf); | |
229 | set_fs(old_fs); | |
230 | ||
231 | sigdelsetmask(&set, ~_BLOCKABLE); | |
232 | spin_lock_irq(¤t->sighand->siglock); | |
233 | current->blocked = set; | |
234 | recalc_sigpending(); | |
235 | spin_unlock_irq(¤t->sighand->siglock); | |
236 | return; | |
237 | segv: | |
238 | force_sig(SIGSEGV, current); | |
239 | } | |
240 | ||
241 | /* Checks if the fp is valid */ | |
242 | static inline int invalid_frame_pointer(void __user *fp, int fplen) | |
243 | { | |
244 | if ((((unsigned long) fp) & 7) || | |
245 | !__access_ok((unsigned long)fp, fplen) || | |
246 | ((sparc_cpu_model == sun4 || sparc_cpu_model == sun4c) && | |
247 | ((unsigned long) fp < 0xe0000000 && (unsigned long) fp >= 0x20000000))) | |
248 | return 1; | |
249 | ||
250 | return 0; | |
251 | } | |
252 | ||
253 | static inline void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, unsigned long framesize) | |
254 | { | |
dc5dc7e6 | 255 | unsigned long sp = regs->u_regs[UREG_FP]; |
1da177e4 | 256 | |
dc5dc7e6 DM |
257 | /* |
258 | * If we are on the alternate signal stack and would overflow it, don't. | |
259 | * Return an always-bogus address instead so we will die with SIGSEGV. | |
260 | */ | |
261 | if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) | |
262 | return (void __user *) -1L; | |
1da177e4 LT |
263 | |
264 | /* This is the X/Open sanctioned signal stack switching. */ | |
265 | if (sa->sa_flags & SA_ONSTACK) { | |
dc5dc7e6 | 266 | if (sas_ss_flags(sp) == 0) |
1da177e4 LT |
267 | sp = current->sas_ss_sp + current->sas_ss_size; |
268 | } | |
dc5dc7e6 | 269 | |
f036d9f3 DM |
270 | sp -= framesize; |
271 | ||
dc5dc7e6 DM |
272 | /* Always align the stack frame. This handles two cases. First, |
273 | * sigaltstack need not be mindful of platform specific stack | |
274 | * alignment. Second, if we took this signal because the stack | |
275 | * is not aligned properly, we'd like to take the signal cleanly | |
276 | * and report that. | |
277 | */ | |
f036d9f3 | 278 | sp &= ~15UL; |
dc5dc7e6 | 279 | |
f036d9f3 | 280 | return (void __user *) sp; |
1da177e4 LT |
281 | } |
282 | ||
1da177e4 LT |
283 | static inline int |
284 | save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu) | |
285 | { | |
286 | int err = 0; | |
287 | #ifdef CONFIG_SMP | |
288 | if (test_tsk_thread_flag(current, TIF_USEDFPU)) { | |
289 | put_psr(get_psr() | PSR_EF); | |
290 | fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, | |
291 | ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); | |
292 | regs->psr &= ~(PSR_EF); | |
293 | clear_tsk_thread_flag(current, TIF_USEDFPU); | |
294 | } | |
295 | #else | |
296 | if (current == last_task_used_math) { | |
297 | put_psr(get_psr() | PSR_EF); | |
298 | fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, | |
299 | ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); | |
300 | last_task_used_math = NULL; | |
301 | regs->psr &= ~(PSR_EF); | |
302 | } | |
303 | #endif | |
304 | err |= __copy_to_user(&fpu->si_float_regs[0], | |
305 | ¤t->thread.float_regs[0], | |
306 | (sizeof(unsigned long) * 32)); | |
307 | err |= __put_user(current->thread.fsr, &fpu->si_fsr); | |
308 | err |= __put_user(current->thread.fpqdepth, &fpu->si_fpqdepth); | |
309 | if (current->thread.fpqdepth != 0) | |
310 | err |= __copy_to_user(&fpu->si_fpqueue[0], | |
311 | ¤t->thread.fpqueue[0], | |
312 | ((sizeof(unsigned long) + | |
313 | (sizeof(unsigned long *)))*16)); | |
314 | clear_used_math(); | |
315 | return err; | |
316 | } | |
317 | ||
5526b7e4 DM |
318 | static void setup_frame(struct k_sigaction *ka, struct pt_regs *regs, |
319 | int signo, sigset_t *oldset) | |
1da177e4 | 320 | { |
5526b7e4 | 321 | struct signal_frame __user *sf; |
1da177e4 LT |
322 | int sigframe_size, err; |
323 | ||
324 | /* 1. Make sure everything is clean */ | |
325 | synchronize_user_stack(); | |
326 | ||
5526b7e4 | 327 | sigframe_size = SF_ALIGNEDSZ; |
1da177e4 LT |
328 | if (!used_math()) |
329 | sigframe_size -= sizeof(__siginfo_fpu_t); | |
330 | ||
5526b7e4 | 331 | sf = (struct signal_frame __user *) |
1da177e4 LT |
332 | get_sigframe(&ka->sa, regs, sigframe_size); |
333 | ||
334 | if (invalid_frame_pointer(sf, sigframe_size)) | |
335 | goto sigill_and_return; | |
336 | ||
337 | if (current_thread_info()->w_saved != 0) | |
338 | goto sigill_and_return; | |
339 | ||
340 | /* 2. Save the current process state */ | |
341 | err = __copy_to_user(&sf->info.si_regs, regs, sizeof(struct pt_regs)); | |
342 | ||
343 | err |= __put_user(0, &sf->extra_size); | |
344 | ||
345 | if (used_math()) { | |
346 | err |= save_fpu_state(regs, &sf->fpu_state); | |
347 | err |= __put_user(&sf->fpu_state, &sf->fpu_save); | |
348 | } else { | |
349 | err |= __put_user(0, &sf->fpu_save); | |
350 | } | |
351 | ||
352 | err |= __put_user(oldset->sig[0], &sf->info.si_mask); | |
353 | err |= __copy_to_user(sf->extramask, &oldset->sig[1], | |
354 | (_NSIG_WORDS - 1) * sizeof(unsigned int)); | |
355 | err |= __copy_to_user(sf, (char *) regs->u_regs[UREG_FP], | |
4d7b92ad | 356 | sizeof(struct reg_window32)); |
1da177e4 LT |
357 | if (err) |
358 | goto sigsegv; | |
359 | ||
360 | /* 3. signal handler back-trampoline and parameters */ | |
361 | regs->u_regs[UREG_FP] = (unsigned long) sf; | |
362 | regs->u_regs[UREG_I0] = signo; | |
363 | regs->u_regs[UREG_I1] = (unsigned long) &sf->info; | |
364 | regs->u_regs[UREG_I2] = (unsigned long) &sf->info; | |
365 | ||
366 | /* 4. signal handler */ | |
367 | regs->pc = (unsigned long) ka->sa.sa_handler; | |
368 | regs->npc = (regs->pc + 4); | |
369 | ||
370 | /* 5. return to kernel instructions */ | |
371 | if (ka->ka_restorer) | |
372 | regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer; | |
373 | else { | |
374 | regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2); | |
375 | ||
376 | /* mov __NR_sigreturn, %g1 */ | |
377 | err |= __put_user(0x821020d8, &sf->insns[0]); | |
378 | ||
379 | /* t 0x10 */ | |
380 | err |= __put_user(0x91d02010, &sf->insns[1]); | |
381 | if (err) | |
382 | goto sigsegv; | |
383 | ||
384 | /* Flush instruction space. */ | |
385 | flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0])); | |
386 | } | |
387 | return; | |
388 | ||
389 | sigill_and_return: | |
390 | do_exit(SIGILL); | |
391 | sigsegv: | |
392 | force_sigsegv(signo, current); | |
393 | } | |
394 | ||
5526b7e4 DM |
395 | static void setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs, |
396 | int signo, sigset_t *oldset, siginfo_t *info) | |
1da177e4 LT |
397 | { |
398 | struct rt_signal_frame __user *sf; | |
399 | int sigframe_size; | |
400 | unsigned int psr; | |
401 | int err; | |
402 | ||
403 | synchronize_user_stack(); | |
404 | sigframe_size = RT_ALIGNEDSZ; | |
405 | if (!used_math()) | |
406 | sigframe_size -= sizeof(__siginfo_fpu_t); | |
407 | sf = (struct rt_signal_frame __user *) | |
408 | get_sigframe(&ka->sa, regs, sigframe_size); | |
409 | if (invalid_frame_pointer(sf, sigframe_size)) | |
410 | goto sigill; | |
411 | if (current_thread_info()->w_saved != 0) | |
412 | goto sigill; | |
413 | ||
414 | err = __put_user(regs->pc, &sf->regs.pc); | |
415 | err |= __put_user(regs->npc, &sf->regs.npc); | |
416 | err |= __put_user(regs->y, &sf->regs.y); | |
417 | psr = regs->psr; | |
418 | if (used_math()) | |
419 | psr |= PSR_EF; | |
420 | err |= __put_user(psr, &sf->regs.psr); | |
421 | err |= __copy_to_user(&sf->regs.u_regs, regs->u_regs, sizeof(regs->u_regs)); | |
422 | err |= __put_user(0, &sf->extra_size); | |
423 | ||
424 | if (psr & PSR_EF) { | |
425 | err |= save_fpu_state(regs, &sf->fpu_state); | |
426 | err |= __put_user(&sf->fpu_state, &sf->fpu_save); | |
427 | } else { | |
428 | err |= __put_user(0, &sf->fpu_save); | |
429 | } | |
430 | err |= __copy_to_user(&sf->mask, &oldset->sig[0], sizeof(sigset_t)); | |
431 | ||
432 | /* Setup sigaltstack */ | |
433 | err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp); | |
434 | err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags); | |
435 | err |= __put_user(current->sas_ss_size, &sf->stack.ss_size); | |
436 | ||
437 | err |= __copy_to_user(sf, (char *) regs->u_regs[UREG_FP], | |
4d7b92ad | 438 | sizeof(struct reg_window32)); |
1da177e4 LT |
439 | |
440 | err |= copy_siginfo_to_user(&sf->info, info); | |
441 | ||
442 | if (err) | |
443 | goto sigsegv; | |
444 | ||
445 | regs->u_regs[UREG_FP] = (unsigned long) sf; | |
446 | regs->u_regs[UREG_I0] = signo; | |
447 | regs->u_regs[UREG_I1] = (unsigned long) &sf->info; | |
448 | regs->u_regs[UREG_I2] = (unsigned long) &sf->regs; | |
449 | ||
450 | regs->pc = (unsigned long) ka->sa.sa_handler; | |
451 | regs->npc = (regs->pc + 4); | |
452 | ||
453 | if (ka->ka_restorer) | |
454 | regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer; | |
455 | else { | |
456 | regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2); | |
457 | ||
458 | /* mov __NR_sigreturn, %g1 */ | |
459 | err |= __put_user(0x821020d8, &sf->insns[0]); | |
460 | ||
461 | /* t 0x10 */ | |
462 | err |= __put_user(0x91d02010, &sf->insns[1]); | |
463 | if (err) | |
464 | goto sigsegv; | |
465 | ||
466 | /* Flush instruction space. */ | |
467 | flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0])); | |
468 | } | |
469 | return; | |
470 | ||
471 | sigill: | |
472 | do_exit(SIGILL); | |
473 | sigsegv: | |
474 | force_sigsegv(signo, current); | |
475 | } | |
476 | ||
1da177e4 LT |
477 | static inline void |
478 | handle_signal(unsigned long signr, struct k_sigaction *ka, | |
ec98c6b9 | 479 | siginfo_t *info, sigset_t *oldset, struct pt_regs *regs) |
1da177e4 | 480 | { |
ec98c6b9 | 481 | if (ka->sa.sa_flags & SA_SIGINFO) |
5526b7e4 | 482 | setup_rt_frame(ka, regs, signr, oldset, info); |
ec98c6b9 | 483 | else |
5526b7e4 | 484 | setup_frame(ka, regs, signr, oldset); |
ec98c6b9 | 485 | |
69be8f18 SR |
486 | spin_lock_irq(¤t->sighand->siglock); |
487 | sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); | |
488 | if (!(ka->sa.sa_flags & SA_NOMASK)) | |
1da177e4 | 489 | sigaddset(¤t->blocked, signr); |
69be8f18 SR |
490 | recalc_sigpending(); |
491 | spin_unlock_irq(¤t->sighand->siglock); | |
1da177e4 LT |
492 | } |
493 | ||
494 | static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs, | |
495 | struct sigaction *sa) | |
496 | { | |
497 | switch(regs->u_regs[UREG_I0]) { | |
498 | case ERESTART_RESTARTBLOCK: | |
499 | case ERESTARTNOHAND: | |
500 | no_system_call_restart: | |
501 | regs->u_regs[UREG_I0] = EINTR; | |
502 | regs->psr |= PSR_C; | |
503 | break; | |
504 | case ERESTARTSYS: | |
505 | if (!(sa->sa_flags & SA_RESTART)) | |
506 | goto no_system_call_restart; | |
507 | /* fallthrough */ | |
508 | case ERESTARTNOINTR: | |
509 | regs->u_regs[UREG_I0] = orig_i0; | |
510 | regs->pc -= 4; | |
511 | regs->npc -= 4; | |
512 | } | |
513 | } | |
514 | ||
515 | /* Note that 'init' is a special process: it doesn't get signals it doesn't | |
516 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
517 | * mistake. | |
518 | */ | |
5a157d5b | 519 | static void do_signal(struct pt_regs *regs, unsigned long orig_i0) |
1da177e4 | 520 | { |
1da177e4 | 521 | struct k_sigaction ka; |
28e61036 | 522 | int restart_syscall; |
2d7d5f05 | 523 | sigset_t *oldset; |
28e61036 DM |
524 | siginfo_t info; |
525 | int signr; | |
1da177e4 | 526 | |
28e61036 DM |
527 | if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C)) |
528 | restart_syscall = 1; | |
529 | else | |
530 | restart_syscall = 0; | |
1da177e4 | 531 | |
2d7d5f05 DM |
532 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) |
533 | oldset = ¤t->saved_sigmask; | |
534 | else | |
1da177e4 LT |
535 | oldset = ¤t->blocked; |
536 | ||
28e61036 DM |
537 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); |
538 | ||
539 | /* If the debugger messes with the program counter, it clears | |
540 | * the software "in syscall" bit, directing us to not perform | |
541 | * a syscall restart. | |
542 | */ | |
543 | if (restart_syscall && !pt_regs_is_syscall(regs)) | |
544 | restart_syscall = 0; | |
545 | ||
1da177e4 | 546 | if (signr > 0) { |
28e61036 DM |
547 | if (restart_syscall) |
548 | syscall_restart(orig_i0, regs, &ka.sa); | |
ec98c6b9 DM |
549 | handle_signal(signr, &ka, &info, oldset, regs); |
550 | ||
2d7d5f05 DM |
551 | /* a signal was successfully delivered; the saved |
552 | * sigmask will have been stored in the signal frame, | |
553 | * and will be restored by sigreturn, so we can simply | |
554 | * clear the TIF_RESTORE_SIGMASK flag. | |
555 | */ | |
556 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) | |
557 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
b8b751be DM |
558 | |
559 | tracehook_signal_handler(signr, &info, &ka, regs, 0); | |
2d7d5f05 | 560 | return; |
1da177e4 | 561 | } |
28e61036 | 562 | if (restart_syscall && |
1da177e4 LT |
563 | (regs->u_regs[UREG_I0] == ERESTARTNOHAND || |
564 | regs->u_regs[UREG_I0] == ERESTARTSYS || | |
565 | regs->u_regs[UREG_I0] == ERESTARTNOINTR)) { | |
566 | /* replay the system call when we are done */ | |
28e61036 | 567 | regs->u_regs[UREG_I0] = orig_i0; |
1da177e4 LT |
568 | regs->pc -= 4; |
569 | regs->npc -= 4; | |
570 | } | |
28e61036 | 571 | if (restart_syscall && |
1da177e4 LT |
572 | regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) { |
573 | regs->u_regs[UREG_G1] = __NR_restart_syscall; | |
574 | regs->pc -= 4; | |
575 | regs->npc -= 4; | |
576 | } | |
2d7d5f05 DM |
577 | |
578 | /* if there's no signal to deliver, we just put the saved sigmask | |
579 | * back | |
580 | */ | |
581 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) { | |
582 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
583 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); | |
584 | } | |
1da177e4 LT |
585 | } |
586 | ||
5a157d5b DM |
587 | void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, |
588 | unsigned long thread_info_flags) | |
589 | { | |
590 | if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)) | |
591 | do_signal(regs, orig_i0); | |
592 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { | |
593 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
594 | tracehook_notify_resume(regs); | |
ee18d64c DH |
595 | if (current->replacement_session_keyring) |
596 | key_replace_session_keyring(); | |
5a157d5b DM |
597 | } |
598 | } | |
599 | ||
1da177e4 LT |
600 | asmlinkage int |
601 | do_sys_sigstack(struct sigstack __user *ssptr, struct sigstack __user *ossptr, | |
602 | unsigned long sp) | |
603 | { | |
604 | int ret = -EFAULT; | |
605 | ||
606 | /* First see if old state is wanted. */ | |
607 | if (ossptr) { | |
608 | if (put_user(current->sas_ss_sp + current->sas_ss_size, | |
609 | &ossptr->the_stack) || | |
610 | __put_user(on_sig_stack(sp), &ossptr->cur_status)) | |
611 | goto out; | |
612 | } | |
613 | ||
614 | /* Now see if we want to update the new state. */ | |
615 | if (ssptr) { | |
616 | char *ss_sp; | |
617 | ||
618 | if (get_user(ss_sp, &ssptr->the_stack)) | |
619 | goto out; | |
620 | /* If the current stack was set with sigaltstack, don't | |
621 | swap stacks while we are on it. */ | |
622 | ret = -EPERM; | |
623 | if (current->sas_ss_sp && on_sig_stack(sp)) | |
624 | goto out; | |
625 | ||
626 | /* Since we don't know the extent of the stack, and we don't | |
627 | track onstack-ness, but rather calculate it, we must | |
628 | presume a size. Ho hum this interface is lossy. */ | |
629 | current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ; | |
630 | current->sas_ss_size = SIGSTKSZ; | |
631 | } | |
632 | ret = 0; | |
633 | out: | |
634 | return ret; | |
635 | } |