Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/sh/kernel/signal.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | * | |
6 | * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson | |
7 | * | |
8 | * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima | |
9 | * | |
10 | */ | |
1da177e4 LT |
11 | #include <linux/sched.h> |
12 | #include <linux/mm.h> | |
13 | #include <linux/smp.h> | |
1da177e4 LT |
14 | #include <linux/kernel.h> |
15 | #include <linux/signal.h> | |
16 | #include <linux/errno.h> | |
17 | #include <linux/wait.h> | |
18 | #include <linux/ptrace.h> | |
19 | #include <linux/unistd.h> | |
20 | #include <linux/stddef.h> | |
21 | #include <linux/tty.h> | |
19f9a34f | 22 | #include <linux/elf.h> |
1da177e4 LT |
23 | #include <linux/personality.h> |
24 | #include <linux/binfmts.h> | |
7dfb7103 | 25 | #include <linux/freezer.h> |
b66d51cb | 26 | #include <linux/io.h> |
ab99c733 | 27 | #include <linux/tracehook.h> |
bd079997 | 28 | #include <asm/system.h> |
1da177e4 LT |
29 | #include <asm/ucontext.h> |
30 | #include <asm/uaccess.h> | |
31 | #include <asm/pgtable.h> | |
32 | #include <asm/cacheflush.h> | |
fa43972f | 33 | #include <asm/syscalls.h> |
9bbafce2 | 34 | #include <asm/fpu.h> |
1da177e4 | 35 | |
1da177e4 LT |
36 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) |
37 | ||
3bc24a1a PM |
38 | struct fdpic_func_descriptor { |
39 | unsigned long text; | |
40 | unsigned long GOT; | |
41 | }; | |
42 | ||
1da177e4 LT |
43 | /* |
44 | * Atomically swap in the new signal mask, and wait for a signal. | |
45 | */ | |
46 | asmlinkage int | |
47 | sys_sigsuspend(old_sigset_t mask, | |
48 | unsigned long r5, unsigned long r6, unsigned long r7, | |
f0bc814c | 49 | struct pt_regs __regs) |
1da177e4 | 50 | { |
1da177e4 LT |
51 | mask &= _BLOCKABLE; |
52 | spin_lock_irq(¤t->sighand->siglock); | |
9f23e7e9 | 53 | current->saved_sigmask = current->blocked; |
1da177e4 LT |
54 | siginitset(¤t->blocked, mask); |
55 | recalc_sigpending(); | |
56 | spin_unlock_irq(¤t->sighand->siglock); | |
57 | ||
9f23e7e9 PM |
58 | current->state = TASK_INTERRUPTIBLE; |
59 | schedule(); | |
60 | set_thread_flag(TIF_RESTORE_SIGMASK); | |
61 | return -ERESTARTNOHAND; | |
1da177e4 LT |
62 | } |
63 | ||
f0bc814c | 64 | asmlinkage int |
1da177e4 LT |
65 | sys_sigaction(int sig, const struct old_sigaction __user *act, |
66 | struct old_sigaction __user *oact) | |
67 | { | |
68 | struct k_sigaction new_ka, old_ka; | |
69 | int ret; | |
70 | ||
71 | if (act) { | |
72 | old_sigset_t mask; | |
73 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || | |
74 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | |
75 | __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) | |
76 | return -EFAULT; | |
77 | __get_user(new_ka.sa.sa_flags, &act->sa_flags); | |
78 | __get_user(mask, &act->sa_mask); | |
79 | siginitset(&new_ka.sa.sa_mask, mask); | |
80 | } | |
81 | ||
82 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
83 | ||
84 | if (!ret && oact) { | |
85 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
86 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | |
87 | __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) | |
88 | return -EFAULT; | |
89 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags); | |
90 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
91 | } | |
92 | ||
93 | return ret; | |
94 | } | |
95 | ||
96 | asmlinkage int | |
97 | sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, | |
98 | unsigned long r6, unsigned long r7, | |
f0bc814c | 99 | struct pt_regs __regs) |
1da177e4 | 100 | { |
f0bc814c SM |
101 | struct pt_regs *regs = RELOC_HIDE(&__regs, 0); |
102 | ||
103 | return do_sigaltstack(uss, uoss, regs->regs[15]); | |
1da177e4 LT |
104 | } |
105 | ||
106 | ||
107 | /* | |
108 | * Do a signal return; undo the signal stack. | |
109 | */ | |
110 | ||
111 | #define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */ | |
11cbb70e | 112 | #if defined(CONFIG_CPU_SH2) |
9d4436a6 YS |
113 | #define TRAP_NOARG 0xc320 /* Syscall w/no args (NR in R3) */ |
114 | #else | |
115 | #define TRAP_NOARG 0xc310 /* Syscall w/no args (NR in R3) */ | |
116 | #endif | |
1da177e4 LT |
117 | #define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */ |
118 | ||
119 | struct sigframe | |
120 | { | |
121 | struct sigcontext sc; | |
122 | unsigned long extramask[_NSIG_WORDS-1]; | |
123 | u16 retcode[8]; | |
124 | }; | |
125 | ||
126 | struct rt_sigframe | |
127 | { | |
128 | struct siginfo info; | |
129 | struct ucontext uc; | |
130 | u16 retcode[8]; | |
131 | }; | |
132 | ||
133 | #ifdef CONFIG_SH_FPU | |
134 | static inline int restore_sigcontext_fpu(struct sigcontext __user *sc) | |
135 | { | |
136 | struct task_struct *tsk = current; | |
137 | ||
11c19656 | 138 | if (!(current_cpu_data.flags & CPU_HAS_FPU)) |
1da177e4 LT |
139 | return 0; |
140 | ||
141 | set_used_math(); | |
142 | return __copy_from_user(&tsk->thread.fpu.hard, &sc->sc_fpregs[0], | |
143 | sizeof(long)*(16*2+2)); | |
144 | } | |
145 | ||
146 | static inline int save_sigcontext_fpu(struct sigcontext __user *sc, | |
147 | struct pt_regs *regs) | |
148 | { | |
149 | struct task_struct *tsk = current; | |
150 | ||
11c19656 | 151 | if (!(current_cpu_data.flags & CPU_HAS_FPU)) |
1da177e4 LT |
152 | return 0; |
153 | ||
154 | if (!used_math()) { | |
155 | __put_user(0, &sc->sc_ownedfp); | |
156 | return 0; | |
157 | } | |
158 | ||
159 | __put_user(1, &sc->sc_ownedfp); | |
160 | ||
161 | /* This will cause a "finit" to be triggered by the next | |
162 | attempted FPU operation by the 'current' process. | |
163 | */ | |
164 | clear_used_math(); | |
165 | ||
166 | unlazy_fpu(tsk, regs); | |
167 | return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.fpu.hard, | |
168 | sizeof(long)*(16*2+2)); | |
169 | } | |
170 | #endif /* CONFIG_SH_FPU */ | |
171 | ||
172 | static int | |
173 | restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p) | |
174 | { | |
175 | unsigned int err = 0; | |
176 | ||
177 | #define COPY(x) err |= __get_user(regs->x, &sc->sc_##x) | |
178 | COPY(regs[1]); | |
179 | COPY(regs[2]); COPY(regs[3]); | |
180 | COPY(regs[4]); COPY(regs[5]); | |
181 | COPY(regs[6]); COPY(regs[7]); | |
182 | COPY(regs[8]); COPY(regs[9]); | |
183 | COPY(regs[10]); COPY(regs[11]); | |
184 | COPY(regs[12]); COPY(regs[13]); | |
185 | COPY(regs[14]); COPY(regs[15]); | |
186 | COPY(gbr); COPY(mach); | |
187 | COPY(macl); COPY(pr); | |
188 | COPY(sr); COPY(pc); | |
189 | #undef COPY | |
190 | ||
191 | #ifdef CONFIG_SH_FPU | |
11c19656 | 192 | if (current_cpu_data.flags & CPU_HAS_FPU) { |
1da177e4 LT |
193 | int owned_fp; |
194 | struct task_struct *tsk = current; | |
195 | ||
196 | regs->sr |= SR_FD; /* Release FPU */ | |
197 | clear_fpu(tsk, regs); | |
198 | clear_used_math(); | |
199 | __get_user (owned_fp, &sc->sc_ownedfp); | |
200 | if (owned_fp) | |
201 | err |= restore_sigcontext_fpu(sc); | |
202 | } | |
203 | #endif | |
204 | ||
205 | regs->tra = -1; /* disable syscall checks */ | |
206 | err |= __get_user(*r0_p, &sc->sc_regs[0]); | |
207 | return err; | |
208 | } | |
209 | ||
210 | asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5, | |
211 | unsigned long r6, unsigned long r7, | |
f0bc814c | 212 | struct pt_regs __regs) |
1da177e4 | 213 | { |
f0bc814c SM |
214 | struct pt_regs *regs = RELOC_HIDE(&__regs, 0); |
215 | struct sigframe __user *frame = (struct sigframe __user *)regs->regs[15]; | |
1da177e4 LT |
216 | sigset_t set; |
217 | int r0; | |
218 | ||
1bec157a PM |
219 | /* Always make any pending restarted system calls return -EINTR */ |
220 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
221 | ||
1da177e4 LT |
222 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
223 | goto badframe; | |
224 | ||
225 | if (__get_user(set.sig[0], &frame->sc.oldmask) | |
226 | || (_NSIG_WORDS > 1 | |
227 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
228 | sizeof(frame->extramask)))) | |
229 | goto badframe; | |
230 | ||
231 | sigdelsetmask(&set, ~_BLOCKABLE); | |
232 | ||
233 | spin_lock_irq(¤t->sighand->siglock); | |
234 | current->blocked = set; | |
235 | recalc_sigpending(); | |
236 | spin_unlock_irq(¤t->sighand->siglock); | |
237 | ||
f0bc814c | 238 | if (restore_sigcontext(regs, &frame->sc, &r0)) |
1da177e4 LT |
239 | goto badframe; |
240 | return r0; | |
241 | ||
242 | badframe: | |
243 | force_sig(SIGSEGV, current); | |
244 | return 0; | |
245 | } | |
246 | ||
247 | asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5, | |
248 | unsigned long r6, unsigned long r7, | |
f0bc814c | 249 | struct pt_regs __regs) |
1da177e4 | 250 | { |
f0bc814c SM |
251 | struct pt_regs *regs = RELOC_HIDE(&__regs, 0); |
252 | struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->regs[15]; | |
1da177e4 | 253 | sigset_t set; |
1da177e4 LT |
254 | int r0; |
255 | ||
1bec157a PM |
256 | /* Always make any pending restarted system calls return -EINTR */ |
257 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
258 | ||
1da177e4 LT |
259 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
260 | goto badframe; | |
261 | ||
262 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
263 | goto badframe; | |
264 | ||
265 | sigdelsetmask(&set, ~_BLOCKABLE); | |
266 | spin_lock_irq(¤t->sighand->siglock); | |
267 | current->blocked = set; | |
268 | recalc_sigpending(); | |
269 | spin_unlock_irq(¤t->sighand->siglock); | |
270 | ||
f0bc814c | 271 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0)) |
1da177e4 LT |
272 | goto badframe; |
273 | ||
fa43972f PM |
274 | if (do_sigaltstack(&frame->uc.uc_stack, NULL, |
275 | regs->regs[15]) == -EFAULT) | |
1da177e4 | 276 | goto badframe; |
1da177e4 LT |
277 | |
278 | return r0; | |
279 | ||
280 | badframe: | |
281 | force_sig(SIGSEGV, current); | |
282 | return 0; | |
3aeb884b | 283 | } |
1da177e4 LT |
284 | |
285 | /* | |
286 | * Set up a signal frame. | |
287 | */ | |
288 | ||
289 | static int | |
290 | setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, | |
291 | unsigned long mask) | |
292 | { | |
293 | int err = 0; | |
294 | ||
295 | #define COPY(x) err |= __put_user(regs->x, &sc->sc_##x) | |
296 | COPY(regs[0]); COPY(regs[1]); | |
297 | COPY(regs[2]); COPY(regs[3]); | |
298 | COPY(regs[4]); COPY(regs[5]); | |
299 | COPY(regs[6]); COPY(regs[7]); | |
300 | COPY(regs[8]); COPY(regs[9]); | |
301 | COPY(regs[10]); COPY(regs[11]); | |
302 | COPY(regs[12]); COPY(regs[13]); | |
303 | COPY(regs[14]); COPY(regs[15]); | |
304 | COPY(gbr); COPY(mach); | |
305 | COPY(macl); COPY(pr); | |
306 | COPY(sr); COPY(pc); | |
307 | #undef COPY | |
308 | ||
309 | #ifdef CONFIG_SH_FPU | |
310 | err |= save_sigcontext_fpu(sc, regs); | |
311 | #endif | |
312 | ||
313 | /* non-iBCS2 extensions.. */ | |
314 | err |= __put_user(mask, &sc->oldmask); | |
315 | ||
316 | return err; | |
317 | } | |
318 | ||
319 | /* | |
320 | * Determine which stack to use.. | |
321 | */ | |
322 | static inline void __user * | |
323 | get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) | |
324 | { | |
325 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
326 | if (sas_ss_flags(sp) == 0) | |
327 | sp = current->sas_ss_sp + current->sas_ss_size; | |
328 | } | |
329 | ||
330 | return (void __user *)((sp - frame_size) & -8ul); | |
331 | } | |
332 | ||
19f9a34f PM |
333 | /* These symbols are defined with the addresses in the vsyscall page. |
334 | See vsyscall-trapa.S. */ | |
335 | extern void __user __kernel_sigreturn; | |
336 | extern void __user __kernel_rt_sigreturn; | |
337 | ||
9f23e7e9 | 338 | static int setup_frame(int sig, struct k_sigaction *ka, |
1da177e4 LT |
339 | sigset_t *set, struct pt_regs *regs) |
340 | { | |
341 | struct sigframe __user *frame; | |
342 | int err = 0; | |
343 | int signal; | |
344 | ||
345 | frame = get_sigframe(ka, regs->regs[15], sizeof(*frame)); | |
346 | ||
347 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
348 | goto give_sigsegv; | |
349 | ||
350 | signal = current_thread_info()->exec_domain | |
351 | && current_thread_info()->exec_domain->signal_invmap | |
352 | && sig < 32 | |
353 | ? current_thread_info()->exec_domain->signal_invmap[sig] | |
354 | : sig; | |
355 | ||
356 | err |= setup_sigcontext(&frame->sc, regs, set->sig[0]); | |
357 | ||
9f23e7e9 | 358 | if (_NSIG_WORDS > 1) |
1da177e4 LT |
359 | err |= __copy_to_user(frame->extramask, &set->sig[1], |
360 | sizeof(frame->extramask)); | |
1da177e4 LT |
361 | |
362 | /* Set up to return from userspace. If provided, use a stub | |
363 | already in userspace. */ | |
364 | if (ka->sa.sa_flags & SA_RESTORER) { | |
365 | regs->pr = (unsigned long) ka->sa.sa_restorer; | |
19f9a34f PM |
366 | #ifdef CONFIG_VSYSCALL |
367 | } else if (likely(current->mm->context.vdso)) { | |
368 | regs->pr = VDSO_SYM(&__kernel_sigreturn); | |
369 | #endif | |
1da177e4 LT |
370 | } else { |
371 | /* Generate return code (system call to sigreturn) */ | |
372 | err |= __put_user(MOVW(7), &frame->retcode[0]); | |
9d4436a6 | 373 | err |= __put_user(TRAP_NOARG, &frame->retcode[1]); |
1da177e4 LT |
374 | err |= __put_user(OR_R0_R0, &frame->retcode[2]); |
375 | err |= __put_user(OR_R0_R0, &frame->retcode[3]); | |
376 | err |= __put_user(OR_R0_R0, &frame->retcode[4]); | |
377 | err |= __put_user(OR_R0_R0, &frame->retcode[5]); | |
378 | err |= __put_user(OR_R0_R0, &frame->retcode[6]); | |
379 | err |= __put_user((__NR_sigreturn), &frame->retcode[7]); | |
380 | regs->pr = (unsigned long) frame->retcode; | |
f2fb4e4f | 381 | flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode)); |
1da177e4 LT |
382 | } |
383 | ||
384 | if (err) | |
385 | goto give_sigsegv; | |
386 | ||
387 | /* Set up registers for signal handler */ | |
388 | regs->regs[15] = (unsigned long) frame; | |
389 | regs->regs[4] = signal; /* Arg for signal handler */ | |
390 | regs->regs[5] = 0; | |
391 | regs->regs[6] = (unsigned long) &frame->sc; | |
3bc24a1a PM |
392 | |
393 | if (current->personality & FDPIC_FUNCPTRS) { | |
394 | struct fdpic_func_descriptor __user *funcptr = | |
395 | (struct fdpic_func_descriptor __user *)ka->sa.sa_handler; | |
396 | ||
397 | __get_user(regs->pc, &funcptr->text); | |
398 | __get_user(regs->regs[12], &funcptr->GOT); | |
399 | } else | |
400 | regs->pc = (unsigned long)ka->sa.sa_handler; | |
1da177e4 LT |
401 | |
402 | set_fs(USER_DS); | |
403 | ||
9f23e7e9 | 404 | pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", |
19c5870c | 405 | current->comm, task_pid_nr(current), frame, regs->pc, regs->pr); |
1da177e4 | 406 | |
9f23e7e9 | 407 | return 0; |
1da177e4 LT |
408 | |
409 | give_sigsegv: | |
410 | force_sigsegv(sig, current); | |
9f23e7e9 | 411 | return -EFAULT; |
1da177e4 LT |
412 | } |
413 | ||
9f23e7e9 | 414 | static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
1da177e4 LT |
415 | sigset_t *set, struct pt_regs *regs) |
416 | { | |
417 | struct rt_sigframe __user *frame; | |
418 | int err = 0; | |
419 | int signal; | |
420 | ||
421 | frame = get_sigframe(ka, regs->regs[15], sizeof(*frame)); | |
422 | ||
423 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
424 | goto give_sigsegv; | |
425 | ||
426 | signal = current_thread_info()->exec_domain | |
427 | && current_thread_info()->exec_domain->signal_invmap | |
428 | && sig < 32 | |
429 | ? current_thread_info()->exec_domain->signal_invmap[sig] | |
430 | : sig; | |
431 | ||
432 | err |= copy_siginfo_to_user(&frame->info, info); | |
433 | ||
434 | /* Create the ucontext. */ | |
435 | err |= __put_user(0, &frame->uc.uc_flags); | |
fa43972f | 436 | err |= __put_user(NULL, &frame->uc.uc_link); |
1da177e4 LT |
437 | err |= __put_user((void *)current->sas_ss_sp, |
438 | &frame->uc.uc_stack.ss_sp); | |
439 | err |= __put_user(sas_ss_flags(regs->regs[15]), | |
440 | &frame->uc.uc_stack.ss_flags); | |
441 | err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
442 | err |= setup_sigcontext(&frame->uc.uc_mcontext, | |
443 | regs, set->sig[0]); | |
444 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
445 | ||
446 | /* Set up to return from userspace. If provided, use a stub | |
447 | already in userspace. */ | |
448 | if (ka->sa.sa_flags & SA_RESTORER) { | |
449 | regs->pr = (unsigned long) ka->sa.sa_restorer; | |
19f9a34f PM |
450 | #ifdef CONFIG_VSYSCALL |
451 | } else if (likely(current->mm->context.vdso)) { | |
452 | regs->pr = VDSO_SYM(&__kernel_rt_sigreturn); | |
453 | #endif | |
1da177e4 LT |
454 | } else { |
455 | /* Generate return code (system call to rt_sigreturn) */ | |
456 | err |= __put_user(MOVW(7), &frame->retcode[0]); | |
9d4436a6 | 457 | err |= __put_user(TRAP_NOARG, &frame->retcode[1]); |
1da177e4 LT |
458 | err |= __put_user(OR_R0_R0, &frame->retcode[2]); |
459 | err |= __put_user(OR_R0_R0, &frame->retcode[3]); | |
460 | err |= __put_user(OR_R0_R0, &frame->retcode[4]); | |
461 | err |= __put_user(OR_R0_R0, &frame->retcode[5]); | |
462 | err |= __put_user(OR_R0_R0, &frame->retcode[6]); | |
463 | err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]); | |
464 | regs->pr = (unsigned long) frame->retcode; | |
465 | } | |
466 | ||
467 | if (err) | |
468 | goto give_sigsegv; | |
469 | ||
470 | /* Set up registers for signal handler */ | |
471 | regs->regs[15] = (unsigned long) frame; | |
472 | regs->regs[4] = signal; /* Arg for signal handler */ | |
473 | regs->regs[5] = (unsigned long) &frame->info; | |
474 | regs->regs[6] = (unsigned long) &frame->uc; | |
3bc24a1a PM |
475 | |
476 | if (current->personality & FDPIC_FUNCPTRS) { | |
477 | struct fdpic_func_descriptor __user *funcptr = | |
478 | (struct fdpic_func_descriptor __user *)ka->sa.sa_handler; | |
479 | ||
480 | __get_user(regs->pc, &funcptr->text); | |
481 | __get_user(regs->regs[12], &funcptr->GOT); | |
482 | } else | |
483 | regs->pc = (unsigned long)ka->sa.sa_handler; | |
1da177e4 LT |
484 | |
485 | set_fs(USER_DS); | |
486 | ||
9f23e7e9 | 487 | pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", |
19c5870c | 488 | current->comm, task_pid_nr(current), frame, regs->pc, regs->pr); |
1da177e4 | 489 | |
09b5a10c | 490 | flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode)); |
9f23e7e9 PM |
491 | |
492 | return 0; | |
1da177e4 LT |
493 | |
494 | give_sigsegv: | |
495 | force_sigsegv(sig, current); | |
9f23e7e9 | 496 | return -EFAULT; |
1da177e4 LT |
497 | } |
498 | ||
f8b890ab PM |
499 | static inline void |
500 | handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs, | |
501 | struct sigaction *sa) | |
502 | { | |
503 | /* If we're not from a syscall, bail out */ | |
504 | if (regs->tra < 0) | |
505 | return; | |
506 | ||
507 | /* check for system call restart.. */ | |
508 | switch (regs->regs[0]) { | |
509 | case -ERESTART_RESTARTBLOCK: | |
510 | case -ERESTARTNOHAND: | |
511 | no_system_call_restart: | |
512 | regs->regs[0] = -EINTR; | |
513 | regs->sr |= 1; | |
514 | break; | |
515 | ||
516 | case -ERESTARTSYS: | |
517 | if (!(sa->sa_flags & SA_RESTART)) | |
518 | goto no_system_call_restart; | |
519 | /* fallthrough */ | |
520 | case -ERESTARTNOINTR: | |
521 | regs->regs[0] = save_r0; | |
522 | regs->pc -= instruction_size(ctrl_inw(regs->pc - 4)); | |
523 | break; | |
524 | } | |
525 | } | |
526 | ||
1da177e4 LT |
527 | /* |
528 | * OK, we're invoking a handler | |
529 | */ | |
9f23e7e9 | 530 | static int |
1da177e4 | 531 | handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info, |
69a33147 | 532 | sigset_t *oldset, struct pt_regs *regs, unsigned int save_r0) |
1da177e4 | 533 | { |
9f23e7e9 PM |
534 | int ret; |
535 | ||
1da177e4 LT |
536 | /* Set up the stack frame */ |
537 | if (ka->sa.sa_flags & SA_SIGINFO) | |
9f23e7e9 | 538 | ret = setup_rt_frame(sig, ka, info, oldset, regs); |
1da177e4 | 539 | else |
9f23e7e9 | 540 | ret = setup_frame(sig, ka, oldset, regs); |
1da177e4 LT |
541 | |
542 | if (ka->sa.sa_flags & SA_ONESHOT) | |
543 | ka->sa.sa_handler = SIG_DFL; | |
544 | ||
9f23e7e9 PM |
545 | if (ret == 0) { |
546 | spin_lock_irq(¤t->sighand->siglock); | |
547 | sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); | |
548 | if (!(ka->sa.sa_flags & SA_NODEFER)) | |
549 | sigaddset(¤t->blocked,sig); | |
550 | recalc_sigpending(); | |
551 | spin_unlock_irq(¤t->sighand->siglock); | |
552 | } | |
553 | ||
554 | return ret; | |
1da177e4 LT |
555 | } |
556 | ||
557 | /* | |
558 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
559 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
560 | * mistake. | |
561 | * | |
562 | * Note that we go through the signals twice: once to check the signals that | |
563 | * the kernel can handle, and then we build all the user-level signal handling | |
564 | * stack-frames in one go after that. | |
565 | */ | |
9f23e7e9 | 566 | static void do_signal(struct pt_regs *regs, unsigned int save_r0) |
1da177e4 LT |
567 | { |
568 | siginfo_t info; | |
569 | int signr; | |
570 | struct k_sigaction ka; | |
9f23e7e9 | 571 | sigset_t *oldset; |
1da177e4 LT |
572 | |
573 | /* | |
574 | * We want the common case to go fast, which | |
575 | * is why we may in certain cases get here from | |
576 | * kernel mode. Just return without doing anything | |
577 | * if so. | |
578 | */ | |
579 | if (!user_mode(regs)) | |
9f23e7e9 | 580 | return; |
1da177e4 | 581 | |
0e6c1f5f | 582 | if (try_to_freeze()) |
1da177e4 LT |
583 | goto no_signal; |
584 | ||
9f23e7e9 PM |
585 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) |
586 | oldset = ¤t->saved_sigmask; | |
587 | else | |
1da177e4 LT |
588 | oldset = ¤t->blocked; |
589 | ||
590 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
591 | if (signr > 0) { | |
f8b890ab PM |
592 | if (regs->sr & 1) |
593 | handle_syscall_restart(save_r0, regs, &ka.sa); | |
594 | ||
1da177e4 | 595 | /* Whee! Actually deliver the signal. */ |
3aeb884b PM |
596 | if (handle_signal(signr, &ka, &info, oldset, |
597 | regs, save_r0) == 0) { | |
9f23e7e9 PM |
598 | /* a signal was successfully delivered; the saved |
599 | * sigmask will have been stored in the signal frame, | |
600 | * and will be restored by sigreturn, so we can simply | |
601 | * clear the TIF_RESTORE_SIGMASK flag */ | |
602 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) | |
603 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
ab99c733 PM |
604 | |
605 | tracehook_signal_handler(signr, &info, &ka, regs, | |
606 | test_thread_flag(TIF_SINGLESTEP)); | |
9f23e7e9 | 607 | } |
c8bfa1fd RS |
608 | |
609 | return; | |
1da177e4 LT |
610 | } |
611 | ||
ab99c733 | 612 | no_signal: |
1da177e4 LT |
613 | /* Did we come from a system call? */ |
614 | if (regs->tra >= 0) { | |
615 | /* Restart the system call - no handlers present */ | |
616 | if (regs->regs[0] == -ERESTARTNOHAND || | |
617 | regs->regs[0] == -ERESTARTSYS || | |
0b892935 | 618 | regs->regs[0] == -ERESTARTNOINTR) { |
c8bfa1fd | 619 | regs->regs[0] = save_r0; |
53f983a9 | 620 | regs->pc -= instruction_size(ctrl_inw(regs->pc - 4)); |
0b892935 | 621 | } else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) { |
53f983a9 | 622 | regs->pc -= instruction_size(ctrl_inw(regs->pc - 4)); |
0b892935 | 623 | regs->regs[3] = __NR_restart_syscall; |
1da177e4 LT |
624 | } |
625 | } | |
9f23e7e9 PM |
626 | |
627 | /* if there's no signal to deliver, we just put the saved sigmask | |
628 | * back */ | |
629 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) { | |
630 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
631 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); | |
632 | } | |
633 | } | |
634 | ||
635 | asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0, | |
ab99c733 | 636 | unsigned long thread_info_flags) |
9f23e7e9 PM |
637 | { |
638 | /* deal with pending signal delivery */ | |
ab99c733 | 639 | if (thread_info_flags & _TIF_SIGPENDING) |
9f23e7e9 | 640 | do_signal(regs, save_r0); |
ab99c733 PM |
641 | |
642 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { | |
643 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
644 | tracehook_notify_resume(regs); | |
645 | } | |
1da177e4 | 646 | } |