2 * linux/arch/sh/kernel/signal.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
6 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
8 * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
11 #include <linux/sched.h>
13 #include <linux/smp.h>
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>
22 #include <linux/elf.h>
23 #include <linux/personality.h>
24 #include <linux/binfmts.h>
25 #include <linux/freezer.h>
27 #include <linux/tracehook.h>
28 #include <asm/ucontext.h>
29 #include <asm/uaccess.h>
30 #include <asm/pgtable.h>
31 #include <asm/cacheflush.h>
32 #include <asm/syscalls.h>
35 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
37 struct fdpic_func_descriptor {
43 * The following define adds a 64 byte gap between the signal
44 * stack frame and previous contents of the stack. This allows
45 * frame unwinding in a function epilogue but only if a frame
46 * pointer is used in the function. This is necessary because
47 * current gcc compilers (<4.3) do not generate unwind info on
48 * SH for function epilogues.
50 #define UNWINDGUARD 64
53 * Atomically swap in the new signal mask, and wait for a signal.
56 sys_sigsuspend(old_sigset_t mask,
57 unsigned long r5, unsigned long r6, unsigned long r7,
58 struct pt_regs __regs)
62 current->saved_sigmask = current->blocked;
65 siginitset(&blocked, mask);
66 set_current_blocked(&blocked);
68 current->state = TASK_INTERRUPTIBLE;
70 set_restore_sigmask();
72 return -ERESTARTNOHAND;
76 sys_sigaction(int sig, const struct old_sigaction __user *act,
77 struct old_sigaction __user *oact)
79 struct k_sigaction new_ka, old_ka;
84 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
85 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
86 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
88 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
89 __get_user(mask, &act->sa_mask);
90 siginitset(&new_ka.sa.sa_mask, mask);
93 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
96 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
97 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
98 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
100 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
101 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
108 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
109 unsigned long r6, unsigned long r7,
110 struct pt_regs __regs)
112 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
114 return do_sigaltstack(uss, uoss, regs->regs[15]);
119 * Do a signal return; undo the signal stack.
122 #define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */
123 #if defined(CONFIG_CPU_SH2)
124 #define TRAP_NOARG 0xc320 /* Syscall w/no args (NR in R3) */
126 #define TRAP_NOARG 0xc310 /* Syscall w/no args (NR in R3) */
128 #define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */
132 struct sigcontext sc;
133 unsigned long extramask[_NSIG_WORDS-1];
145 static inline int restore_sigcontext_fpu(struct sigcontext __user *sc)
147 struct task_struct *tsk = current;
149 if (!(boot_cpu_data.flags & CPU_HAS_FPU))
153 return __copy_from_user(&tsk->thread.xstate->hardfpu, &sc->sc_fpregs[0],
154 sizeof(long)*(16*2+2));
157 static inline int save_sigcontext_fpu(struct sigcontext __user *sc,
158 struct pt_regs *regs)
160 struct task_struct *tsk = current;
162 if (!(boot_cpu_data.flags & CPU_HAS_FPU))
166 __put_user(0, &sc->sc_ownedfp);
170 __put_user(1, &sc->sc_ownedfp);
172 /* This will cause a "finit" to be triggered by the next
173 attempted FPU operation by the 'current' process.
177 unlazy_fpu(tsk, regs);
178 return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.xstate->hardfpu,
179 sizeof(long)*(16*2+2));
181 #endif /* CONFIG_SH_FPU */
184 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p)
186 unsigned int err = 0;
188 #define COPY(x) err |= __get_user(regs->x, &sc->sc_##x)
190 COPY(regs[2]); COPY(regs[3]);
191 COPY(regs[4]); COPY(regs[5]);
192 COPY(regs[6]); COPY(regs[7]);
193 COPY(regs[8]); COPY(regs[9]);
194 COPY(regs[10]); COPY(regs[11]);
195 COPY(regs[12]); COPY(regs[13]);
196 COPY(regs[14]); COPY(regs[15]);
197 COPY(gbr); COPY(mach);
198 COPY(macl); COPY(pr);
203 if (boot_cpu_data.flags & CPU_HAS_FPU) {
205 struct task_struct *tsk = current;
207 regs->sr |= SR_FD; /* Release FPU */
208 clear_fpu(tsk, regs);
210 __get_user (owned_fp, &sc->sc_ownedfp);
212 err |= restore_sigcontext_fpu(sc);
216 regs->tra = -1; /* disable syscall checks */
217 err |= __get_user(*r0_p, &sc->sc_regs[0]);
221 asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5,
222 unsigned long r6, unsigned long r7,
223 struct pt_regs __regs)
225 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
226 struct sigframe __user *frame = (struct sigframe __user *)regs->regs[15];
230 /* Always make any pending restarted system calls return -EINTR */
231 current_thread_info()->restart_block.fn = do_no_restart_syscall;
233 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
236 if (__get_user(set.sig[0], &frame->sc.oldmask)
238 && __copy_from_user(&set.sig[1], &frame->extramask,
239 sizeof(frame->extramask))))
242 sigdelsetmask(&set, ~_BLOCKABLE);
243 set_current_blocked(&set);
245 if (restore_sigcontext(regs, &frame->sc, &r0))
250 force_sig(SIGSEGV, current);
254 asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5,
255 unsigned long r6, unsigned long r7,
256 struct pt_regs __regs)
258 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
259 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->regs[15];
263 /* Always make any pending restarted system calls return -EINTR */
264 current_thread_info()->restart_block.fn = do_no_restart_syscall;
266 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
269 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
272 sigdelsetmask(&set, ~_BLOCKABLE);
273 set_current_blocked(&set);
275 if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
278 if (do_sigaltstack(&frame->uc.uc_stack, NULL,
279 regs->regs[15]) == -EFAULT)
285 force_sig(SIGSEGV, current);
290 * Set up a signal frame.
294 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
299 #define COPY(x) err |= __put_user(regs->x, &sc->sc_##x)
300 COPY(regs[0]); COPY(regs[1]);
301 COPY(regs[2]); COPY(regs[3]);
302 COPY(regs[4]); COPY(regs[5]);
303 COPY(regs[6]); COPY(regs[7]);
304 COPY(regs[8]); COPY(regs[9]);
305 COPY(regs[10]); COPY(regs[11]);
306 COPY(regs[12]); COPY(regs[13]);
307 COPY(regs[14]); COPY(regs[15]);
308 COPY(gbr); COPY(mach);
309 COPY(macl); COPY(pr);
314 err |= save_sigcontext_fpu(sc, regs);
317 /* non-iBCS2 extensions.. */
318 err |= __put_user(mask, &sc->oldmask);
324 * Determine which stack to use..
326 static inline void __user *
327 get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
329 if (ka->sa.sa_flags & SA_ONSTACK) {
330 if (sas_ss_flags(sp) == 0)
331 sp = current->sas_ss_sp + current->sas_ss_size;
334 return (void __user *)((sp - (frame_size+UNWINDGUARD)) & -8ul);
337 /* These symbols are defined with the addresses in the vsyscall page.
338 See vsyscall-trapa.S. */
339 extern void __kernel_sigreturn(void);
340 extern void __kernel_rt_sigreturn(void);
342 static int setup_frame(int sig, struct k_sigaction *ka,
343 sigset_t *set, struct pt_regs *regs)
345 struct sigframe __user *frame;
349 frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
351 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
354 signal = current_thread_info()->exec_domain
355 && current_thread_info()->exec_domain->signal_invmap
357 ? current_thread_info()->exec_domain->signal_invmap[sig]
360 err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
363 err |= __copy_to_user(frame->extramask, &set->sig[1],
364 sizeof(frame->extramask));
366 /* Set up to return from userspace. If provided, use a stub
367 already in userspace. */
368 if (ka->sa.sa_flags & SA_RESTORER) {
369 regs->pr = (unsigned long) ka->sa.sa_restorer;
370 #ifdef CONFIG_VSYSCALL
371 } else if (likely(current->mm->context.vdso)) {
372 regs->pr = VDSO_SYM(&__kernel_sigreturn);
375 /* Generate return code (system call to sigreturn) */
376 err |= __put_user(MOVW(7), &frame->retcode[0]);
377 err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
378 err |= __put_user(OR_R0_R0, &frame->retcode[2]);
379 err |= __put_user(OR_R0_R0, &frame->retcode[3]);
380 err |= __put_user(OR_R0_R0, &frame->retcode[4]);
381 err |= __put_user(OR_R0_R0, &frame->retcode[5]);
382 err |= __put_user(OR_R0_R0, &frame->retcode[6]);
383 err |= __put_user((__NR_sigreturn), &frame->retcode[7]);
384 regs->pr = (unsigned long) frame->retcode;
385 flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
391 /* Set up registers for signal handler */
392 regs->regs[15] = (unsigned long) frame;
393 regs->regs[4] = signal; /* Arg for signal handler */
395 regs->regs[6] = (unsigned long) &frame->sc;
397 if (current->personality & FDPIC_FUNCPTRS) {
398 struct fdpic_func_descriptor __user *funcptr =
399 (struct fdpic_func_descriptor __user *)ka->sa.sa_handler;
401 __get_user(regs->pc, &funcptr->text);
402 __get_user(regs->regs[12], &funcptr->GOT);
404 regs->pc = (unsigned long)ka->sa.sa_handler;
408 pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
409 current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
414 force_sigsegv(sig, current);
418 static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
419 sigset_t *set, struct pt_regs *regs)
421 struct rt_sigframe __user *frame;
425 frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
427 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
430 signal = current_thread_info()->exec_domain
431 && current_thread_info()->exec_domain->signal_invmap
433 ? current_thread_info()->exec_domain->signal_invmap[sig]
436 err |= copy_siginfo_to_user(&frame->info, info);
438 /* Create the ucontext. */
439 err |= __put_user(0, &frame->uc.uc_flags);
440 err |= __put_user(NULL, &frame->uc.uc_link);
441 err |= __put_user((void *)current->sas_ss_sp,
442 &frame->uc.uc_stack.ss_sp);
443 err |= __put_user(sas_ss_flags(regs->regs[15]),
444 &frame->uc.uc_stack.ss_flags);
445 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
446 err |= setup_sigcontext(&frame->uc.uc_mcontext,
448 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
450 /* Set up to return from userspace. If provided, use a stub
451 already in userspace. */
452 if (ka->sa.sa_flags & SA_RESTORER) {
453 regs->pr = (unsigned long) ka->sa.sa_restorer;
454 #ifdef CONFIG_VSYSCALL
455 } else if (likely(current->mm->context.vdso)) {
456 regs->pr = VDSO_SYM(&__kernel_rt_sigreturn);
459 /* Generate return code (system call to rt_sigreturn) */
460 err |= __put_user(MOVW(7), &frame->retcode[0]);
461 err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
462 err |= __put_user(OR_R0_R0, &frame->retcode[2]);
463 err |= __put_user(OR_R0_R0, &frame->retcode[3]);
464 err |= __put_user(OR_R0_R0, &frame->retcode[4]);
465 err |= __put_user(OR_R0_R0, &frame->retcode[5]);
466 err |= __put_user(OR_R0_R0, &frame->retcode[6]);
467 err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]);
468 regs->pr = (unsigned long) frame->retcode;
469 flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
475 /* Set up registers for signal handler */
476 regs->regs[15] = (unsigned long) frame;
477 regs->regs[4] = signal; /* Arg for signal handler */
478 regs->regs[5] = (unsigned long) &frame->info;
479 regs->regs[6] = (unsigned long) &frame->uc;
481 if (current->personality & FDPIC_FUNCPTRS) {
482 struct fdpic_func_descriptor __user *funcptr =
483 (struct fdpic_func_descriptor __user *)ka->sa.sa_handler;
485 __get_user(regs->pc, &funcptr->text);
486 __get_user(regs->regs[12], &funcptr->GOT);
488 regs->pc = (unsigned long)ka->sa.sa_handler;
492 pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
493 current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
498 force_sigsegv(sig, current);
503 handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs,
504 struct sigaction *sa)
506 /* If we're not from a syscall, bail out */
510 /* check for system call restart.. */
511 switch (regs->regs[0]) {
512 case -ERESTART_RESTARTBLOCK:
513 case -ERESTARTNOHAND:
514 no_system_call_restart:
515 regs->regs[0] = -EINTR;
519 if (!(sa->sa_flags & SA_RESTART))
520 goto no_system_call_restart;
522 case -ERESTARTNOINTR:
523 regs->regs[0] = save_r0;
524 regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
530 * OK, we're invoking a handler
533 handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
534 sigset_t *oldset, struct pt_regs *regs, unsigned int save_r0)
538 /* Set up the stack frame */
539 if (ka->sa.sa_flags & SA_SIGINFO)
540 ret = setup_rt_frame(sig, ka, info, oldset, regs);
542 ret = setup_frame(sig, ka, oldset, regs);
545 block_sigmask(ka, sig);
551 * Note that 'init' is a special process: it doesn't get signals it doesn't
552 * want to handle. Thus you cannot kill init even with a SIGKILL even by
555 * Note that we go through the signals twice: once to check the signals that
556 * the kernel can handle, and then we build all the user-level signal handling
557 * stack-frames in one go after that.
559 static void do_signal(struct pt_regs *regs, unsigned int save_r0)
563 struct k_sigaction ka;
567 * We want the common case to go fast, which
568 * is why we may in certain cases get here from
569 * kernel mode. Just return without doing anything
572 if (!user_mode(regs))
575 if (current_thread_info()->status & TS_RESTORE_SIGMASK)
576 oldset = ¤t->saved_sigmask;
578 oldset = ¤t->blocked;
580 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
582 handle_syscall_restart(save_r0, regs, &ka.sa);
584 /* Whee! Actually deliver the signal. */
585 if (handle_signal(signr, &ka, &info, oldset,
586 regs, save_r0) == 0) {
588 * A signal was successfully delivered; the saved
589 * sigmask will have been stored in the signal frame,
590 * and will be restored by sigreturn, so we can simply
591 * clear the TS_RESTORE_SIGMASK flag
593 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
595 tracehook_signal_handler(signr, &info, &ka, regs,
596 test_thread_flag(TIF_SINGLESTEP));
602 /* Did we come from a system call? */
603 if (regs->tra >= 0) {
604 /* Restart the system call - no handlers present */
605 if (regs->regs[0] == -ERESTARTNOHAND ||
606 regs->regs[0] == -ERESTARTSYS ||
607 regs->regs[0] == -ERESTARTNOINTR) {
608 regs->regs[0] = save_r0;
609 regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
610 } else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) {
611 regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
612 regs->regs[3] = __NR_restart_syscall;
617 * If there's no signal to deliver, we just put the saved sigmask
620 if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
621 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
622 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
626 asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
627 unsigned long thread_info_flags)
629 /* deal with pending signal delivery */
630 if (thread_info_flags & _TIF_SIGPENDING)
631 do_signal(regs, save_r0);
633 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
634 clear_thread_flag(TIF_NOTIFY_RESUME);
635 tracehook_notify_resume(regs);
636 if (current->replacement_session_keyring)
637 key_replace_session_keyring();