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)
61 spin_lock_irq(¤t->sighand->siglock);
62 current->saved_sigmask = current->blocked;
63 siginitset(¤t->blocked, mask);
65 spin_unlock_irq(¤t->sighand->siglock);
67 current->state = TASK_INTERRUPTIBLE;
69 set_restore_sigmask();
71 return -ERESTARTNOHAND;
75 sys_sigaction(int sig, const struct old_sigaction __user *act,
76 struct old_sigaction __user *oact)
78 struct k_sigaction new_ka, old_ka;
83 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
84 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
85 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
87 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
88 __get_user(mask, &act->sa_mask);
89 siginitset(&new_ka.sa.sa_mask, mask);
92 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
95 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
96 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
97 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
99 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
100 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
107 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
108 unsigned long r6, unsigned long r7,
109 struct pt_regs __regs)
111 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
113 return do_sigaltstack(uss, uoss, regs->regs[15]);
118 * Do a signal return; undo the signal stack.
121 #define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */
122 #if defined(CONFIG_CPU_SH2)
123 #define TRAP_NOARG 0xc320 /* Syscall w/no args (NR in R3) */
125 #define TRAP_NOARG 0xc310 /* Syscall w/no args (NR in R3) */
127 #define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */
131 struct sigcontext sc;
132 unsigned long extramask[_NSIG_WORDS-1];
144 static inline int restore_sigcontext_fpu(struct sigcontext __user *sc)
146 struct task_struct *tsk = current;
148 if (!(boot_cpu_data.flags & CPU_HAS_FPU))
152 return __copy_from_user(&tsk->thread.xstate->hardfpu, &sc->sc_fpregs[0],
153 sizeof(long)*(16*2+2));
156 static inline int save_sigcontext_fpu(struct sigcontext __user *sc,
157 struct pt_regs *regs)
159 struct task_struct *tsk = current;
161 if (!(boot_cpu_data.flags & CPU_HAS_FPU))
165 __put_user(0, &sc->sc_ownedfp);
169 __put_user(1, &sc->sc_ownedfp);
171 /* This will cause a "finit" to be triggered by the next
172 attempted FPU operation by the 'current' process.
176 unlazy_fpu(tsk, regs);
177 return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.xstate->hardfpu,
178 sizeof(long)*(16*2+2));
180 #endif /* CONFIG_SH_FPU */
183 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p)
185 unsigned int err = 0;
187 #define COPY(x) err |= __get_user(regs->x, &sc->sc_##x)
189 COPY(regs[2]); COPY(regs[3]);
190 COPY(regs[4]); COPY(regs[5]);
191 COPY(regs[6]); COPY(regs[7]);
192 COPY(regs[8]); COPY(regs[9]);
193 COPY(regs[10]); COPY(regs[11]);
194 COPY(regs[12]); COPY(regs[13]);
195 COPY(regs[14]); COPY(regs[15]);
196 COPY(gbr); COPY(mach);
197 COPY(macl); COPY(pr);
202 if (boot_cpu_data.flags & CPU_HAS_FPU) {
204 struct task_struct *tsk = current;
206 regs->sr |= SR_FD; /* Release FPU */
207 clear_fpu(tsk, regs);
209 __get_user (owned_fp, &sc->sc_ownedfp);
211 err |= restore_sigcontext_fpu(sc);
215 regs->tra = -1; /* disable syscall checks */
216 err |= __get_user(*r0_p, &sc->sc_regs[0]);
220 asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5,
221 unsigned long r6, unsigned long r7,
222 struct pt_regs __regs)
224 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
225 struct sigframe __user *frame = (struct sigframe __user *)regs->regs[15];
229 /* Always make any pending restarted system calls return -EINTR */
230 current_thread_info()->restart_block.fn = do_no_restart_syscall;
232 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
235 if (__get_user(set.sig[0], &frame->sc.oldmask)
237 && __copy_from_user(&set.sig[1], &frame->extramask,
238 sizeof(frame->extramask))))
241 sigdelsetmask(&set, ~_BLOCKABLE);
243 spin_lock_irq(¤t->sighand->siglock);
244 current->blocked = set;
246 spin_unlock_irq(¤t->sighand->siglock);
248 if (restore_sigcontext(regs, &frame->sc, &r0))
253 force_sig(SIGSEGV, current);
257 asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5,
258 unsigned long r6, unsigned long r7,
259 struct pt_regs __regs)
261 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
262 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->regs[15];
266 /* Always make any pending restarted system calls return -EINTR */
267 current_thread_info()->restart_block.fn = do_no_restart_syscall;
269 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
272 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
275 sigdelsetmask(&set, ~_BLOCKABLE);
276 spin_lock_irq(¤t->sighand->siglock);
277 current->blocked = set;
279 spin_unlock_irq(¤t->sighand->siglock);
281 if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
284 if (do_sigaltstack(&frame->uc.uc_stack, NULL,
285 regs->regs[15]) == -EFAULT)
291 force_sig(SIGSEGV, current);
296 * Set up a signal frame.
300 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
305 #define COPY(x) err |= __put_user(regs->x, &sc->sc_##x)
306 COPY(regs[0]); COPY(regs[1]);
307 COPY(regs[2]); COPY(regs[3]);
308 COPY(regs[4]); COPY(regs[5]);
309 COPY(regs[6]); COPY(regs[7]);
310 COPY(regs[8]); COPY(regs[9]);
311 COPY(regs[10]); COPY(regs[11]);
312 COPY(regs[12]); COPY(regs[13]);
313 COPY(regs[14]); COPY(regs[15]);
314 COPY(gbr); COPY(mach);
315 COPY(macl); COPY(pr);
320 err |= save_sigcontext_fpu(sc, regs);
323 /* non-iBCS2 extensions.. */
324 err |= __put_user(mask, &sc->oldmask);
330 * Determine which stack to use..
332 static inline void __user *
333 get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
335 if (ka->sa.sa_flags & SA_ONSTACK) {
336 if (sas_ss_flags(sp) == 0)
337 sp = current->sas_ss_sp + current->sas_ss_size;
340 return (void __user *)((sp - (frame_size+UNWINDGUARD)) & -8ul);
343 /* These symbols are defined with the addresses in the vsyscall page.
344 See vsyscall-trapa.S. */
345 extern void __kernel_sigreturn(void);
346 extern void __kernel_rt_sigreturn(void);
348 static int setup_frame(int sig, struct k_sigaction *ka,
349 sigset_t *set, struct pt_regs *regs)
351 struct sigframe __user *frame;
355 frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
357 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
360 signal = current_thread_info()->exec_domain
361 && current_thread_info()->exec_domain->signal_invmap
363 ? current_thread_info()->exec_domain->signal_invmap[sig]
366 err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
369 err |= __copy_to_user(frame->extramask, &set->sig[1],
370 sizeof(frame->extramask));
372 /* Set up to return from userspace. If provided, use a stub
373 already in userspace. */
374 if (ka->sa.sa_flags & SA_RESTORER) {
375 regs->pr = (unsigned long) ka->sa.sa_restorer;
376 #ifdef CONFIG_VSYSCALL
377 } else if (likely(current->mm->context.vdso)) {
378 regs->pr = VDSO_SYM(&__kernel_sigreturn);
381 /* Generate return code (system call to sigreturn) */
382 err |= __put_user(MOVW(7), &frame->retcode[0]);
383 err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
384 err |= __put_user(OR_R0_R0, &frame->retcode[2]);
385 err |= __put_user(OR_R0_R0, &frame->retcode[3]);
386 err |= __put_user(OR_R0_R0, &frame->retcode[4]);
387 err |= __put_user(OR_R0_R0, &frame->retcode[5]);
388 err |= __put_user(OR_R0_R0, &frame->retcode[6]);
389 err |= __put_user((__NR_sigreturn), &frame->retcode[7]);
390 regs->pr = (unsigned long) frame->retcode;
391 flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
397 /* Set up registers for signal handler */
398 regs->regs[15] = (unsigned long) frame;
399 regs->regs[4] = signal; /* Arg for signal handler */
401 regs->regs[6] = (unsigned long) &frame->sc;
403 if (current->personality & FDPIC_FUNCPTRS) {
404 struct fdpic_func_descriptor __user *funcptr =
405 (struct fdpic_func_descriptor __user *)ka->sa.sa_handler;
407 __get_user(regs->pc, &funcptr->text);
408 __get_user(regs->regs[12], &funcptr->GOT);
410 regs->pc = (unsigned long)ka->sa.sa_handler;
414 pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
415 current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
420 force_sigsegv(sig, current);
424 static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
425 sigset_t *set, struct pt_regs *regs)
427 struct rt_sigframe __user *frame;
431 frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
433 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
436 signal = current_thread_info()->exec_domain
437 && current_thread_info()->exec_domain->signal_invmap
439 ? current_thread_info()->exec_domain->signal_invmap[sig]
442 err |= copy_siginfo_to_user(&frame->info, info);
444 /* Create the ucontext. */
445 err |= __put_user(0, &frame->uc.uc_flags);
446 err |= __put_user(NULL, &frame->uc.uc_link);
447 err |= __put_user((void *)current->sas_ss_sp,
448 &frame->uc.uc_stack.ss_sp);
449 err |= __put_user(sas_ss_flags(regs->regs[15]),
450 &frame->uc.uc_stack.ss_flags);
451 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
452 err |= setup_sigcontext(&frame->uc.uc_mcontext,
454 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
456 /* Set up to return from userspace. If provided, use a stub
457 already in userspace. */
458 if (ka->sa.sa_flags & SA_RESTORER) {
459 regs->pr = (unsigned long) ka->sa.sa_restorer;
460 #ifdef CONFIG_VSYSCALL
461 } else if (likely(current->mm->context.vdso)) {
462 regs->pr = VDSO_SYM(&__kernel_rt_sigreturn);
465 /* Generate return code (system call to rt_sigreturn) */
466 err |= __put_user(MOVW(7), &frame->retcode[0]);
467 err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
468 err |= __put_user(OR_R0_R0, &frame->retcode[2]);
469 err |= __put_user(OR_R0_R0, &frame->retcode[3]);
470 err |= __put_user(OR_R0_R0, &frame->retcode[4]);
471 err |= __put_user(OR_R0_R0, &frame->retcode[5]);
472 err |= __put_user(OR_R0_R0, &frame->retcode[6]);
473 err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]);
474 regs->pr = (unsigned long) frame->retcode;
475 flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
481 /* Set up registers for signal handler */
482 regs->regs[15] = (unsigned long) frame;
483 regs->regs[4] = signal; /* Arg for signal handler */
484 regs->regs[5] = (unsigned long) &frame->info;
485 regs->regs[6] = (unsigned long) &frame->uc;
487 if (current->personality & FDPIC_FUNCPTRS) {
488 struct fdpic_func_descriptor __user *funcptr =
489 (struct fdpic_func_descriptor __user *)ka->sa.sa_handler;
491 __get_user(regs->pc, &funcptr->text);
492 __get_user(regs->regs[12], &funcptr->GOT);
494 regs->pc = (unsigned long)ka->sa.sa_handler;
498 pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
499 current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
504 force_sigsegv(sig, current);
509 handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs,
510 struct sigaction *sa)
512 /* If we're not from a syscall, bail out */
516 /* check for system call restart.. */
517 switch (regs->regs[0]) {
518 case -ERESTART_RESTARTBLOCK:
519 case -ERESTARTNOHAND:
520 no_system_call_restart:
521 regs->regs[0] = -EINTR;
525 if (!(sa->sa_flags & SA_RESTART))
526 goto no_system_call_restart;
528 case -ERESTARTNOINTR:
529 regs->regs[0] = save_r0;
530 regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
536 * OK, we're invoking a handler
539 handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
540 sigset_t *oldset, struct pt_regs *regs, unsigned int save_r0)
544 /* Set up the stack frame */
545 if (ka->sa.sa_flags & SA_SIGINFO)
546 ret = setup_rt_frame(sig, ka, info, oldset, regs);
548 ret = setup_frame(sig, ka, oldset, regs);
550 if (ka->sa.sa_flags & SA_ONESHOT)
551 ka->sa.sa_handler = SIG_DFL;
554 spin_lock_irq(¤t->sighand->siglock);
555 sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
556 if (!(ka->sa.sa_flags & SA_NODEFER))
557 sigaddset(¤t->blocked,sig);
559 spin_unlock_irq(¤t->sighand->siglock);
566 * Note that 'init' is a special process: it doesn't get signals it doesn't
567 * want to handle. Thus you cannot kill init even with a SIGKILL even by
570 * Note that we go through the signals twice: once to check the signals that
571 * the kernel can handle, and then we build all the user-level signal handling
572 * stack-frames in one go after that.
574 static void do_signal(struct pt_regs *regs, unsigned int save_r0)
578 struct k_sigaction ka;
582 * We want the common case to go fast, which
583 * is why we may in certain cases get here from
584 * kernel mode. Just return without doing anything
587 if (!user_mode(regs))
590 if (current_thread_info()->status & TS_RESTORE_SIGMASK)
591 oldset = ¤t->saved_sigmask;
593 oldset = ¤t->blocked;
595 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
597 handle_syscall_restart(save_r0, regs, &ka.sa);
599 /* Whee! Actually deliver the signal. */
600 if (handle_signal(signr, &ka, &info, oldset,
601 regs, save_r0) == 0) {
603 * A signal was successfully delivered; the saved
604 * sigmask will have been stored in the signal frame,
605 * and will be restored by sigreturn, so we can simply
606 * clear the TS_RESTORE_SIGMASK flag
608 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
610 tracehook_signal_handler(signr, &info, &ka, regs,
611 test_thread_flag(TIF_SINGLESTEP));
617 /* Did we come from a system call? */
618 if (regs->tra >= 0) {
619 /* Restart the system call - no handlers present */
620 if (regs->regs[0] == -ERESTARTNOHAND ||
621 regs->regs[0] == -ERESTARTSYS ||
622 regs->regs[0] == -ERESTARTNOINTR) {
623 regs->regs[0] = save_r0;
624 regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
625 } else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) {
626 regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
627 regs->regs[3] = __NR_restart_syscall;
632 * If there's no signal to deliver, we just put the saved sigmask
635 if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
636 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
637 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
641 asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
642 unsigned long thread_info_flags)
644 /* deal with pending signal delivery */
645 if (thread_info_flags & _TIF_SIGPENDING)
646 do_signal(regs, save_r0);
648 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
649 clear_thread_flag(TIF_NOTIFY_RESUME);
650 tracehook_notify_resume(regs);
651 if (current->replacement_session_keyring)
652 key_replace_session_keyring();