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686 lines
19 KiB
686 lines
19 KiB
/*
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* linux/arch/alpha/kernel/signal.c
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*
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* Copyright (C) 1995 Linus Torvalds
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*
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* 1997-11-02 Modified for POSIX.1b signals by Richard Henderson
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*/
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <linux/signal.h>
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#include <linux/errno.h>
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#include <linux/wait.h>
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#include <linux/ptrace.h>
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#include <linux/unistd.h>
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#include <linux/mm.h>
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#include <linux/smp.h>
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#include <linux/stddef.h>
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#include <linux/tty.h>
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#include <linux/binfmts.h>
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#include <linux/bitops.h>
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#include <asm/uaccess.h>
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#include <asm/sigcontext.h>
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#include <asm/ucontext.h>
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#include "proto.h"
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#define DEBUG_SIG 0
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#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
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asmlinkage void ret_from_sys_call(void);
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static void do_signal(struct pt_regs *, struct switch_stack *,
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unsigned long, unsigned long);
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/*
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* The OSF/1 sigprocmask calling sequence is different from the
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* C sigprocmask() sequence..
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*
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* how:
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* 1 - SIG_BLOCK
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* 2 - SIG_UNBLOCK
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* 3 - SIG_SETMASK
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*
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* We change the range to -1 .. 1 in order to let gcc easily
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* use the conditional move instructions.
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*
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* Note that we don't need to acquire the kernel lock for SMP
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* operation, as all of this is local to this thread.
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*/
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asmlinkage unsigned long
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do_osf_sigprocmask(int how, unsigned long newmask, struct pt_regs *regs)
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{
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unsigned long oldmask = -EINVAL;
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if ((unsigned long)how-1 <= 2) {
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long sign = how-2; /* -1 .. 1 */
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unsigned long block, unblock;
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newmask &= _BLOCKABLE;
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spin_lock_irq(¤t->sighand->siglock);
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oldmask = current->blocked.sig[0];
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unblock = oldmask & ~newmask;
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block = oldmask | newmask;
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if (!sign)
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block = unblock;
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if (sign <= 0)
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newmask = block;
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if (_NSIG_WORDS > 1 && sign > 0)
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sigemptyset(¤t->blocked);
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current->blocked.sig[0] = newmask;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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regs->r0 = 0; /* special no error return */
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}
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return oldmask;
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}
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asmlinkage int
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osf_sigaction(int sig, const struct osf_sigaction __user *act,
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struct osf_sigaction __user *oact)
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{
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struct k_sigaction new_ka, old_ka;
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int ret;
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if (act) {
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old_sigset_t mask;
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if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
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__get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
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__get_user(new_ka.sa.sa_flags, &act->sa_flags))
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return -EFAULT;
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__get_user(mask, &act->sa_mask);
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siginitset(&new_ka.sa.sa_mask, mask);
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new_ka.ka_restorer = NULL;
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}
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ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
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if (!ret && oact) {
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if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
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__put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
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__put_user(old_ka.sa.sa_flags, &oact->sa_flags))
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return -EFAULT;
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__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
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}
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return ret;
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}
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asmlinkage long
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sys_rt_sigaction(int sig, const struct sigaction __user *act,
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struct sigaction __user *oact,
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size_t sigsetsize, void __user *restorer)
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{
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struct k_sigaction new_ka, old_ka;
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int ret;
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/* XXX: Don't preclude handling different sized sigset_t's. */
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if (sigsetsize != sizeof(sigset_t))
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return -EINVAL;
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if (act) {
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new_ka.ka_restorer = restorer;
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if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
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return -EFAULT;
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}
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ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
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if (!ret && oact) {
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if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
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return -EFAULT;
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}
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return ret;
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}
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/*
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* Atomically swap in the new signal mask, and wait for a signal.
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*/
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asmlinkage int
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do_sigsuspend(old_sigset_t mask, struct pt_regs *regs, struct switch_stack *sw)
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{
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mask &= _BLOCKABLE;
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spin_lock_irq(¤t->sighand->siglock);
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current->saved_sigmask = current->blocked;
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siginitset(¤t->blocked, mask);
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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/* Indicate EINTR on return from any possible signal handler,
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which will not come back through here, but via sigreturn. */
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regs->r0 = EINTR;
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regs->r19 = 1;
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current->state = TASK_INTERRUPTIBLE;
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schedule();
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set_thread_flag(TIF_RESTORE_SIGMASK);
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return -ERESTARTNOHAND;
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}
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asmlinkage int
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do_rt_sigsuspend(sigset_t __user *uset, size_t sigsetsize,
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struct pt_regs *regs, struct switch_stack *sw)
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{
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sigset_t set;
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/* XXX: Don't preclude handling different sized sigset_t's. */
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if (sigsetsize != sizeof(sigset_t))
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return -EINVAL;
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if (copy_from_user(&set, uset, sizeof(set)))
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return -EFAULT;
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sigdelsetmask(&set, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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current->saved_sigmask = current->blocked;
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current->blocked = set;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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/* Indicate EINTR on return from any possible signal handler,
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which will not come back through here, but via sigreturn. */
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regs->r0 = EINTR;
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regs->r19 = 1;
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current->state = TASK_INTERRUPTIBLE;
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schedule();
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set_thread_flag(TIF_RESTORE_SIGMASK);
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return -ERESTARTNOHAND;
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}
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asmlinkage int
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sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
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{
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return do_sigaltstack(uss, uoss, rdusp());
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}
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/*
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* Do a signal return; undo the signal stack.
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*/
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#if _NSIG_WORDS > 1
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# error "Non SA_SIGINFO frame needs rearranging"
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#endif
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struct sigframe
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{
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struct sigcontext sc;
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unsigned int retcode[3];
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};
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struct rt_sigframe
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{
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struct siginfo info;
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struct ucontext uc;
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unsigned int retcode[3];
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};
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/* If this changes, userland unwinders that Know Things about our signal
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frame will break. Do not undertake lightly. It also implies an ABI
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change wrt the size of siginfo_t, which may cause some pain. */
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extern char compile_time_assert
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[offsetof(struct rt_sigframe, uc.uc_mcontext) == 176 ? 1 : -1];
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#define INSN_MOV_R30_R16 0x47fe0410
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#define INSN_LDI_R0 0x201f0000
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#define INSN_CALLSYS 0x00000083
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static long
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restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
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struct switch_stack *sw)
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{
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unsigned long usp;
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long i, err = __get_user(regs->pc, &sc->sc_pc);
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sw->r26 = (unsigned long) ret_from_sys_call;
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err |= __get_user(regs->r0, sc->sc_regs+0);
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err |= __get_user(regs->r1, sc->sc_regs+1);
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err |= __get_user(regs->r2, sc->sc_regs+2);
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err |= __get_user(regs->r3, sc->sc_regs+3);
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err |= __get_user(regs->r4, sc->sc_regs+4);
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err |= __get_user(regs->r5, sc->sc_regs+5);
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err |= __get_user(regs->r6, sc->sc_regs+6);
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err |= __get_user(regs->r7, sc->sc_regs+7);
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err |= __get_user(regs->r8, sc->sc_regs+8);
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err |= __get_user(sw->r9, sc->sc_regs+9);
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err |= __get_user(sw->r10, sc->sc_regs+10);
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err |= __get_user(sw->r11, sc->sc_regs+11);
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err |= __get_user(sw->r12, sc->sc_regs+12);
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err |= __get_user(sw->r13, sc->sc_regs+13);
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err |= __get_user(sw->r14, sc->sc_regs+14);
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err |= __get_user(sw->r15, sc->sc_regs+15);
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err |= __get_user(regs->r16, sc->sc_regs+16);
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err |= __get_user(regs->r17, sc->sc_regs+17);
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err |= __get_user(regs->r18, sc->sc_regs+18);
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err |= __get_user(regs->r19, sc->sc_regs+19);
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err |= __get_user(regs->r20, sc->sc_regs+20);
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err |= __get_user(regs->r21, sc->sc_regs+21);
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err |= __get_user(regs->r22, sc->sc_regs+22);
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err |= __get_user(regs->r23, sc->sc_regs+23);
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err |= __get_user(regs->r24, sc->sc_regs+24);
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err |= __get_user(regs->r25, sc->sc_regs+25);
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err |= __get_user(regs->r26, sc->sc_regs+26);
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err |= __get_user(regs->r27, sc->sc_regs+27);
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err |= __get_user(regs->r28, sc->sc_regs+28);
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err |= __get_user(regs->gp, sc->sc_regs+29);
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err |= __get_user(usp, sc->sc_regs+30);
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wrusp(usp);
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for (i = 0; i < 31; i++)
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err |= __get_user(sw->fp[i], sc->sc_fpregs+i);
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err |= __get_user(sw->fp[31], &sc->sc_fpcr);
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return err;
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}
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/* Note that this syscall is also used by setcontext(3) to install
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a given sigcontext. This because it's impossible to set *all*
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registers and transfer control from userland. */
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asmlinkage void
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do_sigreturn(struct sigcontext __user *sc, struct pt_regs *regs,
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struct switch_stack *sw)
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{
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sigset_t set;
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/* Verify that it's a good sigcontext before using it */
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if (!access_ok(VERIFY_READ, sc, sizeof(*sc)))
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goto give_sigsegv;
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if (__get_user(set.sig[0], &sc->sc_mask))
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goto give_sigsegv;
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sigdelsetmask(&set, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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current->blocked = set;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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if (restore_sigcontext(sc, regs, sw))
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goto give_sigsegv;
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/* Send SIGTRAP if we're single-stepping: */
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if (ptrace_cancel_bpt (current)) {
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siginfo_t info;
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info.si_signo = SIGTRAP;
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info.si_errno = 0;
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info.si_code = TRAP_BRKPT;
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info.si_addr = (void __user *) regs->pc;
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info.si_trapno = 0;
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send_sig_info(SIGTRAP, &info, current);
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}
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return;
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give_sigsegv:
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force_sig(SIGSEGV, current);
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}
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asmlinkage void
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do_rt_sigreturn(struct rt_sigframe __user *frame, struct pt_regs *regs,
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struct switch_stack *sw)
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{
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sigset_t set;
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/* Verify that it's a good ucontext_t before using it */
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if (!access_ok(VERIFY_READ, &frame->uc, sizeof(frame->uc)))
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goto give_sigsegv;
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if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
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goto give_sigsegv;
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sigdelsetmask(&set, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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current->blocked = set;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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if (restore_sigcontext(&frame->uc.uc_mcontext, regs, sw))
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goto give_sigsegv;
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/* Send SIGTRAP if we're single-stepping: */
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if (ptrace_cancel_bpt (current)) {
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siginfo_t info;
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info.si_signo = SIGTRAP;
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info.si_errno = 0;
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info.si_code = TRAP_BRKPT;
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info.si_addr = (void __user *) regs->pc;
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info.si_trapno = 0;
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send_sig_info(SIGTRAP, &info, current);
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}
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return;
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give_sigsegv:
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force_sig(SIGSEGV, current);
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}
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/*
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* Set up a signal frame.
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*/
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static inline void __user *
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get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
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{
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if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
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sp = current->sas_ss_sp + current->sas_ss_size;
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return (void __user *)((sp - frame_size) & -32ul);
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}
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static long
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setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
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struct switch_stack *sw, unsigned long mask, unsigned long sp)
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{
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long i, err = 0;
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err |= __put_user(on_sig_stack((unsigned long)sc), &sc->sc_onstack);
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err |= __put_user(mask, &sc->sc_mask);
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err |= __put_user(regs->pc, &sc->sc_pc);
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err |= __put_user(8, &sc->sc_ps);
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err |= __put_user(regs->r0 , sc->sc_regs+0);
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err |= __put_user(regs->r1 , sc->sc_regs+1);
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err |= __put_user(regs->r2 , sc->sc_regs+2);
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err |= __put_user(regs->r3 , sc->sc_regs+3);
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err |= __put_user(regs->r4 , sc->sc_regs+4);
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err |= __put_user(regs->r5 , sc->sc_regs+5);
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err |= __put_user(regs->r6 , sc->sc_regs+6);
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err |= __put_user(regs->r7 , sc->sc_regs+7);
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err |= __put_user(regs->r8 , sc->sc_regs+8);
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err |= __put_user(sw->r9 , sc->sc_regs+9);
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err |= __put_user(sw->r10 , sc->sc_regs+10);
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err |= __put_user(sw->r11 , sc->sc_regs+11);
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err |= __put_user(sw->r12 , sc->sc_regs+12);
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err |= __put_user(sw->r13 , sc->sc_regs+13);
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err |= __put_user(sw->r14 , sc->sc_regs+14);
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err |= __put_user(sw->r15 , sc->sc_regs+15);
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err |= __put_user(regs->r16, sc->sc_regs+16);
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err |= __put_user(regs->r17, sc->sc_regs+17);
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err |= __put_user(regs->r18, sc->sc_regs+18);
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err |= __put_user(regs->r19, sc->sc_regs+19);
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err |= __put_user(regs->r20, sc->sc_regs+20);
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err |= __put_user(regs->r21, sc->sc_regs+21);
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err |= __put_user(regs->r22, sc->sc_regs+22);
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err |= __put_user(regs->r23, sc->sc_regs+23);
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err |= __put_user(regs->r24, sc->sc_regs+24);
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err |= __put_user(regs->r25, sc->sc_regs+25);
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err |= __put_user(regs->r26, sc->sc_regs+26);
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err |= __put_user(regs->r27, sc->sc_regs+27);
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err |= __put_user(regs->r28, sc->sc_regs+28);
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err |= __put_user(regs->gp , sc->sc_regs+29);
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err |= __put_user(sp, sc->sc_regs+30);
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err |= __put_user(0, sc->sc_regs+31);
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for (i = 0; i < 31; i++)
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err |= __put_user(sw->fp[i], sc->sc_fpregs+i);
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err |= __put_user(0, sc->sc_fpregs+31);
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err |= __put_user(sw->fp[31], &sc->sc_fpcr);
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err |= __put_user(regs->trap_a0, &sc->sc_traparg_a0);
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err |= __put_user(regs->trap_a1, &sc->sc_traparg_a1);
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err |= __put_user(regs->trap_a2, &sc->sc_traparg_a2);
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return err;
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}
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static int
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setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
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struct pt_regs *regs, struct switch_stack * sw)
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{
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unsigned long oldsp, r26, err = 0;
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struct sigframe __user *frame;
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oldsp = rdusp();
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frame = get_sigframe(ka, oldsp, sizeof(*frame));
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if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
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goto give_sigsegv;
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err |= setup_sigcontext(&frame->sc, regs, sw, set->sig[0], oldsp);
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if (err)
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goto give_sigsegv;
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/* Set up to return from userspace. If provided, use a stub
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already in userspace. */
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if (ka->ka_restorer) {
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r26 = (unsigned long) ka->ka_restorer;
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} else {
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err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
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err |= __put_user(INSN_LDI_R0+__NR_sigreturn, frame->retcode+1);
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err |= __put_user(INSN_CALLSYS, frame->retcode+2);
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imb();
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r26 = (unsigned long) frame->retcode;
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}
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/* Check that everything was written properly. */
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if (err)
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goto give_sigsegv;
|
|
|
|
/* "Return" to the handler */
|
|
regs->r26 = r26;
|
|
regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
|
|
regs->r16 = sig; /* a0: signal number */
|
|
regs->r17 = 0; /* a1: exception code */
|
|
regs->r18 = (unsigned long) &frame->sc; /* a2: sigcontext pointer */
|
|
wrusp((unsigned long) frame);
|
|
|
|
#if DEBUG_SIG
|
|
printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
|
|
current->comm, current->pid, frame, regs->pc, regs->r26);
|
|
#endif
|
|
|
|
return 0;
|
|
|
|
give_sigsegv:
|
|
force_sigsegv(sig, current);
|
|
return -EFAULT;
|
|
}
|
|
|
|
static int
|
|
setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
|
|
sigset_t *set, struct pt_regs *regs, struct switch_stack * sw)
|
|
{
|
|
unsigned long oldsp, r26, err = 0;
|
|
struct rt_sigframe __user *frame;
|
|
|
|
oldsp = rdusp();
|
|
frame = get_sigframe(ka, oldsp, sizeof(*frame));
|
|
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
|
|
goto give_sigsegv;
|
|
|
|
err |= copy_siginfo_to_user(&frame->info, info);
|
|
|
|
/* Create the ucontext. */
|
|
err |= __put_user(0, &frame->uc.uc_flags);
|
|
err |= __put_user(0, &frame->uc.uc_link);
|
|
err |= __put_user(set->sig[0], &frame->uc.uc_osf_sigmask);
|
|
err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
|
|
err |= __put_user(sas_ss_flags(oldsp), &frame->uc.uc_stack.ss_flags);
|
|
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
|
|
err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, sw,
|
|
set->sig[0], oldsp);
|
|
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
|
|
if (err)
|
|
goto give_sigsegv;
|
|
|
|
/* Set up to return from userspace. If provided, use a stub
|
|
already in userspace. */
|
|
if (ka->ka_restorer) {
|
|
r26 = (unsigned long) ka->ka_restorer;
|
|
} else {
|
|
err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
|
|
err |= __put_user(INSN_LDI_R0+__NR_rt_sigreturn,
|
|
frame->retcode+1);
|
|
err |= __put_user(INSN_CALLSYS, frame->retcode+2);
|
|
imb();
|
|
r26 = (unsigned long) frame->retcode;
|
|
}
|
|
|
|
if (err)
|
|
goto give_sigsegv;
|
|
|
|
/* "Return" to the handler */
|
|
regs->r26 = r26;
|
|
regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
|
|
regs->r16 = sig; /* a0: signal number */
|
|
regs->r17 = (unsigned long) &frame->info; /* a1: siginfo pointer */
|
|
regs->r18 = (unsigned long) &frame->uc; /* a2: ucontext pointer */
|
|
wrusp((unsigned long) frame);
|
|
|
|
#if DEBUG_SIG
|
|
printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
|
|
current->comm, current->pid, frame, regs->pc, regs->r26);
|
|
#endif
|
|
|
|
return 0;
|
|
|
|
give_sigsegv:
|
|
force_sigsegv(sig, current);
|
|
return -EFAULT;
|
|
}
|
|
|
|
|
|
/*
|
|
* OK, we're invoking a handler.
|
|
*/
|
|
static inline int
|
|
handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
|
|
sigset_t *oldset, struct pt_regs * regs, struct switch_stack *sw)
|
|
{
|
|
int ret;
|
|
|
|
if (ka->sa.sa_flags & SA_SIGINFO)
|
|
ret = setup_rt_frame(sig, ka, info, oldset, regs, sw);
|
|
else
|
|
ret = setup_frame(sig, ka, oldset, regs, sw);
|
|
|
|
if (ret == 0) {
|
|
spin_lock_irq(¤t->sighand->siglock);
|
|
sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
|
|
if (!(ka->sa.sa_flags & SA_NODEFER))
|
|
sigaddset(¤t->blocked,sig);
|
|
recalc_sigpending();
|
|
spin_unlock_irq(¤t->sighand->siglock);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static inline void
|
|
syscall_restart(unsigned long r0, unsigned long r19,
|
|
struct pt_regs *regs, struct k_sigaction *ka)
|
|
{
|
|
switch (regs->r0) {
|
|
case ERESTARTSYS:
|
|
if (!(ka->sa.sa_flags & SA_RESTART)) {
|
|
case ERESTARTNOHAND:
|
|
regs->r0 = EINTR;
|
|
break;
|
|
}
|
|
/* fallthrough */
|
|
case ERESTARTNOINTR:
|
|
regs->r0 = r0; /* reset v0 and a3 and replay syscall */
|
|
regs->r19 = r19;
|
|
regs->pc -= 4;
|
|
break;
|
|
case ERESTART_RESTARTBLOCK:
|
|
current_thread_info()->restart_block.fn = do_no_restart_syscall;
|
|
regs->r0 = EINTR;
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Note that 'init' is a special process: it doesn't get signals it doesn't
|
|
* want to handle. Thus you cannot kill init even with a SIGKILL even by
|
|
* mistake.
|
|
*
|
|
* Note that we go through the signals twice: once to check the signals that
|
|
* the kernel can handle, and then we build all the user-level signal handling
|
|
* stack-frames in one go after that.
|
|
*
|
|
* "r0" and "r19" are the registers we need to restore for system call
|
|
* restart. "r0" is also used as an indicator whether we can restart at
|
|
* all (if we get here from anything but a syscall return, it will be 0)
|
|
*/
|
|
static void
|
|
do_signal(struct pt_regs * regs, struct switch_stack * sw,
|
|
unsigned long r0, unsigned long r19)
|
|
{
|
|
siginfo_t info;
|
|
int signr;
|
|
unsigned long single_stepping = ptrace_cancel_bpt(current);
|
|
struct k_sigaction ka;
|
|
sigset_t *oldset;
|
|
|
|
if (test_thread_flag(TIF_RESTORE_SIGMASK))
|
|
oldset = ¤t->saved_sigmask;
|
|
else
|
|
oldset = ¤t->blocked;
|
|
|
|
/* This lets the debugger run, ... */
|
|
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
|
|
|
|
/* ... so re-check the single stepping. */
|
|
single_stepping |= ptrace_cancel_bpt(current);
|
|
|
|
if (signr > 0) {
|
|
/* Whee! Actually deliver the signal. */
|
|
if (r0)
|
|
syscall_restart(r0, r19, regs, &ka);
|
|
if (handle_signal(signr, &ka, &info, oldset, regs, sw) == 0) {
|
|
/* A signal was successfully delivered, and the
|
|
saved sigmask was stored on the signal frame,
|
|
and will be restored by sigreturn. So we can
|
|
simply clear the restore sigmask flag. */
|
|
if (test_thread_flag(TIF_RESTORE_SIGMASK))
|
|
clear_thread_flag(TIF_RESTORE_SIGMASK);
|
|
}
|
|
if (single_stepping)
|
|
ptrace_set_bpt(current); /* re-set bpt */
|
|
return;
|
|
}
|
|
|
|
if (r0) {
|
|
switch (regs->r0) {
|
|
case ERESTARTNOHAND:
|
|
case ERESTARTSYS:
|
|
case ERESTARTNOINTR:
|
|
/* Reset v0 and a3 and replay syscall. */
|
|
regs->r0 = r0;
|
|
regs->r19 = r19;
|
|
regs->pc -= 4;
|
|
break;
|
|
case ERESTART_RESTARTBLOCK:
|
|
/* Force v0 to the restart syscall and reply. */
|
|
regs->r0 = __NR_restart_syscall;
|
|
regs->pc -= 4;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* If there's no signal to deliver, we just restore the saved mask. */
|
|
if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
|
|
clear_thread_flag(TIF_RESTORE_SIGMASK);
|
|
sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
|
|
}
|
|
|
|
if (single_stepping)
|
|
ptrace_set_bpt(current); /* re-set breakpoint */
|
|
}
|
|
|
|
void
|
|
do_notify_resume(struct pt_regs *regs, struct switch_stack *sw,
|
|
unsigned long thread_info_flags,
|
|
unsigned long r0, unsigned long r19)
|
|
{
|
|
if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
|
|
do_signal(regs, sw, r0, r19);
|
|
}
|
|
|