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-rw-r--r--arch/i386/kernel/signal.c667
1 files changed, 0 insertions, 667 deletions
diff --git a/arch/i386/kernel/signal.c b/arch/i386/kernel/signal.c
deleted file mode 100644
index f5dd85656c1..00000000000
--- a/arch/i386/kernel/signal.c
+++ /dev/null
@@ -1,667 +0,0 @@
-/*
- * linux/arch/i386/kernel/signal.c
- *
- * Copyright (C) 1991, 1992 Linus Torvalds
- *
- * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
- * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes
- */
-
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
-#include <linux/kernel.h>
-#include <linux/signal.h>
-#include <linux/errno.h>
-#include <linux/wait.h>
-#include <linux/unistd.h>
-#include <linux/stddef.h>
-#include <linux/personality.h>
-#include <linux/suspend.h>
-#include <linux/ptrace.h>
-#include <linux/elf.h>
-#include <linux/binfmts.h>
-#include <asm/processor.h>
-#include <asm/ucontext.h>
-#include <asm/uaccess.h>
-#include <asm/i387.h>
-#include "sigframe.h"
-
-#define DEBUG_SIG 0
-
-#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
-
-/*
- * Atomically swap in the new signal mask, and wait for a signal.
- */
-asmlinkage int
-sys_sigsuspend(int history0, int history1, old_sigset_t mask)
-{
- mask &= _BLOCKABLE;
- spin_lock_irq(&current->sighand->siglock);
- current->saved_sigmask = current->blocked;
- siginitset(&current->blocked, mask);
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
-
- current->state = TASK_INTERRUPTIBLE;
- schedule();
- set_thread_flag(TIF_RESTORE_SIGMASK);
- return -ERESTARTNOHAND;
-}
-
-asmlinkage int
-sys_sigaction(int sig, const struct old_sigaction __user *act,
- struct old_sigaction __user *oact)
-{
- struct k_sigaction new_ka, old_ka;
- int ret;
-
- if (act) {
- old_sigset_t mask;
- if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
- __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
- __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
- return -EFAULT;
- __get_user(new_ka.sa.sa_flags, &act->sa_flags);
- __get_user(mask, &act->sa_mask);
- siginitset(&new_ka.sa.sa_mask, mask);
- }
-
- ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
-
- if (!ret && oact) {
- if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
- __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
- __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
- return -EFAULT;
- __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
- __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
- }
-
- return ret;
-}
-
-asmlinkage int
-sys_sigaltstack(unsigned long ebx)
-{
- /* This is needed to make gcc realize it doesn't own the "struct pt_regs" */
- struct pt_regs *regs = (struct pt_regs *)&ebx;
- const stack_t __user *uss = (const stack_t __user *)ebx;
- stack_t __user *uoss = (stack_t __user *)regs->ecx;
-
- return do_sigaltstack(uss, uoss, regs->esp);
-}
-
-
-/*
- * Do a signal return; undo the signal stack.
- */
-
-static int
-restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *peax)
-{
- unsigned int err = 0;
-
- /* Always make any pending restarted system calls return -EINTR */
- current_thread_info()->restart_block.fn = do_no_restart_syscall;
-
-#define COPY(x) err |= __get_user(regs->x, &sc->x)
-
-#define COPY_SEG(seg) \
- { unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
- regs->x##seg = tmp; }
-
-#define COPY_SEG_STRICT(seg) \
- { unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
- regs->x##seg = tmp|3; }
-
-#define GET_SEG(seg) \
- { unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
- loadsegment(seg,tmp); }
-
-#define FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_RF | \
- X86_EFLAGS_OF | X86_EFLAGS_DF | \
- X86_EFLAGS_TF | X86_EFLAGS_SF | X86_EFLAGS_ZF | \
- X86_EFLAGS_AF | X86_EFLAGS_PF | X86_EFLAGS_CF)
-
- GET_SEG(gs);
- COPY_SEG(fs);
- COPY_SEG(es);
- COPY_SEG(ds);
- COPY(edi);
- COPY(esi);
- COPY(ebp);
- COPY(esp);
- COPY(ebx);
- COPY(edx);
- COPY(ecx);
- COPY(eip);
- COPY_SEG_STRICT(cs);
- COPY_SEG_STRICT(ss);
-
- {
- unsigned int tmpflags;
- err |= __get_user(tmpflags, &sc->eflags);
- regs->eflags = (regs->eflags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
- regs->orig_eax = -1; /* disable syscall checks */
- }
-
- {
- struct _fpstate __user * buf;
- err |= __get_user(buf, &sc->fpstate);
- if (buf) {
- if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
- goto badframe;
- err |= restore_i387(buf);
- } else {
- struct task_struct *me = current;
- if (used_math()) {
- clear_fpu(me);
- clear_used_math();
- }
- }
- }
-
- err |= __get_user(*peax, &sc->eax);
- return err;
-
-badframe:
- return 1;
-}
-
-asmlinkage int sys_sigreturn(unsigned long __unused)
-{
- struct pt_regs *regs = (struct pt_regs *) &__unused;
- struct sigframe __user *frame = (struct sigframe __user *)(regs->esp - 8);
- sigset_t set;
- int eax;
-
- if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
- goto badframe;
- if (__get_user(set.sig[0], &frame->sc.oldmask)
- || (_NSIG_WORDS > 1
- && __copy_from_user(&set.sig[1], &frame->extramask,
- sizeof(frame->extramask))))
- goto badframe;
-
- sigdelsetmask(&set, ~_BLOCKABLE);
- spin_lock_irq(&current->sighand->siglock);
- current->blocked = set;
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
-
- if (restore_sigcontext(regs, &frame->sc, &eax))
- goto badframe;
- return eax;
-
-badframe:
- if (show_unhandled_signals && printk_ratelimit())
- printk("%s%s[%d] bad frame in sigreturn frame:%p eip:%lx"
- " esp:%lx oeax:%lx\n",
- current->pid > 1 ? KERN_INFO : KERN_EMERG,
- current->comm, current->pid, frame, regs->eip,
- regs->esp, regs->orig_eax);
-
- force_sig(SIGSEGV, current);
- return 0;
-}
-
-asmlinkage int sys_rt_sigreturn(unsigned long __unused)
-{
- struct pt_regs *regs = (struct pt_regs *) &__unused;
- struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(regs->esp - 4);
- sigset_t set;
- int eax;
-
- if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
- goto badframe;
- if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
- goto badframe;
-
- sigdelsetmask(&set, ~_BLOCKABLE);
- spin_lock_irq(&current->sighand->siglock);
- current->blocked = set;
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
-
- if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax))
- goto badframe;
-
- if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->esp) == -EFAULT)
- goto badframe;
-
- return eax;
-
-badframe:
- force_sig(SIGSEGV, current);
- return 0;
-}
-
-/*
- * Set up a signal frame.
- */
-
-static int
-setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
- struct pt_regs *regs, unsigned long mask)
-{
- int tmp, err = 0;
-
- err |= __put_user(regs->xfs, (unsigned int __user *)&sc->fs);
- savesegment(gs, tmp);
- err |= __put_user(tmp, (unsigned int __user *)&sc->gs);
-
- err |= __put_user(regs->xes, (unsigned int __user *)&sc->es);
- err |= __put_user(regs->xds, (unsigned int __user *)&sc->ds);
- err |= __put_user(regs->edi, &sc->edi);
- err |= __put_user(regs->esi, &sc->esi);
- err |= __put_user(regs->ebp, &sc->ebp);
- err |= __put_user(regs->esp, &sc->esp);
- err |= __put_user(regs->ebx, &sc->ebx);
- err |= __put_user(regs->edx, &sc->edx);
- err |= __put_user(regs->ecx, &sc->ecx);
- err |= __put_user(regs->eax, &sc->eax);
- err |= __put_user(current->thread.trap_no, &sc->trapno);
- err |= __put_user(current->thread.error_code, &sc->err);
- err |= __put_user(regs->eip, &sc->eip);
- err |= __put_user(regs->xcs, (unsigned int __user *)&sc->cs);
- err |= __put_user(regs->eflags, &sc->eflags);
- err |= __put_user(regs->esp, &sc->esp_at_signal);
- err |= __put_user(regs->xss, (unsigned int __user *)&sc->ss);
-
- tmp = save_i387(fpstate);
- if (tmp < 0)
- err = 1;
- else
- err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate);
-
- /* non-iBCS2 extensions.. */
- err |= __put_user(mask, &sc->oldmask);
- err |= __put_user(current->thread.cr2, &sc->cr2);
-
- return err;
-}
-
-/*
- * Determine which stack to use..
- */
-static inline void __user *
-get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
-{
- unsigned long esp;
-
- /* Default to using normal stack */
- esp = regs->esp;
-
- /* This is the X/Open sanctioned signal stack switching. */
- if (ka->sa.sa_flags & SA_ONSTACK) {
- if (sas_ss_flags(esp) == 0)
- esp = current->sas_ss_sp + current->sas_ss_size;
- }
-
- /* This is the legacy signal stack switching. */
- else if ((regs->xss & 0xffff) != __USER_DS &&
- !(ka->sa.sa_flags & SA_RESTORER) &&
- ka->sa.sa_restorer) {
- esp = (unsigned long) ka->sa.sa_restorer;
- }
-
- esp -= frame_size;
- /* Align the stack pointer according to the i386 ABI,
- * i.e. so that on function entry ((sp + 4) & 15) == 0. */
- esp = ((esp + 4) & -16ul) - 4;
- return (void __user *) esp;
-}
-
-/* These symbols are defined with the addresses in the vsyscall page.
- See vsyscall-sigreturn.S. */
-extern void __user __kernel_sigreturn;
-extern void __user __kernel_rt_sigreturn;
-
-static int setup_frame(int sig, struct k_sigaction *ka,
- sigset_t *set, struct pt_regs * regs)
-{
- void __user *restorer;
- struct sigframe __user *frame;
- int err = 0;
- int usig;
-
- frame = get_sigframe(ka, regs, sizeof(*frame));
-
- if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
- goto give_sigsegv;
-
- usig = current_thread_info()->exec_domain
- && current_thread_info()->exec_domain->signal_invmap
- && sig < 32
- ? current_thread_info()->exec_domain->signal_invmap[sig]
- : sig;
-
- err = __put_user(usig, &frame->sig);
- if (err)
- goto give_sigsegv;
-
- err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]);
- if (err)
- goto give_sigsegv;
-
- if (_NSIG_WORDS > 1) {
- err = __copy_to_user(&frame->extramask, &set->sig[1],
- sizeof(frame->extramask));
- if (err)
- goto give_sigsegv;
- }
-
- if (current->binfmt->hasvdso)
- restorer = (void *)VDSO_SYM(&__kernel_sigreturn);
- else
- restorer = (void *)&frame->retcode;
- if (ka->sa.sa_flags & SA_RESTORER)
- restorer = ka->sa.sa_restorer;
-
- /* Set up to return from userspace. */
- err |= __put_user(restorer, &frame->pretcode);
-
- /*
- * This is popl %eax ; movl $,%eax ; int $0x80
- *
- * WE DO NOT USE IT ANY MORE! It's only left here for historical
- * reasons and because gdb uses it as a signature to notice
- * signal handler stack frames.
- */
- err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
- err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
- err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
-
- if (err)
- goto give_sigsegv;
-
- /* Set up registers for signal handler */
- regs->esp = (unsigned long) frame;
- regs->eip = (unsigned long) ka->sa.sa_handler;
- regs->eax = (unsigned long) sig;
- regs->edx = (unsigned long) 0;
- regs->ecx = (unsigned long) 0;
-
- set_fs(USER_DS);
- regs->xds = __USER_DS;
- regs->xes = __USER_DS;
- regs->xss = __USER_DS;
- regs->xcs = __USER_CS;
-
- /*
- * Clear TF when entering the signal handler, but
- * notify any tracer that was single-stepping it.
- * The tracer may want to single-step inside the
- * handler too.
- */
- regs->eflags &= ~TF_MASK;
- if (test_thread_flag(TIF_SINGLESTEP))
- ptrace_notify(SIGTRAP);
-
-#if DEBUG_SIG
- printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
- current->comm, current->pid, frame, regs->eip, frame->pretcode);
-#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)
-{
- void __user *restorer;
- struct rt_sigframe __user *frame;
- int err = 0;
- int usig;
-
- frame = get_sigframe(ka, regs, sizeof(*frame));
-
- if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
- goto give_sigsegv;
-
- usig = current_thread_info()->exec_domain
- && current_thread_info()->exec_domain->signal_invmap
- && sig < 32
- ? current_thread_info()->exec_domain->signal_invmap[sig]
- : sig;
-
- err |= __put_user(usig, &frame->sig);
- err |= __put_user(&frame->info, &frame->pinfo);
- err |= __put_user(&frame->uc, &frame->puc);
- err |= copy_siginfo_to_user(&frame->info, info);
- if (err)
- goto give_sigsegv;
-
- /* Create the ucontext. */
- err |= __put_user(0, &frame->uc.uc_flags);
- err |= __put_user(0, &frame->uc.uc_link);
- err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
- err |= __put_user(sas_ss_flags(regs->esp),
- &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, &frame->fpstate,
- regs, set->sig[0]);
- err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
- if (err)
- goto give_sigsegv;
-
- /* Set up to return from userspace. */
- restorer = (void *)VDSO_SYM(&__kernel_rt_sigreturn);
- if (ka->sa.sa_flags & SA_RESTORER)
- restorer = ka->sa.sa_restorer;
- err |= __put_user(restorer, &frame->pretcode);
-
- /*
- * This is movl $,%eax ; int $0x80
- *
- * WE DO NOT USE IT ANY MORE! It's only left here for historical
- * reasons and because gdb uses it as a signature to notice
- * signal handler stack frames.
- */
- err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
- err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
- err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
-
- if (err)
- goto give_sigsegv;
-
- /* Set up registers for signal handler */
- regs->esp = (unsigned long) frame;
- regs->eip = (unsigned long) ka->sa.sa_handler;
- regs->eax = (unsigned long) usig;
- regs->edx = (unsigned long) &frame->info;
- regs->ecx = (unsigned long) &frame->uc;
-
- set_fs(USER_DS);
- regs->xds = __USER_DS;
- regs->xes = __USER_DS;
- regs->xss = __USER_DS;
- regs->xcs = __USER_CS;
-
- /*
- * Clear TF when entering the signal handler, but
- * notify any tracer that was single-stepping it.
- * The tracer may want to single-step inside the
- * handler too.
- */
- regs->eflags &= ~TF_MASK;
- if (test_thread_flag(TIF_SINGLESTEP))
- ptrace_notify(SIGTRAP);
-
-#if DEBUG_SIG
- printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
- current->comm, current->pid, frame, regs->eip, frame->pretcode);
-#endif
-
- return 0;
-
-give_sigsegv:
- force_sigsegv(sig, current);
- return -EFAULT;
-}
-
-/*
- * OK, we're invoking a handler
- */
-
-static int
-handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
- sigset_t *oldset, struct pt_regs * regs)
-{
- int ret;
-
- /* Are we from a system call? */
- if (regs->orig_eax >= 0) {
- /* If so, check system call restarting.. */
- switch (regs->eax) {
- case -ERESTART_RESTARTBLOCK:
- case -ERESTARTNOHAND:
- regs->eax = -EINTR;
- break;
-
- case -ERESTARTSYS:
- if (!(ka->sa.sa_flags & SA_RESTART)) {
- regs->eax = -EINTR;
- break;
- }
- /* fallthrough */
- case -ERESTARTNOINTR:
- regs->eax = regs->orig_eax;
- regs->eip -= 2;
- }
- }
-
- /*
- * If TF is set due to a debugger (PT_DTRACE), clear the TF flag so
- * that register information in the sigcontext is correct.
- */
- if (unlikely(regs->eflags & TF_MASK)
- && likely(current->ptrace & PT_DTRACE)) {
- current->ptrace &= ~PT_DTRACE;
- regs->eflags &= ~TF_MASK;
- }
-
- /* Set up the stack frame */
- if (ka->sa.sa_flags & SA_SIGINFO)
- ret = setup_rt_frame(sig, ka, info, oldset, regs);
- else
- ret = setup_frame(sig, ka, oldset, regs);
-
- if (ret == 0) {
- spin_lock_irq(&current->sighand->siglock);
- sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
- if (!(ka->sa.sa_flags & SA_NODEFER))
- sigaddset(&current->blocked,sig);
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
- }
-
- return ret;
-}
-
-/*
- * 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.
- */
-static void fastcall do_signal(struct pt_regs *regs)
-{
- siginfo_t info;
- int signr;
- struct k_sigaction ka;
- sigset_t *oldset;
-
- /*
- * We want the common case to go fast, which
- * is why we may in certain cases get here from
- * kernel mode. Just return without doing anything
- * if so. vm86 regs switched out by assembly code
- * before reaching here, so testing against kernel
- * CS suffices.
- */
- if (!user_mode(regs))
- return;
-
- if (test_thread_flag(TIF_RESTORE_SIGMASK))
- oldset = &current->saved_sigmask;
- else
- oldset = &current->blocked;
-
- signr = get_signal_to_deliver(&info, &ka, regs, NULL);
- if (signr > 0) {
- /* Reenable any watchpoints before delivering the
- * signal to user space. The processor register will
- * have been cleared if the watchpoint triggered
- * inside the kernel.
- */
- if (unlikely(current->thread.debugreg[7]))
- set_debugreg(current->thread.debugreg[7], 7);
-
- /* Whee! Actually deliver the signal. */
- if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
- /* a signal was successfully delivered; the saved
- * sigmask will have been stored in the signal frame,
- * and will be restored by sigreturn, so we can simply
- * clear the TIF_RESTORE_SIGMASK flag */
- if (test_thread_flag(TIF_RESTORE_SIGMASK))
- clear_thread_flag(TIF_RESTORE_SIGMASK);
- }
-
- return;
- }
-
- /* Did we come from a system call? */
- if (regs->orig_eax >= 0) {
- /* Restart the system call - no handlers present */
- switch (regs->eax) {
- case -ERESTARTNOHAND:
- case -ERESTARTSYS:
- case -ERESTARTNOINTR:
- regs->eax = regs->orig_eax;
- regs->eip -= 2;
- break;
-
- case -ERESTART_RESTARTBLOCK:
- regs->eax = __NR_restart_syscall;
- regs->eip -= 2;
- break;
- }
- }
-
- /* if there's no signal to deliver, we just put the saved sigmask
- * back */
- if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
- clear_thread_flag(TIF_RESTORE_SIGMASK);
- sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
- }
-}
-
-/*
- * notification of userspace execution resumption
- * - triggered by the TIF_WORK_MASK flags
- */
-__attribute__((regparm(3)))
-void do_notify_resume(struct pt_regs *regs, void *_unused,
- __u32 thread_info_flags)
-{
- /* Pending single-step? */
- if (thread_info_flags & _TIF_SINGLESTEP) {
- regs->eflags |= TF_MASK;
- clear_thread_flag(TIF_SINGLESTEP);
- }
-
- /* deal with pending signal delivery */
- if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
- do_signal(regs);
-
- clear_thread_flag(TIF_IRET);
-}