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authorRusty Russell <rusty@rustcorp.com.au>2008-12-30 08:02:35 +1030
committerRusty Russell <rusty@rustcorp.com.au>2008-12-30 08:02:35 +1030
commit33edcf133ba93ecba2e4b6472e97b689895d805c (patch)
tree327d7a20acef64005e7c5ccbfa1265be28aeb6ac /arch/x86/kernel/signal_64.c
parentbe4d638c1597580ed2294d899d9f1a2cd10e462c (diff)
parent3c92ec8ae91ecf59d88c798301833d7cf83f2179 (diff)
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Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Diffstat (limited to 'arch/x86/kernel/signal_64.c')
-rw-r--r--arch/x86/kernel/signal_64.c516
1 files changed, 0 insertions, 516 deletions
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
deleted file mode 100644
index a5c9627f4db9..000000000000
--- a/arch/x86/kernel/signal_64.c
+++ /dev/null
@@ -1,516 +0,0 @@
-/*
- * Copyright (C) 1991, 1992 Linus Torvalds
- * Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs
- *
- * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
- * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes
- * 2000-2002 x86-64 support by Andi Kleen
- */
-
-#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/ptrace.h>
-#include <linux/tracehook.h>
-#include <linux/unistd.h>
-#include <linux/stddef.h>
-#include <linux/personality.h>
-#include <linux/compiler.h>
-#include <linux/uaccess.h>
-
-#include <asm/processor.h>
-#include <asm/ucontext.h>
-#include <asm/i387.h>
-#include <asm/proto.h>
-#include <asm/ia32_unistd.h>
-#include <asm/mce.h>
-#include <asm/syscall.h>
-#include <asm/syscalls.h>
-#include "sigframe.h"
-
-#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
-
-#define __FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | \
- X86_EFLAGS_DF | X86_EFLAGS_TF | X86_EFLAGS_SF | \
- X86_EFLAGS_ZF | X86_EFLAGS_AF | X86_EFLAGS_PF | \
- X86_EFLAGS_CF)
-
-#ifdef CONFIG_X86_32
-# define FIX_EFLAGS (__FIX_EFLAGS | X86_EFLAGS_RF)
-#else
-# define FIX_EFLAGS __FIX_EFLAGS
-#endif
-
-asmlinkage long
-sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
- struct pt_regs *regs)
-{
- return do_sigaltstack(uss, uoss, regs->sp);
-}
-
-#define COPY(x) { \
- err |= __get_user(regs->x, &sc->x); \
-}
-
-#define COPY_SEG_STRICT(seg) { \
- unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
- regs->seg = tmp | 3; \
-}
-
-/*
- * Do a signal return; undo the signal stack.
- */
-static int
-restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
- unsigned long *pax)
-{
- void __user *buf;
- unsigned int tmpflags;
- unsigned int err = 0;
-
- /* Always make any pending restarted system calls return -EINTR */
- current_thread_info()->restart_block.fn = do_no_restart_syscall;
-
- COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
- COPY(dx); COPY(cx); COPY(ip);
- COPY(r8);
- COPY(r9);
- COPY(r10);
- COPY(r11);
- COPY(r12);
- COPY(r13);
- COPY(r14);
- COPY(r15);
-
- /* Kernel saves and restores only the CS segment register on signals,
- * which is the bare minimum needed to allow mixed 32/64-bit code.
- * App's signal handler can save/restore other segments if needed. */
- COPY_SEG_STRICT(cs);
-
- err |= __get_user(tmpflags, &sc->flags);
- regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
- regs->orig_ax = -1; /* disable syscall checks */
-
- err |= __get_user(buf, &sc->fpstate);
- err |= restore_i387_xstate(buf);
-
- err |= __get_user(*pax, &sc->ax);
- return err;
-}
-
-static long do_rt_sigreturn(struct pt_regs *regs)
-{
- struct rt_sigframe __user *frame;
- unsigned long ax;
- sigset_t set;
-
- frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long));
- 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, &ax))
- goto badframe;
-
- if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT)
- goto badframe;
-
- return ax;
-
-badframe:
- signal_fault(regs, frame, "rt_sigreturn");
- return 0;
-}
-
-asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
-{
- return do_rt_sigreturn(regs);
-}
-
-/*
- * Set up a signal frame.
- */
-
-static inline int
-setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
- unsigned long mask, struct task_struct *me)
-{
- int err = 0;
-
- err |= __put_user(regs->cs, &sc->cs);
- err |= __put_user(0, &sc->gs);
- err |= __put_user(0, &sc->fs);
-
- err |= __put_user(regs->di, &sc->di);
- err |= __put_user(regs->si, &sc->si);
- err |= __put_user(regs->bp, &sc->bp);
- err |= __put_user(regs->sp, &sc->sp);
- err |= __put_user(regs->bx, &sc->bx);
- err |= __put_user(regs->dx, &sc->dx);
- err |= __put_user(regs->cx, &sc->cx);
- err |= __put_user(regs->ax, &sc->ax);
- err |= __put_user(regs->r8, &sc->r8);
- err |= __put_user(regs->r9, &sc->r9);
- err |= __put_user(regs->r10, &sc->r10);
- err |= __put_user(regs->r11, &sc->r11);
- err |= __put_user(regs->r12, &sc->r12);
- err |= __put_user(regs->r13, &sc->r13);
- err |= __put_user(regs->r14, &sc->r14);
- err |= __put_user(regs->r15, &sc->r15);
- err |= __put_user(me->thread.trap_no, &sc->trapno);
- err |= __put_user(me->thread.error_code, &sc->err);
- err |= __put_user(regs->ip, &sc->ip);
- err |= __put_user(regs->flags, &sc->flags);
- err |= __put_user(mask, &sc->oldmask);
- err |= __put_user(me->thread.cr2, &sc->cr2);
-
- return err;
-}
-
-/*
- * Determine which stack to use..
- */
-
-static void __user *
-get_stack(struct k_sigaction *ka, struct pt_regs *regs, unsigned long size)
-{
- unsigned long sp;
-
- /* Default to using normal stack - redzone*/
- sp = regs->sp - 128;
-
- /* This is the X/Open sanctioned signal stack switching. */
- if (ka->sa.sa_flags & SA_ONSTACK) {
- if (sas_ss_flags(sp) == 0)
- sp = current->sas_ss_sp + current->sas_ss_size;
- }
-
- return (void __user *)round_down(sp - size, 64);
-}
-
-static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
- sigset_t *set, struct pt_regs *regs)
-{
- struct rt_sigframe __user *frame;
- void __user *fp = NULL;
- int err = 0;
- struct task_struct *me = current;
-
- if (used_math()) {
- fp = get_stack(ka, regs, sig_xstate_size);
- frame = (void __user *)round_down(
- (unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8;
-
- if (save_i387_xstate(fp) < 0)
- return -EFAULT;
- } else
- frame = get_stack(ka, regs, sizeof(struct rt_sigframe)) - 8;
-
- if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
- return -EFAULT;
-
- if (ka->sa.sa_flags & SA_SIGINFO) {
- if (copy_siginfo_to_user(&frame->info, info))
- return -EFAULT;
- }
-
- /* Create the ucontext. */
- if (cpu_has_xsave)
- err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
- else
- err |= __put_user(0, &frame->uc.uc_flags);
- err |= __put_user(0, &frame->uc.uc_link);
- err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
- err |= __put_user(sas_ss_flags(regs->sp),
- &frame->uc.uc_stack.ss_flags);
- err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
- err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0], me);
- err |= __put_user(fp, &frame->uc.uc_mcontext.fpstate);
- if (sizeof(*set) == 16) {
- __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
- __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
- } else
- err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
-
- /* Set up to return from userspace. If provided, use a stub
- already in userspace. */
- /* x86-64 should always use SA_RESTORER. */
- if (ka->sa.sa_flags & SA_RESTORER) {
- err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
- } else {
- /* could use a vstub here */
- return -EFAULT;
- }
-
- if (err)
- return -EFAULT;
-
- /* Set up registers for signal handler */
- regs->di = sig;
- /* In case the signal handler was declared without prototypes */
- regs->ax = 0;
-
- /* This also works for non SA_SIGINFO handlers because they expect the
- next argument after the signal number on the stack. */
- regs->si = (unsigned long)&frame->info;
- regs->dx = (unsigned long)&frame->uc;
- regs->ip = (unsigned long) ka->sa.sa_handler;
-
- regs->sp = (unsigned long)frame;
-
- /* Set up the CS register to run signal handlers in 64-bit mode,
- even if the handler happens to be interrupting 32-bit code. */
- regs->cs = __USER_CS;
-
- return 0;
-}
-
-/*
- * OK, we're invoking a handler
- */
-static int signr_convert(int sig)
-{
- return sig;
-}
-
-#ifdef CONFIG_IA32_EMULATION
-#define is_ia32 test_thread_flag(TIF_IA32)
-#else
-#define is_ia32 0
-#endif
-
-static int
-setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
- sigset_t *set, struct pt_regs *regs)
-{
- int usig = signr_convert(sig);
- int ret;
-
- /* Set up the stack frame */
- if (is_ia32) {
- if (ka->sa.sa_flags & SA_SIGINFO)
- ret = ia32_setup_rt_frame(usig, ka, info, set, regs);
- else
- ret = ia32_setup_frame(usig, ka, set, regs);
- } else
- ret = __setup_rt_frame(sig, ka, info, set, regs);
-
- if (ret) {
- force_sigsegv(sig, current);
- return -EFAULT;
- }
-
- return ret;
-}
-
-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 (syscall_get_nr(current, regs) >= 0) {
- /* If so, check system call restarting.. */
- switch (syscall_get_error(current, regs)) {
- case -ERESTART_RESTARTBLOCK:
- case -ERESTARTNOHAND:
- regs->ax = -EINTR;
- break;
-
- case -ERESTARTSYS:
- if (!(ka->sa.sa_flags & SA_RESTART)) {
- regs->ax = -EINTR;
- break;
- }
- /* fallthrough */
- case -ERESTARTNOINTR:
- regs->ax = regs->orig_ax;
- regs->ip -= 2;
- break;
- }
- }
-
- /*
- * If TF is set due to a debugger (TIF_FORCED_TF), clear the TF
- * flag so that register information in the sigcontext is correct.
- */
- if (unlikely(regs->flags & X86_EFLAGS_TF) &&
- likely(test_and_clear_thread_flag(TIF_FORCED_TF)))
- regs->flags &= ~X86_EFLAGS_TF;
-
- ret = setup_rt_frame(sig, ka, info, oldset, regs);
-
- if (ret)
- return ret;
-
-#ifdef CONFIG_X86_64
- /*
- * This has nothing to do with segment registers,
- * despite the name. This magic affects uaccess.h
- * macros' behavior. Reset it to the normal setting.
- */
- set_fs(USER_DS);
-#endif
-
- /*
- * Clear the direction flag as per the ABI for function entry.
- */
- regs->flags &= ~X86_EFLAGS_DF;
-
- /*
- * 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->flags &= ~X86_EFLAGS_TF;
-
- 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);
-
- tracehook_signal_handler(sig, info, ka, regs,
- test_thread_flag(TIF_SINGLESTEP));
-
- return 0;
-}
-
-#define NR_restart_syscall \
- test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall
-/*
- * 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 do_signal(struct pt_regs *regs)
-{
- struct k_sigaction ka;
- siginfo_t info;
- int signr;
- 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.
- * X86_32: vm86 regs switched out by assembly code before reaching
- * here, so testing against kernel CS suffices.
- */
- if (!user_mode(regs))
- return;
-
- if (current_thread_info()->status & TS_RESTORE_SIGMASK)
- oldset = &current->saved_sigmask;
- else
- oldset = &current->blocked;
-
- signr = get_signal_to_deliver(&info, &ka, regs, NULL);
- if (signr > 0) {
- /*
- * Re-enable any watchpoints before delivering the
- * signal to user space. The processor register will
- * have been cleared if the watchpoint triggered
- * inside the kernel.
- */
- if (current->thread.debugreg7)
- set_debugreg(current->thread.debugreg7, 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 TS_RESTORE_SIGMASK flag.
- */
- current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
- }
- return;
- }
-
- /* Did we come from a system call? */
- if (syscall_get_nr(current, regs) >= 0) {
- /* Restart the system call - no handlers present */
- switch (syscall_get_error(current, regs)) {
- case -ERESTARTNOHAND:
- case -ERESTARTSYS:
- case -ERESTARTNOINTR:
- regs->ax = regs->orig_ax;
- regs->ip -= 2;
- break;
-
- case -ERESTART_RESTARTBLOCK:
- regs->ax = NR_restart_syscall;
- regs->ip -= 2;
- break;
- }
- }
-
- /*
- * If there's no signal to deliver, we just put the saved sigmask
- * back.
- */
- if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
- current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
- sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
- }
-}
-
-/*
- * notification of userspace execution resumption
- * - triggered by the TIF_WORK_MASK flags
- */
-void
-do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
-{
-#if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE)
- /* notify userspace of pending MCEs */
- if (thread_info_flags & _TIF_MCE_NOTIFY)
- mce_notify_user();
-#endif /* CONFIG_X86_64 && CONFIG_X86_MCE */
-
- /* deal with pending signal delivery */
- if (thread_info_flags & _TIF_SIGPENDING)
- do_signal(regs);
-
- if (thread_info_flags & _TIF_NOTIFY_RESUME) {
- clear_thread_flag(TIF_NOTIFY_RESUME);
- tracehook_notify_resume(regs);
- }
-
-#ifdef CONFIG_X86_32
- clear_thread_flag(TIF_IRET);
-#endif /* CONFIG_X86_32 */
-}
-
-void signal_fault(struct pt_regs *regs, void __user *frame, char *where)
-{
- struct task_struct *me = current;
-
- if (show_unhandled_signals && printk_ratelimit()) {
- printk(KERN_INFO
- "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx",
- me->comm, me->pid, where, frame,
- regs->ip, regs->sp, regs->orig_ax);
- print_vma_addr(" in ", regs->ip);
- printk(KERN_CONT "\n");
- }
-
- force_sig(SIGSEGV, me);
-}