x86_64: move kernel

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 627 insertions, 0 deletions

diff --git a/arch/x86/kernel/ptrace_64.c b/arch/x86/kernel/ptrace_64.c
new file mode 100644
index 000000000000..eea3702427b4
--- /dev/null
+++ b/arch/x86/kernel/ptrace_64.c
@@ -0,0 +1,627 @@
+/* ptrace.c */
+/* By Ross Biro 1/23/92 */
+/*
+ * Pentium III FXSR, SSE support
+ *      Gareth Hughes <gareth@valinux.com>, May 2000
+ * 
+ * x86-64 port 2000-2002 Andi Kleen
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/security.h>
+#include <linux/audit.h>
+#include <linux/seccomp.h>
+#include <linux/signal.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/i387.h>
+#include <asm/debugreg.h>
+#include <asm/ldt.h>
+#include <asm/desc.h>
+#include <asm/proto.h>
+#include <asm/ia32.h>
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+/*
+ * Determines which flags the user has access to [1 = access, 0 = no access].
+ * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), IOPL(12-13), IF(9).
+ * Also masks reserved bits (63-22, 15, 5, 3, 1).
+ */
+#define FLAG_MASK 0x54dd5UL
+
+/* set's the trap flag. */
+#define TRAP_FLAG 0x100UL
+
+/*
+ * eflags and offset of eflags on child stack..
+ */
+#define EFLAGS offsetof(struct pt_regs, eflags)
+#define EFL_OFFSET ((int)(EFLAGS-sizeof(struct pt_regs)))
+
+/*
+ * this routine will get a word off of the processes privileged stack. 
+ * the offset is how far from the base addr as stored in the TSS.  
+ * this routine assumes that all the privileged stacks are in our
+ * data space.
+ */   
+static inline unsigned long get_stack_long(struct task_struct *task, int offset)
+{
+        unsigned char *stack;
+
+        stack = (unsigned char *)task->thread.rsp0;
+        stack += offset;
+        return (*((unsigned long *)stack));
+}
+
+/*
+ * this routine will put a word on the processes privileged stack. 
+ * the offset is how far from the base addr as stored in the TSS.  
+ * this routine assumes that all the privileged stacks are in our
+ * data space.
+ */
+static inline long put_stack_long(struct task_struct *task, int offset,
+        unsigned long data)
+{
+        unsigned char * stack;
+
+        stack = (unsigned char *) task->thread.rsp0;
+        stack += offset;
+        *(unsigned long *) stack = data;
+        return 0;
+}
+
+#define LDT_SEGMENT 4
+
+unsigned long convert_rip_to_linear(struct task_struct *child, struct pt_regs *regs)
+{
+        unsigned long addr, seg;
+
+        addr = regs->rip;
+        seg = regs->cs & 0xffff;
+
+        /*
+         * We'll assume that the code segments in the GDT
+         * are all zero-based. That is largely true: the
+         * TLS segments are used for data, and the PNPBIOS
+         * and APM bios ones we just ignore here.
+         */
+        if (seg & LDT_SEGMENT) {
+                u32 *desc;
+                unsigned long base;
+
+                seg &= ~7UL;
+
+                down(&child->mm->context.sem);
+                if (unlikely((seg >> 3) >= child->mm->context.size))
+                        addr = -1L; /* bogus selector, access would fault */
+                else {
+                        desc = child->mm->context.ldt + seg;
+                        base = ((desc[0] >> 16) |
+                                ((desc[1] & 0xff) << 16) |
+                                (desc[1] & 0xff000000));
+
+                        /* 16-bit code segment? */
+                        if (!((desc[1] >> 22) & 1))
+                                addr &= 0xffff;
+                        addr += base;
+                }
+                up(&child->mm->context.sem);
+        }
+
+        return addr;
+}
+
+static int is_setting_trap_flag(struct task_struct *child, struct pt_regs *regs)
+{
+        int i, copied;
+        unsigned char opcode[15];
+        unsigned long addr = convert_rip_to_linear(child, regs);
+
+        copied = access_process_vm(child, addr, opcode, sizeof(opcode), 0);
+        for (i = 0; i < copied; i++) {
+                switch (opcode[i]) {
+                /* popf and iret */
+                case 0x9d: case 0xcf:
+                        return 1;
+
+                        /* CHECKME: 64 65 */
+
+                /* opcode and address size prefixes */
+                case 0x66: case 0x67:
+                        continue;
+                /* irrelevant prefixes (segment overrides and repeats) */
+                case 0x26: case 0x2e:
+                case 0x36: case 0x3e:
+                case 0x64: case 0x65:
+                case 0xf2: case 0xf3:
+                        continue;
+
+                case 0x40 ... 0x4f:
+                        if (regs->cs != __USER_CS)
+                                /* 32-bit mode: register increment */
+                                return 0;
+                        /* 64-bit mode: REX prefix */
+                        continue;
+
+                        /* CHECKME: f2, f3 */
+
+                /*
+                 * pushf: NOTE! We should probably not let
+                 * the user see the TF bit being set. But
+                 * it's more pain than it's worth to avoid
+                 * it, and a debugger could emulate this
+                 * all in user space if it _really_ cares.
+                 */
+                case 0x9c:
+                default:
+                        return 0;
+                }
+        }
+        return 0;
+}
+
+static void set_singlestep(struct task_struct *child)
+{
+        struct pt_regs *regs = task_pt_regs(child);
+
+        /*
+         * Always set TIF_SINGLESTEP - this guarantees that
+         * we single-step system calls etc..  This will also
+         * cause us to set TF when returning to user mode.
+         */
+        set_tsk_thread_flag(child, TIF_SINGLESTEP);
+
+        /*
+         * If TF was already set, don't do anything else
+         */
+        if (regs->eflags & TRAP_FLAG)
+                return;
+
+        /* Set TF on the kernel stack.. */
+        regs->eflags |= TRAP_FLAG;
+
+        /*
+         * ..but if TF is changed by the instruction we will trace,
+         * don't mark it as being "us" that set it, so that we
+         * won't clear it by hand later.
+         */
+        if (is_setting_trap_flag(child, regs))
+                return;
+
+        child->ptrace |= PT_DTRACE;
+}
+
+static void clear_singlestep(struct task_struct *child)
+{
+        /* Always clear TIF_SINGLESTEP... */
+        clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+
+        /* But touch TF only if it was set by us.. */
+        if (child->ptrace & PT_DTRACE) {
+                struct pt_regs *regs = task_pt_regs(child);
+                regs->eflags &= ~TRAP_FLAG;
+                child->ptrace &= ~PT_DTRACE;
+        }
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure the single step bit is not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{ 
+        clear_singlestep(child);
+}
+
+static int putreg(struct task_struct *child,
+        unsigned long regno, unsigned long value)
+{
+        unsigned long tmp; 
+        
+        switch (regno) {
+                case offsetof(struct user_regs_struct,fs):
+                        if (value && (value & 3) != 3)
+                                return -EIO;
+                        child->thread.fsindex = value & 0xffff; 
+                        return 0;
+                case offsetof(struct user_regs_struct,gs):
+                        if (value && (value & 3) != 3)
+                                return -EIO;
+                        child->thread.gsindex = value & 0xffff;
+                        return 0;
+                case offsetof(struct user_regs_struct,ds):
+                        if (value && (value & 3) != 3)
+                                return -EIO;
+                        child->thread.ds = value & 0xffff;
+                        return 0;
+                case offsetof(struct user_regs_struct,es): 
+                        if (value && (value & 3) != 3)
+                                return -EIO;
+                        child->thread.es = value & 0xffff;
+                        return 0;
+                case offsetof(struct user_regs_struct,ss):
+                        if ((value & 3) != 3)
+                                return -EIO;
+                        value &= 0xffff;
+                        return 0;
+                case offsetof(struct user_regs_struct,fs_base):
+                        if (value >= TASK_SIZE_OF(child))
+                                return -EIO;
+                        child->thread.fs = value;
+                        return 0;
+                case offsetof(struct user_regs_struct,gs_base):
+                        if (value >= TASK_SIZE_OF(child))
+                                return -EIO;
+                        child->thread.gs = value;
+                        return 0;
+                case offsetof(struct user_regs_struct, eflags):
+                        value &= FLAG_MASK;
+                        tmp = get_stack_long(child, EFL_OFFSET); 
+                        tmp &= ~FLAG_MASK; 
+                        value |= tmp;
+                        break;
+                case offsetof(struct user_regs_struct,cs): 
+                        if ((value & 3) != 3)
+                                return -EIO;
+                        value &= 0xffff;
+                        break;
+        }
+        put_stack_long(child, regno - sizeof(struct pt_regs), value);
+        return 0;
+}
+
+static unsigned long getreg(struct task_struct *child, unsigned long regno)
+{
+        unsigned long val;
+        switch (regno) {
+                case offsetof(struct user_regs_struct, fs):
+                        return child->thread.fsindex;
+                case offsetof(struct user_regs_struct, gs):
+                        return child->thread.gsindex;
+                case offsetof(struct user_regs_struct, ds):
+                        return child->thread.ds;
+                case offsetof(struct user_regs_struct, es):
+                        return child->thread.es; 
+                case offsetof(struct user_regs_struct, fs_base):
+                        return child->thread.fs;
+                case offsetof(struct user_regs_struct, gs_base):
+                        return child->thread.gs;
+                default:
+                        regno = regno - sizeof(struct pt_regs);
+                        val = get_stack_long(child, regno);
+                        if (test_tsk_thread_flag(child, TIF_IA32))
+                                val &= 0xffffffff;
+                        return val;
+        }
+
+}
+
+long arch_ptrace(struct task_struct *child, long request, long addr, long data)
+{
+        long i, ret;
+        unsigned ui;
+
+        switch (request) {
+        /* when I and D space are separate, these will need to be fixed. */
+        case PTRACE_PEEKTEXT: /* read word at location addr. */ 
+        case PTRACE_PEEKDATA:
+                ret = generic_ptrace_peekdata(child, addr, data);
+                break;
+
+        /* read the word at location addr in the USER area. */
+        case PTRACE_PEEKUSR: {
+                unsigned long tmp;
+
+                ret = -EIO;
+                if ((addr & 7) ||
+                    addr > sizeof(struct user) - 7)
+                        break;
+
+                switch (addr) { 
+                case 0 ... sizeof(struct user_regs_struct) - sizeof(long):
+                        tmp = getreg(child, addr);
+                        break;
+                case offsetof(struct user, u_debugreg[0]):
+                        tmp = child->thread.debugreg0;
+                        break;
+                case offsetof(struct user, u_debugreg[1]):
+                        tmp = child->thread.debugreg1;
+                        break;
+                case offsetof(struct user, u_debugreg[2]):
+                        tmp = child->thread.debugreg2;
+                        break;
+                case offsetof(struct user, u_debugreg[3]):
+                        tmp = child->thread.debugreg3;
+                        break;
+                case offsetof(struct user, u_debugreg[6]):
+                        tmp = child->thread.debugreg6;
+                        break;
+                case offsetof(struct user, u_debugreg[7]):
+                        tmp = child->thread.debugreg7;
+                        break;
+                default:
+                        tmp = 0;
+                        break;
+                }
+                ret = put_user(tmp,(unsigned long __user *) data);
+                break;
+        }
+
+        /* when I and D space are separate, this will have to be fixed. */
+        case PTRACE_POKETEXT: /* write the word at location addr. */
+        case PTRACE_POKEDATA:
+                ret = generic_ptrace_pokedata(child, addr, data);
+                break;
+
+        case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
+        {
+                int dsize = test_tsk_thread_flag(child, TIF_IA32) ? 3 : 7;
+                ret = -EIO;
+                if ((addr & 7) ||
+                    addr > sizeof(struct user) - 7)
+                        break;
+
+                switch (addr) { 
+                case 0 ... sizeof(struct user_regs_struct) - sizeof(long):
+                        ret = putreg(child, addr, data);
+                        break;
+                /* Disallows to set a breakpoint into the vsyscall */
+                case offsetof(struct user, u_debugreg[0]):
+                        if (data >= TASK_SIZE_OF(child) - dsize) break;
+                        child->thread.debugreg0 = data;
+                        ret = 0;
+                        break;
+                case offsetof(struct user, u_debugreg[1]):
+                        if (data >= TASK_SIZE_OF(child) - dsize) break;
+                        child->thread.debugreg1 = data;
+                        ret = 0;
+                        break;
+                case offsetof(struct user, u_debugreg[2]):
+                        if (data >= TASK_SIZE_OF(child) - dsize) break;
+                        child->thread.debugreg2 = data;
+                        ret = 0;
+                        break;
+                case offsetof(struct user, u_debugreg[3]):
+                        if (data >= TASK_SIZE_OF(child) - dsize) break;
+                        child->thread.debugreg3 = data;
+                        ret = 0;
+                        break;
+                case offsetof(struct user, u_debugreg[6]):
+                                  if (data >> 32)
+                                break; 
+                        child->thread.debugreg6 = data;
+                        ret = 0;
+                        break;
+                case offsetof(struct user, u_debugreg[7]):
+                        /* See arch/i386/kernel/ptrace.c for an explanation of
+                         * this awkward check.*/
+                        data &= ~DR_CONTROL_RESERVED;
+                        for(i=0; i<4; i++)
+                                if ((0x5554 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
+                                        break;
+                        if (i == 4) {
+                          child->thread.debugreg7 = data;
+                          if (data)
+                                set_tsk_thread_flag(child, TIF_DEBUG);
+                          else
+                                clear_tsk_thread_flag(child, TIF_DEBUG);
+                          ret = 0;
+                        }
+                  break;
+                }
+                break;
+        }
+        case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
+        case PTRACE_CONT:    /* restart after signal. */
+
+                ret = -EIO;
+                if (!valid_signal(data))
+                        break;
+                if (request == PTRACE_SYSCALL)
+                        set_tsk_thread_flag(child,TIF_SYSCALL_TRACE);
+                else
+                        clear_tsk_thread_flag(child,TIF_SYSCALL_TRACE);
+                clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+                child->exit_code = data;
+                /* make sure the single step bit is not set. */
+                clear_singlestep(child);
+                wake_up_process(child);
+                ret = 0;
+                break;
+
+#ifdef CONFIG_IA32_EMULATION
+                /* This makes only sense with 32bit programs. Allow a
+                   64bit debugger to fully examine them too. Better
+                   don't use it against 64bit processes, use
+                   PTRACE_ARCH_PRCTL instead. */
+        case PTRACE_SET_THREAD_AREA: {
+                struct user_desc __user *p;
+                int old; 
+                p = (struct user_desc __user *)data;
+                get_user(old,  &p->entry_number); 
+                put_user(addr, &p->entry_number);
+                ret = do_set_thread_area(&child->thread, p);
+                put_user(old,  &p->entry_number); 
+                break;
+        case PTRACE_GET_THREAD_AREA:
+                p = (struct user_desc __user *)data;
+                get_user(old,  &p->entry_number); 
+                put_user(addr, &p->entry_number);
+                ret = do_get_thread_area(&child->thread, p);
+                put_user(old,  &p->entry_number); 
+                break;
+        } 
+#endif
+                /* normal 64bit interface to access TLS data. 
+                   Works just like arch_prctl, except that the arguments
+                   are reversed. */
+        case PTRACE_ARCH_PRCTL: 
+                ret = do_arch_prctl(child, data, addr);
+                break;
+
+/*
+ * make the child exit.  Best I can do is send it a sigkill. 
+ * perhaps it should be put in the status that it wants to 
+ * exit.
+ */
+        case PTRACE_KILL:
+                ret = 0;
+                if (child->exit_state == EXIT_ZOMBIE)   /* already dead */
+                        break;
+                clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+                child->exit_code = SIGKILL;
+                /* make sure the single step bit is not set. */
+                clear_singlestep(child);
+                wake_up_process(child);
+                break;
+
+        case PTRACE_SINGLESTEP:    /* set the trap flag. */
+                ret = -EIO;
+                if (!valid_signal(data))
+                        break;
+                clear_tsk_thread_flag(child,TIF_SYSCALL_TRACE);
+                set_singlestep(child);
+                child->exit_code = data;
+                /* give it a chance to run. */
+                wake_up_process(child);
+                ret = 0;
+                break;
+
+        case PTRACE_DETACH:
+                /* detach a process that was attached. */
+                ret = ptrace_detach(child, data);
+                break;
+
+        case PTRACE_GETREGS: { /* Get all gp regs from the child. */
+                if (!access_ok(VERIFY_WRITE, (unsigned __user *)data,
+                               sizeof(struct user_regs_struct))) {
+                        ret = -EIO;
+                        break;
+                }
+                ret = 0;
+                for (ui = 0; ui < sizeof(struct user_regs_struct); ui += sizeof(long)) {
+                        ret |= __put_user(getreg(child, ui),(unsigned long __user *) data);
+                        data += sizeof(long);
+                }
+                break;
+        }
+
+        case PTRACE_SETREGS: { /* Set all gp regs in the child. */
+                unsigned long tmp;
+                if (!access_ok(VERIFY_READ, (unsigned __user *)data,
+                               sizeof(struct user_regs_struct))) {
+                        ret = -EIO;
+                        break;
+                }
+                ret = 0;
+                for (ui = 0; ui < sizeof(struct user_regs_struct); ui += sizeof(long)) {
+                        ret = __get_user(tmp, (unsigned long __user *) data);
+                        if (ret)
+                                break;
+                        ret = putreg(child, ui, tmp);
+                        if (ret)
+                                break;
+                        data += sizeof(long);
+                }
+                break;
+        }
+
+        case PTRACE_GETFPREGS: { /* Get the child extended FPU state. */
+                if (!access_ok(VERIFY_WRITE, (unsigned __user *)data,
+                               sizeof(struct user_i387_struct))) {
+                        ret = -EIO;
+                        break;
+                }
+                ret = get_fpregs((struct user_i387_struct __user *)data, child);
+                break;
+        }
+
+        case PTRACE_SETFPREGS: { /* Set the child extended FPU state. */
+                if (!access_ok(VERIFY_READ, (unsigned __user *)data,
+                               sizeof(struct user_i387_struct))) {
+                        ret = -EIO;
+                        break;
+                }
+                set_stopped_child_used_math(child);
+                ret = set_fpregs(child, (struct user_i387_struct __user *)data);
+                break;
+        }
+
+        default:
+                ret = ptrace_request(child, request, addr, data);
+                break;
+        }
+        return ret;
+}
+
+static void syscall_trace(struct pt_regs *regs)
+{
+
+#if 0
+        printk("trace %s rip %lx rsp %lx rax %d origrax %d caller %lx tiflags %x ptrace %x\n",
+               current->comm,
+               regs->rip, regs->rsp, regs->rax, regs->orig_rax, __builtin_return_address(0),
+               current_thread_info()->flags, current->ptrace); 
+#endif
+
+        ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
+                                ? 0x80 : 0));
+        /*
+         * this isn't the same as continuing with a signal, but it will do
+         * for normal use.  strace only continues with a signal if the
+         * stopping signal is not SIGTRAP.  -brl
+         */
+        if (current->exit_code) {
+                send_sig(current->exit_code, current, 1);
+                current->exit_code = 0;
+        }
+}
+
+asmlinkage void syscall_trace_enter(struct pt_regs *regs)
+{
+        /* do the secure computing check first */
+        secure_computing(regs->orig_rax);
+
+        if (test_thread_flag(TIF_SYSCALL_TRACE)
+            && (current->ptrace & PT_PTRACED))
+                syscall_trace(regs);
+
+        if (unlikely(current->audit_context)) {
+                if (test_thread_flag(TIF_IA32)) {
+                        audit_syscall_entry(AUDIT_ARCH_I386,
+                                            regs->orig_rax,
+                                            regs->rbx, regs->rcx,
+                                            regs->rdx, regs->rsi);
+                } else {
+                        audit_syscall_entry(AUDIT_ARCH_X86_64,
+                                            regs->orig_rax,
+                                            regs->rdi, regs->rsi,
+                                            regs->rdx, regs->r10);
+                }
+        }
+}
+
+asmlinkage void syscall_trace_leave(struct pt_regs *regs)
+{
+        if (unlikely(current->audit_context))
+                audit_syscall_exit(AUDITSC_RESULT(regs->rax), regs->rax);
+
+        if ((test_thread_flag(TIF_SYSCALL_TRACE)
+             || test_thread_flag(TIF_SINGLESTEP))
+            && (current->ptrace & PT_PTRACED))
+                syscall_trace(regs);
+}