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-rw-r--r--arch/x86/um/ptrace_32.c273
1 files changed, 273 insertions, 0 deletions
diff --git a/arch/x86/um/ptrace_32.c b/arch/x86/um/ptrace_32.c
new file mode 100644
index 00000000000..3b949daa095
--- /dev/null
+++ b/arch/x86/um/ptrace_32.c
@@ -0,0 +1,273 @@
+/*
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/mm.h"
+#include "linux/sched.h"
+#include "asm/uaccess.h"
+#include "skas.h"
+
+extern int arch_switch_tls(struct task_struct *to);
+
+void arch_switch_to(struct task_struct *to)
+{
+ int err = arch_switch_tls(to);
+ if (!err)
+ return;
+
+ if (err != -EINVAL)
+ printk(KERN_WARNING "arch_switch_tls failed, errno %d, "
+ "not EINVAL\n", -err);
+ else
+ printk(KERN_WARNING "arch_switch_tls failed, errno = EINVAL\n");
+}
+
+int is_syscall(unsigned long addr)
+{
+ unsigned short instr;
+ int n;
+
+ n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
+ if (n) {
+ /* access_process_vm() grants access to vsyscall and stub,
+ * while copy_from_user doesn't. Maybe access_process_vm is
+ * slow, but that doesn't matter, since it will be called only
+ * in case of singlestepping, if copy_from_user failed.
+ */
+ n = access_process_vm(current, addr, &instr, sizeof(instr), 0);
+ if (n != sizeof(instr)) {
+ printk(KERN_ERR "is_syscall : failed to read "
+ "instruction from 0x%lx\n", addr);
+ return 1;
+ }
+ }
+ /* int 0x80 or sysenter */
+ return (instr == 0x80cd) || (instr == 0x340f);
+}
+
+/* determines which flags the user has access to. */
+/* 1 = access 0 = no access */
+#define FLAG_MASK 0x00044dd5
+
+static const int reg_offsets[] = {
+ [EBX] = HOST_BX,
+ [ECX] = HOST_CX,
+ [EDX] = HOST_DX,
+ [ESI] = HOST_SI,
+ [EDI] = HOST_DI,
+ [EBP] = HOST_BP,
+ [EAX] = HOST_AX,
+ [DS] = HOST_DS,
+ [ES] = HOST_ES,
+ [FS] = HOST_FS,
+ [GS] = HOST_GS,
+ [EIP] = HOST_IP,
+ [CS] = HOST_CS,
+ [EFL] = HOST_EFLAGS,
+ [UESP] = HOST_SP,
+ [SS] = HOST_SS,
+};
+
+int putreg(struct task_struct *child, int regno, unsigned long value)
+{
+ regno >>= 2;
+ switch (regno) {
+ case EBX:
+ case ECX:
+ case EDX:
+ case ESI:
+ case EDI:
+ case EBP:
+ case EAX:
+ case EIP:
+ case UESP:
+ break;
+ case FS:
+ if (value && (value & 3) != 3)
+ return -EIO;
+ break;
+ case GS:
+ if (value && (value & 3) != 3)
+ return -EIO;
+ break;
+ case DS:
+ case ES:
+ if (value && (value & 3) != 3)
+ return -EIO;
+ value &= 0xffff;
+ break;
+ case SS:
+ case CS:
+ if ((value & 3) != 3)
+ return -EIO;
+ value &= 0xffff;
+ break;
+ case EFL:
+ value &= FLAG_MASK;
+ child->thread.regs.regs.gp[HOST_EFLAGS] |= value;
+ return 0;
+ case ORIG_EAX:
+ child->thread.regs.regs.syscall = value;
+ return 0;
+ default :
+ panic("Bad register in putreg() : %d\n", regno);
+ }
+ child->thread.regs.regs.gp[reg_offsets[regno]] = value;
+ return 0;
+}
+
+int poke_user(struct task_struct *child, long addr, long data)
+{
+ if ((addr & 3) || addr < 0)
+ return -EIO;
+
+ if (addr < MAX_REG_OFFSET)
+ return putreg(child, addr, data);
+ else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
+ (addr <= offsetof(struct user, u_debugreg[7]))) {
+ addr -= offsetof(struct user, u_debugreg[0]);
+ addr = addr >> 2;
+ if ((addr == 4) || (addr == 5))
+ return -EIO;
+ child->thread.arch.debugregs[addr] = data;
+ return 0;
+ }
+ return -EIO;
+}
+
+unsigned long getreg(struct task_struct *child, int regno)
+{
+ unsigned long mask = ~0UL;
+
+ regno >>= 2;
+ switch (regno) {
+ case ORIG_EAX:
+ return child->thread.regs.regs.syscall;
+ case FS:
+ case GS:
+ case DS:
+ case ES:
+ case SS:
+ case CS:
+ mask = 0xffff;
+ break;
+ case EIP:
+ case UESP:
+ case EAX:
+ case EBX:
+ case ECX:
+ case EDX:
+ case ESI:
+ case EDI:
+ case EBP:
+ case EFL:
+ break;
+ default:
+ panic("Bad register in getreg() : %d\n", regno);
+ }
+ return mask & child->thread.regs.regs.gp[reg_offsets[regno]];
+}
+
+/* read the word at location addr in the USER area. */
+int peek_user(struct task_struct *child, long addr, long data)
+{
+ unsigned long tmp;
+
+ if ((addr & 3) || addr < 0)
+ return -EIO;
+
+ tmp = 0; /* Default return condition */
+ if (addr < MAX_REG_OFFSET) {
+ tmp = getreg(child, addr);
+ }
+ else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
+ (addr <= offsetof(struct user, u_debugreg[7]))) {
+ addr -= offsetof(struct user, u_debugreg[0]);
+ addr = addr >> 2;
+ tmp = child->thread.arch.debugregs[addr];
+ }
+ return put_user(tmp, (unsigned long __user *) data);
+}
+
+static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
+{
+ int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
+ struct user_i387_struct fpregs;
+
+ err = save_fp_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
+ if (err)
+ return err;
+
+ n = copy_to_user(buf, &fpregs, sizeof(fpregs));
+ if(n > 0)
+ return -EFAULT;
+
+ return n;
+}
+
+static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
+{
+ int n, cpu = ((struct thread_info *) child->stack)->cpu;
+ struct user_i387_struct fpregs;
+
+ n = copy_from_user(&fpregs, buf, sizeof(fpregs));
+ if (n > 0)
+ return -EFAULT;
+
+ return restore_fp_registers(userspace_pid[cpu],
+ (unsigned long *) &fpregs);
+}
+
+static int get_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
+{
+ int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
+ struct user_fxsr_struct fpregs;
+
+ err = save_fpx_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
+ if (err)
+ return err;
+
+ n = copy_to_user(buf, &fpregs, sizeof(fpregs));
+ if(n > 0)
+ return -EFAULT;
+
+ return n;
+}
+
+static int set_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
+{
+ int n, cpu = ((struct thread_info *) child->stack)->cpu;
+ struct user_fxsr_struct fpregs;
+
+ n = copy_from_user(&fpregs, buf, sizeof(fpregs));
+ if (n > 0)
+ return -EFAULT;
+
+ return restore_fpx_registers(userspace_pid[cpu],
+ (unsigned long *) &fpregs);
+}
+
+long subarch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ int ret = -EIO;
+ void __user *datap = (void __user *) data;
+ switch (request) {
+ case PTRACE_GETFPREGS: /* Get the child FPU state. */
+ ret = get_fpregs(datap, child);
+ break;
+ case PTRACE_SETFPREGS: /* Set the child FPU state. */
+ ret = set_fpregs(datap, child);
+ break;
+ case PTRACE_GETFPXREGS: /* Get the child FPU state. */
+ ret = get_fpxregs(datap, child);
+ break;
+ case PTRACE_SETFPXREGS: /* Set the child FPU state. */
+ ret = set_fpxregs(datap, child);
+ break;
+ default:
+ ret = -EIO;
+ }
+ return ret;
+}
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