1 files changed, 35 insertions, 30 deletions

diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index c709868d28a5..7161d60e152d 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -463,12 +463,13 @@ static int ptrace_set_debugreg(struct task_struct *child,
 void ptrace_disable(struct task_struct *child)
 {
         user_disable_single_step(child);
+#ifdef TIF_SYSCALL_EMU
         clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+#endif
 }
 
 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 {
-        struct user * dummy = NULL;
         int i, ret;
         unsigned long __user *datap = (unsigned long __user *)data;
 
@@ -484,18 +485,17 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
                 unsigned long tmp;
 
                 ret = -EIO;
-                if ((addr & 3) || addr < 0 ||
-                    addr > sizeof(struct user) - 3)
+                if ((addr & (sizeof(data) - 1)) || addr < 0 ||
+                    addr >= sizeof(struct user))
                         break;
 
                 tmp = 0;  /* Default return condition */
-                if(addr < FRAME_SIZE*sizeof(long))
+                if (addr < sizeof(struct user_regs_struct))
                         tmp = getreg(child, addr);
-                if(addr >= (long) &dummy->u_debugreg[0] &&
-                   addr <= (long) &dummy->u_debugreg[7]){
-                        addr -= (long) &dummy->u_debugreg[0];
-                        addr = addr >> 2;
-                        tmp = ptrace_get_debugreg(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]);
+                        tmp = ptrace_get_debugreg(child, addr / sizeof(data));
                 }
                 ret = put_user(tmp, datap);
                 break;
@@ -509,34 +509,26 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 
         case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
                 ret = -EIO;
-                if ((addr & 3) || addr < 0 ||
-                    addr > sizeof(struct user) - 3)
+                if ((addr & (sizeof(data) - 1)) || addr < 0 ||
+                    addr >= sizeof(struct user))
                         break;
 
-                if (addr < FRAME_SIZE*sizeof(long)) {
+                if (addr < sizeof(struct user_regs_struct))
                         ret = putreg(child, addr, data);
-                        break;
+                else if (addr >= offsetof(struct user, u_debugreg[0]) &&
+                         addr <= offsetof(struct user, u_debugreg[7])) {
+                        addr -= offsetof(struct user, u_debugreg[0]);
+                        ret = ptrace_set_debugreg(child,
+                                                  addr / sizeof(data), data);
                 }
-                /* We need to be very careful here.  We implicitly
-                   want to modify a portion of the task_struct, and we
-                   have to be selective about what portions we allow someone
-                   to modify. */
-
-                  ret = -EIO;
-                  if(addr >= (long) &dummy->u_debugreg[0] &&
-                     addr <= (long) &dummy->u_debugreg[7]){
-                          addr -= (long) &dummy->u_debugreg;
-                          addr = addr >> 2;
-                          ret = ptrace_set_debugreg(child, addr, data);
-                  }
-                  break;
+                break;
 
         case PTRACE_GETREGS: { /* Get all gp regs from the child. */
-                if (!access_ok(VERIFY_WRITE, datap, FRAME_SIZE*sizeof(long))) {
+                if (!access_ok(VERIFY_WRITE, datap, sizeof(struct user_regs_struct))) {
                         ret = -EIO;
                         break;
                 }
-                for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
+                for (i = 0; i < sizeof(struct user_regs_struct); i += sizeof(long)) {
                         __put_user(getreg(child, i), datap);
                         datap++;
                 }
@@ -546,11 +538,11 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 
         case PTRACE_SETREGS: { /* Set all gp regs in the child. */
                 unsigned long tmp;
-                if (!access_ok(VERIFY_READ, datap, FRAME_SIZE*sizeof(long))) {
+                if (!access_ok(VERIFY_READ, datap, sizeof(struct user_regs_struct))) {
                         ret = -EIO;
                         break;
                 }
-                for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
+                for (i = 0; i < sizeof(struct user_regs_struct); i += sizeof(long)) {
                         __get_user(tmp, datap);
                         putreg(child, i, tmp);
                         datap++;
@@ -584,6 +576,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
                 break;
         }
 
+#ifdef CONFIG_X86_32
         case PTRACE_GETFPXREGS: { /* Get the child extended FPU state. */
                 if (!access_ok(VERIFY_WRITE, datap,
                                sizeof(struct user_fxsr_struct))) {
@@ -606,7 +599,9 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
                 ret = set_fpxregs(child, (struct user_fxsr_struct __user *)data);
                 break;
         }
+#endif
 
+#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
         case PTRACE_GET_THREAD_AREA:
                 if (addr < 0)
                         return -EIO;
@@ -620,6 +615,16 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
                 ret = do_set_thread_area(child, addr,
                                          (struct user_desc __user *) data, 0);
                 break;
+#endif
+
+#ifdef CONFIG_X86_64
+                /* 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;
+#endif
 
         default:
                 ret = ptrace_request(child, request, addr, data);