x86, ptrace: change BTS GET ptrace interface

[firefly-linux-kernel-4.4.55.git] / arch / x86 / kernel / ptrace.c

diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index ec86abaab530fb45e0a5ef15ca65c9fd16836442..3e78c124e2d21d0486729dc1ebdd5777340ea89b 100644 (file)
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -479,26 +479,33 @@ static int ptrace_bts_get_buffer_size(struct task_struct *child)
        return ds_get_bts_size((void *)child->thread.ds_area_msr);
 }
 
-static int ptrace_bts_get_index(struct task_struct *child)
-{
-       if (!child->thread.ds_area_msr)
-               return -ENXIO;
-
-       return ds_get_bts_index((void *)child->thread.ds_area_msr);
-}
-
 static int ptrace_bts_read_record(struct task_struct *child,
                                  long index,
                                  struct bts_struct __user *out)
 {
        struct bts_struct ret;
        int retval;
+       int bts_size;
+       int bts_index;
 
        if (!child->thread.ds_area_msr)
                return -ENXIO;
 
+       if (index < 0)
+               return -EINVAL;
+
+       bts_size = ds_get_bts_size((void *)child->thread.ds_area_msr);
+       if (bts_size <= index)
+               return -EINVAL;
+
+       /* translate the ptrace bts index into the ds bts index */
+       bts_index = ds_get_bts_index((void *)child->thread.ds_area_msr);
+       bts_index -= (index + 1);
+       if (bts_index < 0)
+               bts_index += bts_size;
+
        retval = ds_read_bts((void *)child->thread.ds_area_msr,
-                            index, &ret);
+                            bts_index, &ret);
        if (retval)
                return retval;
 
@@ -813,10 +820,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
                ret = ptrace_bts_get_buffer_size(child);
                break;
 
-       case PTRACE_BTS_GET_INDEX:
-               ret = ptrace_bts_get_index(child);
-               break;
-
        case PTRACE_BTS_READ_RECORD:
                ret = ptrace_bts_read_record
                        (child, data,
@@ -1017,7 +1020,6 @@ asmlinkage long sys32_ptrace(long request, u32 pid, u32 addr, u32 data)
        case PTRACE_BTS_MAX_BUFFER_SIZE:
        case PTRACE_BTS_ALLOCATE_BUFFER:
        case PTRACE_BTS_GET_BUFFER_SIZE:
-       case PTRACE_BTS_GET_INDEX:
        case PTRACE_BTS_READ_RECORD:
        case PTRACE_BTS_CONFIG:
        case PTRACE_BTS_STATUS: