x86: copy_thread: Don't nullify ->ptrace_bps twice

Both 32bit and 64bit versions of copy_thread() do memset(ptrace_bps)
twice for no reason, kill the 2nd memset().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20140902175733.GA21676@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

2 files changed, 1 insertions, 5 deletions

diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index c73b3c1a582b..8f3ebfe710d0 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -138,6 +138,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 
         p->thread.sp = (unsigned long) childregs;
         p->thread.sp0 = (unsigned long) (childregs+1);
+        memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
 
         if (unlikely(p->flags & PF_KTHREAD)) {
                 /* kernel thread */
@@ -153,7 +154,6 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
                 childregs->cs = __KERNEL_CS | get_kernel_rpl();
                 childregs->flags = X86_EFLAGS_IF | X86_EFLAGS_FIXED;
                 p->thread.io_bitmap_ptr = NULL;
-                memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
                 return 0;
         }
         *childregs = *current_pt_regs();
@@ -168,8 +168,6 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
         tsk = current;
         err = -ENOMEM;
 
-        memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
-
         if (unlikely(test_tsk_thread_flag(tsk, TIF_IO_BITMAP))) {
                 p->thread.io_bitmap_ptr = kmemdup(tsk->thread.io_bitmap_ptr,
                                                 IO_BITMAP_BYTES, GFP_KERNEL);
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 593257def776..3ed4a68d4013 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -192,8 +192,6 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
                 childregs->sp = sp;
 
         err = -ENOMEM;
-        memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
-
         if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) {
                 p->thread.io_bitmap_ptr = kmemdup(me->thread.io_bitmap_ptr,
                                                   IO_BITMAP_BYTES, GFP_KERNEL);