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>

diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index c73b3c1..8f3ebfe 100644 (file)
--- 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 593257d..3ed4a68 100644 (file)
--- 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);