x86: use sizeof(long) to unify signal_32|64.c

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 9eb23fb..47c85e6 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -214,11 +214,12 @@
 
 asmlinkage int sys_rt_sigreturn(unsigned long __unused)
 {
-	struct pt_regs *regs = (struct pt_regs *) &__unused;
-	struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(regs->sp - 4);
+	struct pt_regs *regs = (struct pt_regs *)&__unused;
+	struct rt_sigframe __user *frame;
 	sigset_t set;
 	int ax;
 
+	frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long));
 	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
 		goto badframe;
 	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))