x86/signals: ia32_signal.c: add __user casts to fix sparse warnings

Fix the following sparse warnings by adding appropriate __user
casts and annotations:

  ia32_signal.c:165:38: warning: incorrect type in argument 1 (different address spaces)
   ia32_signal.c:165:38:    expected struct sigaltstack const [noderef] [usertype] <asn:1>*<noident>
  ia32_signal.c:165:38:    got struct sigaltstack *
  [...]
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/1346621506-30857-4-git-send-email-minipli@googlemail.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/ia32/ia32_signal.c

@@ -162,7 +162,8 @@ asmlinkage long sys32_sigaltstack(const stack_ia32_t __user *uss_ptr,
 	}
 	seg = get_fs();
 	set_fs(KERNEL_DS);
-	ret = do_sigaltstack(uss_ptr ? &uss : NULL, &uoss, regs->sp);
+	ret = do_sigaltstack((stack_t __force __user *) (uss_ptr ? &uss : NULL),
+			     (stack_t __force __user *) &uoss, regs->sp);
 	set_fs(seg);
 	if (ret >= 0 && uoss_ptr)  {
 		if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(stack_ia32_t)))
@@ -361,7 +362,7 @@ static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc,
  */
 static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
 				 size_t frame_size,
-				 void **fpstate)
+				 void __user **fpstate)
 {
 	unsigned long sp;
 
@@ -382,7 +383,7 @@ static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
 
 	if (used_math()) {
 		sp = sp - sig_xstate_ia32_size;
-		*fpstate = (struct _fpstate_ia32 *) sp;
+		*fpstate = (struct _fpstate_ia32 __user *) sp;
 		if (save_i387_xstate_ia32(*fpstate) < 0)
 			return (void __user *) -1L;
 	}
@@ -448,7 +449,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
 		 * These are actually not used anymore, but left because some
 		 * gdb versions depend on them as a marker.
 		 */
-		put_user_ex(*((u64 *)&code), (u64 *)frame->retcode);
+		put_user_ex(*((u64 *)&code), (u64 __user *)frame->retcode);
 	} put_user_catch(err);
 
 	if (err)
@@ -529,7 +530,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 		 * Not actually used anymore, but left because some gdb
 		 * versions need it.
 		 */
-		put_user_ex(*((u64 *)&code), (u64 *)frame->retcode);
+		put_user_ex(*((u64 *)&code), (u64 __user *)frame->retcode);
 	} put_user_catch(err);
 
 	if (err)