[IA64] signal : fix missing error checkings

Not all the return value of __copy_from_user and
__put_user is checked.This patch fixed it.
Signed-off-by: Shi Weihua <shiwh@cn.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/kernel/signal.c

@@ -98,7 +98,7 @@ restore_sigcontext (struct sigcontext __user *sc, struct sigscratch *scr)
 	if ((flags & IA64_SC_FLAG_FPH_VALID) != 0) {
 		struct ia64_psr *psr = ia64_psr(&scr->pt);
 
-		__copy_from_user(current->thread.fph, &sc->sc_fr[32], 96*16);
+		err |= __copy_from_user(current->thread.fph, &sc->sc_fr[32], 96*16);
 		psr->mfh = 0;	/* drop signal handler's fph contents... */
 		preempt_disable();
 		if (psr->dfh)
@@ -244,7 +244,7 @@ static long
 setup_sigcontext (struct sigcontext __user *sc, sigset_t *mask, struct sigscratch *scr)
 {
 	unsigned long flags = 0, ifs, cfm, nat;
-	long err;
+	long err = 0;
 
 	ifs = scr->pt.cr_ifs;
 
@@ -257,12 +257,12 @@ setup_sigcontext (struct sigcontext __user *sc, sigset_t *mask, struct sigscratc
 	ia64_flush_fph(current);
 	if ((current->thread.flags & IA64_THREAD_FPH_VALID)) {
 		flags |= IA64_SC_FLAG_FPH_VALID;
-		__copy_to_user(&sc->sc_fr[32], current->thread.fph, 96*16);
+		err = __copy_to_user(&sc->sc_fr[32], current->thread.fph, 96*16);
 	}
 
 	nat = ia64_get_scratch_nat_bits(&scr->pt, scr->scratch_unat);
 
-	err  = __put_user(flags, &sc->sc_flags);
+	err |= __put_user(flags, &sc->sc_flags);
 	err |= __put_user(nat, &sc->sc_nat);
 	err |= PUT_SIGSET(mask, &sc->sc_mask);
 	err |= __put_user(cfm, &sc->sc_cfm);