ALSA: sb: check get_user() return value

get_user() may fail, if so return -EFAULT.

[Fixed one missing place by tiwai]
Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/isa/sb/emu8000_pcm.c

@@ -433,7 +433,8 @@ static int emu8k_transfer_block(struct snd_emu8000 *emu, int offset, unsigned sh
 	while (count > 0) {
 		unsigned short sval;
 		CHECK_SCHEDULER();
-		get_user(sval, buf);
+		if (get_user(sval, buf))
+			return -EFAULT;
 		EMU8000_SMLD_WRITE(emu, sval);
 		buf++;
 		count--;
@@ -525,12 +526,14 @@ static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
 	while (count-- > 0) {
 		unsigned short sval;
 		CHECK_SCHEDULER();
-		get_user(sval, buf);
+		if (get_user(sval, buf))
+			return -EFAULT;
 		EMU8000_SMLD_WRITE(emu, sval);
 		buf++;
 		if (rec->voices > 1) {
 			CHECK_SCHEDULER();
-			get_user(sval, buf);
+			if (get_user(sval, buf))
+				return -EFAULT;
 			EMU8000_SMRD_WRITE(emu, sval);
 			buf++;
 		}