From: Takashi Iwai <tiwai@suse.de>
Date: Wed, 25 Jul 2018 14:34:12 +0000 (+0200)
Subject: ALSA: seq: Fix poll() error return
X-Git-Tag: v4.17.18~18
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=99747622f957caff1e6064390728fa3e1c324984;p=thirdparty%2Fkernel%2Fstable.git

ALSA: seq: Fix poll() error return

commit a49a71f6e25da2acc637fcd31e73debd96ca18f8 upstream.

The sanity checks in ALSA sequencer and OSS sequencer emulation codes
return falsely -ENXIO from poll callback.  They should be EPOLLERR
instead.

This was caught thanks to the recent change to the return value.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/sound/core/seq/oss/seq_oss.c b/sound/core/seq/oss/seq_oss.c
index 5f64d0d883200..e1f44fc868856 100644
--- a/sound/core/seq/oss/seq_oss.c
+++ b/sound/core/seq/oss/seq_oss.c
@@ -203,7 +203,7 @@ odev_poll(struct file *file, poll_table * wait)
 	struct seq_oss_devinfo *dp;
 	dp = file->private_data;
 	if (snd_BUG_ON(!dp))
-		return -ENXIO;
+		return EPOLLERR;
 	return snd_seq_oss_poll(dp, file, wait);
 }
 
diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 61a07fe34cd27..ee8d0d86f0df2 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -1101,7 +1101,7 @@ static __poll_t snd_seq_poll(struct file *file, poll_table * wait)
 
 	/* check client structures are in place */
 	if (snd_BUG_ON(!client))
-		return -ENXIO;
+		return EPOLLERR;
 
 	if ((snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT) &&
 	    client->data.user.fifo) {