From: Colin Ian King <colin.king@canonical.com>
Date: Thu, 27 Jun 2019 16:43:08 +0000 (+0100)
Subject: ALSA: usb-audio: fix sign unintended sign extension on left shifts
X-Git-Tag: v4.4.185~8
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=52e0b9fcd6f60cf66a30d33216aad6148bdaebb7;p=thirdparty%2Fkernel%2Fstable.git

ALSA: usb-audio: fix sign unintended sign extension on left shifts

commit 2acf5a3e6e9371e63c9e4ff54d84d08f630467a0 upstream.

There are a couple of left shifts of unsigned 8 bit values that
first get promoted to signed ints and hence get sign extended
on the shift if the top bit of the 8 bit values are set. Fix
this by casting the 8 bit values to unsigned ints to stop the
unintentional sign extension.

Addresses-Coverity: ("Unintended sign extension")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
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/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c
index 5d2fc5f58bfe5..f4fd9548c5291 100644
--- a/sound/usb/mixer_quirks.c
+++ b/sound/usb/mixer_quirks.c
@@ -753,7 +753,7 @@ static int snd_ni_control_init_val(struct usb_mixer_interface *mixer,
 		return err;
 	}
 
-	kctl->private_value |= (value << 24);
+	kctl->private_value |= ((unsigned int)value << 24);
 	return 0;
 }
 
@@ -914,7 +914,7 @@ static int snd_ftu_eff_switch_init(struct usb_mixer_interface *mixer,
 	if (err < 0)
 		return err;
 
-	kctl->private_value |= value[0] << 24;
+	kctl->private_value |= (unsigned int)value[0] << 24;
 	return 0;
 }