From 5fb45414ae03421255593fd5556aa2d1d82303aa Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Tue, 6 Apr 2021 13:35:34 +0200
Subject: [PATCH] ALSA: usb-audio: Add error checks for usb_driver_claim_interface() calls
Git-commit: 5fb45414ae03421255593fd5556aa2d1d82303aa
Patch-mainline: v5.13-rc1
References: git-fixes

There are a few calls of usb_driver_claim_interface() but all of those
miss the proper error checks, as reported by Coverity.  This patch
adds those missing checks.

Along with it, replace the magic pointer with -1 with a constant
USB_AUDIO_IFACE_UNUSED for better readability.

Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-coverity-id: 1475943 ("Error handling issues")
Addresses-coverity-id: 1475944 ("Error handling issues")
Addresses-coverity-id: 1475945 ("Error handling issues")
Fixes: b1ce7ba619d9 ("ALSA: usb-audio: claim autodetected PCM interfaces all at once")
Fixes: e5779998bf8b ("ALSA: usb-audio: refactor code")
Link: https://lore.kernel.org/r/202104051059.FB7F3016@keescook
Link: https://lore.kernel.org/r/20210406113534.30455-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

---
 sound/usb/card.c     |   14 +++++++-------
 sound/usb/quirks.c   |   16 ++++++++++++----
 sound/usb/usbaudio.h |    2 ++
 3 files changed, 21 insertions(+), 11 deletions(-)

--- a/sound/usb/card.c
+++ b/sound/usb/card.c
@@ -195,9 +195,8 @@ static int snd_usb_create_stream(struct
 				ctrlif, interface);
 			return -EINVAL;
 		}
-		usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
-
-		return 0;
+		return usb_driver_claim_interface(&usb_audio_driver, iface,
+						  USB_AUDIO_IFACE_UNUSED);
 	}
 
 	if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
@@ -217,7 +216,8 @@ static int snd_usb_create_stream(struct
 
 	if (! snd_usb_parse_audio_interface(chip, interface)) {
 		usb_set_interface(dev, interface, 0); /* reset the current interface */
-		usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
+		return usb_driver_claim_interface(&usb_audio_driver, iface,
+						  USB_AUDIO_IFACE_UNUSED);
 	}
 
 	return 0;
@@ -747,7 +747,7 @@ static void usb_audio_disconnect(struct
 	struct snd_card *card;
 	struct list_head *p;
 
-	if (chip == (void *)-1L)
+	if (chip == USB_AUDIO_IFACE_UNUSED)
 		return;
 
 	card = chip->card;
@@ -865,7 +865,7 @@ static int usb_audio_suspend(struct usb_
 	struct usb_mixer_interface *mixer;
 	struct list_head *p;
 
-	if (chip == (void *)-1L)
+	if (chip == USB_AUDIO_IFACE_UNUSED)
 		return 0;
 
 	if (!chip->num_suspended_intf++) {
@@ -897,7 +897,7 @@ static int __usb_audio_resume(struct usb
 	struct list_head *p;
 	int err = 0;
 
-	if (chip == (void *)-1L)
+	if (chip == USB_AUDIO_IFACE_UNUSED)
 		return 0;
 
 	atomic_inc(&chip->active); /* avoid autopm */
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -67,8 +67,12 @@ static int create_composite_quirk(struct
 		if (!iface)
 			continue;
 		if (quirk->ifnum != probed_ifnum &&
-		    !usb_interface_claimed(iface))
-			usb_driver_claim_interface(driver, iface, (void *)-1L);
+		    !usb_interface_claimed(iface)) {
+			err = usb_driver_claim_interface(driver, iface,
+							 USB_AUDIO_IFACE_UNUSED);
+			if (err < 0)
+				return err;
+		}
 	}
 
 	return 0;
@@ -403,8 +407,12 @@ static int create_autodetect_quirks(stru
 			continue;
 
 		err = create_autodetect_quirk(chip, iface, driver);
-		if (err >= 0)
-			usb_driver_claim_interface(driver, iface, (void *)-1L);
+		if (err >= 0) {
+			err = usb_driver_claim_interface(driver, iface,
+							 USB_AUDIO_IFACE_UNUSED);
+			if (err < 0)
+				return err;
+		}
 	}
 
 	return 0;
--- a/sound/usb/usbaudio.h
+++ b/sound/usb/usbaudio.h
@@ -70,6 +70,8 @@ struct snd_usb_audio {
 	struct usb_host_interface *ctrl_intf;	/* the audio control interface */
 };
 
+#define USB_AUDIO_IFACE_UNUSED	((void *)-1L)
+
 #define usb_audio_err(chip, fmt, args...) \
 	dev_err(&(chip)->dev->dev, fmt, ##args)
 #define usb_audio_warn(chip, fmt, args...) \