[PATCH 5.12 497/677] ALSA: usb-audio: Add error checks for usb_driver_claim_interface() calls

From: Greg Kroah-Hartman
Date: Wed May 12 2021 - 15:03:50 EST


From: Takashi Iwai <tiwai@xxxxxxx>

[ Upstream commit 5fb45414ae03421255593fd5556aa2d1d82303aa ]

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@xxxxxxxxxxxx>
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@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/usb/card.c | 14 +++++++-------
sound/usb/quirks.c | 16 ++++++++++++----
sound/usb/usbaudio.h | 2 ++
3 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/sound/usb/card.c b/sound/usb/card.c
index 0826a437f8fc..7b7526d3a56e 100644
--- a/sound/usb/card.c
+++ b/sound/usb/card.c
@@ -181,9 +181,8 @@ static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int int
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 &&
@@ -203,7 +202,8 @@ static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int int

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;
@@ -862,7 +862,7 @@ static void usb_audio_disconnect(struct usb_interface *intf)
struct snd_card *card;
struct list_head *p;

- if (chip == (void *)-1L)
+ if (chip == USB_AUDIO_IFACE_UNUSED)
return;

card = chip->card;
@@ -992,7 +992,7 @@ static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
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++) {
@@ -1022,7 +1022,7 @@ static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume)
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 */
diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
index 176437a441e6..7c6e83eee71d 100644
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -55,8 +55,12 @@ static int create_composite_quirk(struct snd_usb_audio *chip,
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;
@@ -426,8 +430,12 @@ static int create_autodetect_quirks(struct snd_usb_audio *chip,
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;
diff --git a/sound/usb/usbaudio.h b/sound/usb/usbaudio.h
index 60b9dd7df6bb..8794c8658ab9 100644
--- a/sound/usb/usbaudio.h
+++ b/sound/usb/usbaudio.h
@@ -61,6 +61,8 @@ struct snd_usb_audio {
struct media_intf_devnode *ctl_intf_media_devnode;
};

+#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...) \
--
2.30.2