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 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(-)

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 ae667cf77e61..63f27ce64bcb 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...) \