This is a note to let you know that I've just added the patch titled ALSA: usb-audio: Add error checks for usb_driver_claim_interface() calls to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: alsa-usb-audio-add-error-checks-for-usb_driver_claim.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e259d9676b8d3a6eb3db9fa2aa6f34a2d6737937 Author: Takashi Iwai <tiwai@xxxxxxx> Date: Tue Apr 6 13:35:34 2021 +0200 ALSA: usb-audio: Add error checks for usb_driver_claim_interface() calls [ 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> diff --git a/sound/usb/card.c b/sound/usb/card.c index 61d303f4283d..3ded5fe94cea 100644 --- a/sound/usb/card.c +++ b/sound/usb/card.c @@ -179,9 +179,8 @@ 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 && @@ -201,7 +200,8 @@ 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; @@ -610,7 +610,7 @@ 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; @@ -710,7 +710,7 @@ 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++) { @@ -740,7 +740,7 @@ 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 cd615514a5ff..7979a9e19c53 100644 --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -66,8 +66,12 @@ 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; @@ -399,8 +403,12 @@ 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 c5338be3aa37..09ecc7afdc4f 100644 --- a/sound/usb/usbaudio.h +++ b/sound/usb/usbaudio.h @@ -62,6 +62,8 @@ 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...) \