From 155b01b6baa54461a6e073cf037c263efdfa6878 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Beno=C3=AEt=20Sevens?= Date: Wed, 20 Nov 2024 12:41:44 +0000 Subject: [PATCH] ALSA: usb-audio: Fix potential out-of-bound accesses for Extigy and Mbox devices MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit b909df18ce2a998afef81d58bbd1a05dc0788c40 upstream. A bogus device can provide a bNumConfigurations value that exceeds the initial value used in usb_get_configuration for allocating dev->config. This can lead to out-of-bounds accesses later, e.g. in usb_destroy_configuration. Signed-off-by: Benoît Sevens Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@kernel.org Link: https://patch.msgid.link/20241120124144.3814457-1-bsevens@google.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/quirks.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c index 1b226c77c..fadc0aae4 100755 --- a/sound/usb/quirks.c +++ b/sound/usb/quirks.c @@ -595,6 +595,7 @@ int snd_usb_create_quirk(struct snd_usb_audio *chip, static int snd_usb_extigy_boot_quirk(struct usb_device *dev, struct usb_interface *intf) { struct usb_host_config *config = dev->actconfig; + struct usb_device_descriptor new_device_descriptor; int err; if (le16_to_cpu(get_cfg_desc(config)->wTotalLength) == EXTIGY_FIRMWARE_SIZE_OLD || @@ -606,10 +607,14 @@ static int snd_usb_extigy_boot_quirk(struct usb_device *dev, struct usb_interfac if (err < 0) dev_dbg(&dev->dev, "error sending boot message: %d\n", err); err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, - &dev->descriptor, sizeof(dev->descriptor)); - config = dev->actconfig; + &new_device_descriptor, sizeof(new_device_descriptor)); if (err < 0) dev_dbg(&dev->dev, "error usb_get_descriptor: %d\n", err); + if (new_device_descriptor.bNumConfigurations > dev->descriptor.bNumConfigurations) + dev_dbg(&dev->dev, "error too large bNumConfigurations: %d\n", + new_device_descriptor.bNumConfigurations); + else + memcpy(&dev->descriptor, &new_device_descriptor, sizeof(dev->descriptor)); err = usb_reset_configuration(dev); if (err < 0) dev_dbg(&dev->dev, "error usb_reset_configuration: %d\n", err); @@ -941,6 +946,7 @@ static void mbox2_setup_48_24_magic(struct usb_device *dev) static int snd_usb_mbox2_boot_quirk(struct usb_device *dev) { struct usb_host_config *config = dev->actconfig; + struct usb_device_descriptor new_device_descriptor; int err; u8 bootresponse[0x12]; int fwsize; @@ -976,10 +982,14 @@ static int snd_usb_mbox2_boot_quirk(struct usb_device *dev) dev_dbg(&dev->dev, "device initialised!\n"); err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, - &dev->descriptor, sizeof(dev->descriptor)); - config = dev->actconfig; + &new_device_descriptor, sizeof(new_device_descriptor)); if (err < 0) dev_dbg(&dev->dev, "error usb_get_descriptor: %d\n", err); + if (new_device_descriptor.bNumConfigurations > dev->descriptor.bNumConfigurations) + dev_dbg(&dev->dev, "error too large bNumConfigurations: %d\n", + new_device_descriptor.bNumConfigurations); + else + memcpy(&dev->descriptor, &new_device_descriptor, sizeof(dev->descriptor)); err = usb_reset_configuration(dev); if (err < 0) @@ -1024,7 +1034,6 @@ static int snd_usb_axefx3_boot_quirk(struct usb_device *dev) return 0; } - #define MICROBOOK_BUF_SIZE 128 static int snd_usb_motu_microbookii_communicate(struct usb_device *dev, u8 *buf,