linux/sound/usb/helper.h
Takashi Iwai 801ebf1043 ALSA: usb-audio: Sanity checks for each pipe and EP types
The recent USB core code performs sanity checks for the given pipe and
EP types, and it can be hit by manipulated USB descriptors by syzbot.
For making syzbot happier, this patch introduces a local helper for a
sanity check in the driver side and calls it at each place before the
message handling, so that we can avoid the WARNING splats.

Reported-by: syzbot+d952e5e28f5fb7718d23@syzkaller.appspotmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-06-24 15:11:06 +02:00

35 lines
1.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __USBAUDIO_HELPER_H
#define __USBAUDIO_HELPER_H
unsigned int snd_usb_combine_bytes(unsigned char *bytes, int size);
void *snd_usb_find_desc(void *descstart, int desclen, void *after, u8 dtype);
void *snd_usb_find_csint_desc(void *descstart, int desclen, void *after, u8 dsubtype);
int snd_usb_pipe_sanity_check(struct usb_device *dev, unsigned int pipe);
int snd_usb_ctl_msg(struct usb_device *dev, unsigned int pipe,
__u8 request, __u8 requesttype, __u16 value, __u16 index,
void *data, __u16 size);
unsigned char snd_usb_parse_datainterval(struct snd_usb_audio *chip,
struct usb_host_interface *alts);
/*
* retrieve usb_interface descriptor from the host interface
* (conditional for compatibility with the older API)
*/
#define get_iface_desc(iface) (&(iface)->desc)
#define get_endpoint(alt,ep) (&(alt)->endpoint[ep].desc)
#define get_ep_desc(ep) (&(ep)->desc)
#define get_cfg_desc(cfg) (&(cfg)->desc)
#define snd_usb_get_speed(dev) ((dev)->speed)
static inline int snd_usb_ctrl_intf(struct snd_usb_audio *chip)
{
return get_iface_desc(chip->ctrl_intf)->bInterfaceNumber;
}
#endif /* __USBAUDIO_HELPER_H */