linux/sound/core/rawmidi_compat.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *   32bit -> 64bit ioctl wrapper for raw MIDI API
   4 *   Copyright (c) by Takashi Iwai <tiwai@suse.de>
   5 */
   6
   7/* This file included from rawmidi.c */
   8
   9#include <linux/compat.h>
  10
  11struct snd_rawmidi_params32 {
  12        s32 stream;
  13        u32 buffer_size;
  14        u32 avail_min;
  15        unsigned int no_active_sensing; /* avoid bit-field */
  16        unsigned int mode;
  17        unsigned char reserved[12];
  18} __attribute__((packed));
  19
  20static int snd_rawmidi_ioctl_params_compat(struct snd_rawmidi_file *rfile,
  21                                           struct snd_rawmidi_params32 __user *src)
  22{
  23        struct snd_rawmidi_params params;
  24        unsigned int val;
  25
  26        if (get_user(params.stream, &src->stream) ||
  27            get_user(params.buffer_size, &src->buffer_size) ||
  28            get_user(params.avail_min, &src->avail_min) ||
  29            get_user(params.mode, &src->mode) ||
  30            get_user(val, &src->no_active_sensing))
  31                return -EFAULT;
  32        params.no_active_sensing = val;
  33        switch (params.stream) {
  34        case SNDRV_RAWMIDI_STREAM_OUTPUT:
  35                if (!rfile->output)
  36                        return -EINVAL;
  37                return snd_rawmidi_output_params(rfile->output, &params);
  38        case SNDRV_RAWMIDI_STREAM_INPUT:
  39                if (!rfile->input)
  40                        return -EINVAL;
  41                return snd_rawmidi_input_params(rfile->input, &params);
  42        }
  43        return -EINVAL;
  44}
  45
  46struct compat_snd_rawmidi_status64 {
  47        s32 stream;
  48        u8 rsvd[4]; /* alignment */
  49        s64 tstamp_sec;
  50        s64 tstamp_nsec;
  51        u32 avail;
  52        u32 xruns;
  53        unsigned char reserved[16];
  54} __attribute__((packed));
  55
  56static int snd_rawmidi_ioctl_status_compat64(struct snd_rawmidi_file *rfile,
  57                                             struct compat_snd_rawmidi_status64 __user *src)
  58{
  59        int err;
  60        struct snd_rawmidi_status64 status;
  61        struct compat_snd_rawmidi_status64 compat_status;
  62
  63        if (get_user(status.stream, &src->stream))
  64                return -EFAULT;
  65
  66        switch (status.stream) {
  67        case SNDRV_RAWMIDI_STREAM_OUTPUT:
  68                if (!rfile->output)
  69                        return -EINVAL;
  70                err = snd_rawmidi_output_status(rfile->output, &status);
  71                break;
  72        case SNDRV_RAWMIDI_STREAM_INPUT:
  73                if (!rfile->input)
  74                        return -EINVAL;
  75                err = snd_rawmidi_input_status(rfile->input, &status);
  76                break;
  77        default:
  78                return -EINVAL;
  79        }
  80        if (err < 0)
  81                return err;
  82
  83        compat_status = (struct compat_snd_rawmidi_status64) {
  84                .stream = status.stream,
  85                .tstamp_sec = status.tstamp_sec,
  86                .tstamp_nsec = status.tstamp_nsec,
  87                .avail = status.avail,
  88                .xruns = status.xruns,
  89        };
  90
  91        if (copy_to_user(src, &compat_status, sizeof(*src)))
  92                return -EFAULT;
  93
  94        return 0;
  95}
  96
  97enum {
  98        SNDRV_RAWMIDI_IOCTL_PARAMS32 = _IOWR('W', 0x10, struct snd_rawmidi_params32),
  99        SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT32 = _IOWR('W', 0x20, struct snd_rawmidi_status32),
 100        SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT64 = _IOWR('W', 0x20, struct compat_snd_rawmidi_status64),
 101};
 102
 103static long snd_rawmidi_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
 104{
 105        struct snd_rawmidi_file *rfile;
 106        void __user *argp = compat_ptr(arg);
 107
 108        rfile = file->private_data;
 109        switch (cmd) {
 110        case SNDRV_RAWMIDI_IOCTL_PVERSION:
 111        case SNDRV_RAWMIDI_IOCTL_INFO:
 112        case SNDRV_RAWMIDI_IOCTL_DROP:
 113        case SNDRV_RAWMIDI_IOCTL_DRAIN:
 114                return snd_rawmidi_ioctl(file, cmd, (unsigned long)argp);
 115        case SNDRV_RAWMIDI_IOCTL_PARAMS32:
 116                return snd_rawmidi_ioctl_params_compat(rfile, argp);
 117        case SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT32:
 118                return snd_rawmidi_ioctl_status32(rfile, argp);
 119        case SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT64:
 120                return snd_rawmidi_ioctl_status_compat64(rfile, argp);
 121        }
 122        return -ENOIOCTLCMD;
 123}
 124