kernel_optimize_test/sound/core/rawmidi_compat.c
Baolin Wang d9e5582c4b ALSA: Avoid using timespec for struct snd_rawmidi_status
The struct snd_rawmidi_status will use 'timespec' type variables to record
timestamp, which is not year 2038 safe on 32bits system.

Thus we introduced 'struct snd_rawmidi_status32' and 'struct snd_rawmidi_status64'
to handle 32bit time_t and 64bit time_t in native mode, which replace
timespec with s64 type.

In compat mode, we renamed or introduced new structures to handle 32bit/64bit
time_t in compatible mode. The 'struct snd_rawmidi_status32' and
snd_rawmidi_ioctl_status32() are used to handle 32bit time_t in compat mode.
'struct compat_snd_rawmidi_status64' is used to handle 64bit time_t.

When glibc changes time_t to 64-bit, any recompiled program will issue ioctl
commands that the kernel does not understand without this patch.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-12-11 22:06:16 +01:00

122 lines
3.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 32bit -> 64bit ioctl wrapper for raw MIDI API
* Copyright (c) by Takashi Iwai <tiwai@suse.de>
*/
/* This file included from rawmidi.c */
#include <linux/compat.h>
struct snd_rawmidi_params32 {
s32 stream;
u32 buffer_size;
u32 avail_min;
unsigned int no_active_sensing; /* avoid bit-field */
unsigned char reserved[16];
} __attribute__((packed));
static int snd_rawmidi_ioctl_params_compat(struct snd_rawmidi_file *rfile,
struct snd_rawmidi_params32 __user *src)
{
struct snd_rawmidi_params params;
unsigned int val;
if (get_user(params.stream, &src->stream) ||
get_user(params.buffer_size, &src->buffer_size) ||
get_user(params.avail_min, &src->avail_min) ||
get_user(val, &src->no_active_sensing))
return -EFAULT;
params.no_active_sensing = val;
switch (params.stream) {
case SNDRV_RAWMIDI_STREAM_OUTPUT:
if (!rfile->output)
return -EINVAL;
return snd_rawmidi_output_params(rfile->output, &params);
case SNDRV_RAWMIDI_STREAM_INPUT:
if (!rfile->input)
return -EINVAL;
return snd_rawmidi_input_params(rfile->input, &params);
}
return -EINVAL;
}
struct compat_snd_rawmidi_status64 {
s32 stream;
u8 rsvd[4]; /* alignment */
s64 tstamp_sec;
s64 tstamp_nsec;
u32 avail;
u32 xruns;
unsigned char reserved[16];
} __attribute__((packed));
static int snd_rawmidi_ioctl_status_compat64(struct snd_rawmidi_file *rfile,
struct compat_snd_rawmidi_status64 __user *src)
{
int err;
struct snd_rawmidi_status64 status;
struct compat_snd_rawmidi_status64 compat_status;
if (get_user(status.stream, &src->stream))
return -EFAULT;
switch (status.stream) {
case SNDRV_RAWMIDI_STREAM_OUTPUT:
if (!rfile->output)
return -EINVAL;
err = snd_rawmidi_output_status(rfile->output, &status);
break;
case SNDRV_RAWMIDI_STREAM_INPUT:
if (!rfile->input)
return -EINVAL;
err = snd_rawmidi_input_status(rfile->input, &status);
break;
default:
return -EINVAL;
}
if (err < 0)
return err;
compat_status = (struct compat_snd_rawmidi_status64) {
.stream = status.stream,
.tstamp_sec = status.tstamp_sec,
.tstamp_nsec = status.tstamp_nsec,
.avail = status.avail,
.xruns = status.xruns,
};
if (copy_to_user(src, &compat_status, sizeof(*src)))
return -EFAULT;
return 0;
}
enum {
SNDRV_RAWMIDI_IOCTL_PARAMS32 = _IOWR('W', 0x10, struct snd_rawmidi_params32),
SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT32 = _IOWR('W', 0x20, struct snd_rawmidi_status32),
SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT64 = _IOWR('W', 0x20, struct compat_snd_rawmidi_status64),
};
static long snd_rawmidi_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
{
struct snd_rawmidi_file *rfile;
void __user *argp = compat_ptr(arg);
rfile = file->private_data;
switch (cmd) {
case SNDRV_RAWMIDI_IOCTL_PVERSION:
case SNDRV_RAWMIDI_IOCTL_INFO:
case SNDRV_RAWMIDI_IOCTL_DROP:
case SNDRV_RAWMIDI_IOCTL_DRAIN:
return snd_rawmidi_ioctl(file, cmd, (unsigned long)argp);
case SNDRV_RAWMIDI_IOCTL_PARAMS32:
return snd_rawmidi_ioctl_params_compat(rfile, argp);
case SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT32:
return snd_rawmidi_ioctl_status32(rfile, argp);
case SNDRV_RAWMIDI_IOCTL_STATUS_COMPAT64:
return snd_rawmidi_ioctl_status_compat64(rfile, argp);
}
return -ENOIOCTLCMD;
}