remarkable-linux/sound/core/timer_compat.c
Takashi Iwai 3d4e8303f2 ALSA: timer: Remove kernel warning at compat ioctl error paths
Some timer compat ioctls have NULL checks of timer instance with
snd_BUG_ON() that bring up WARN_ON() when the debug option is set.
Actually the condition can be met in the normal situation and it's
confusing and bad to spew kernel warnings with stack trace there.
Let's remove snd_BUG_ON() invocation and replace with the simple
checks.  Also, correct the error code to EBADFD to follow the native
ioctl error handling.

Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-11-21 16:36:11 +01:00

183 lines
5.2 KiB
C

/*
* 32bit -> 64bit ioctl wrapper for timer API
* Copyright (c) by Takashi Iwai <tiwai@suse.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
/* This file included from timer.c */
#include <linux/compat.h>
/*
* ILP32/LP64 has different size for 'long' type. Additionally, the size
* of storage alignment differs depending on architectures. Here, '__packed'
* qualifier is used so that the size of this structure is multiple of 4 and
* it fits to any architectures with 32 bit storage alignment.
*/
struct snd_timer_gparams32 {
struct snd_timer_id tid;
u32 period_num;
u32 period_den;
unsigned char reserved[32];
} __packed;
struct snd_timer_info32 {
u32 flags;
s32 card;
unsigned char id[64];
unsigned char name[80];
u32 reserved0;
u32 resolution;
unsigned char reserved[64];
};
static int snd_timer_user_gparams_compat(struct file *file,
struct snd_timer_gparams32 __user *user)
{
struct snd_timer_gparams gparams;
if (copy_from_user(&gparams.tid, &user->tid, sizeof(gparams.tid)) ||
get_user(gparams.period_num, &user->period_num) ||
get_user(gparams.period_den, &user->period_den))
return -EFAULT;
return timer_set_gparams(&gparams);
}
static int snd_timer_user_info_compat(struct file *file,
struct snd_timer_info32 __user *_info)
{
struct snd_timer_user *tu;
struct snd_timer_info32 info;
struct snd_timer *t;
tu = file->private_data;
if (!tu->timeri)
return -EBADFD;
t = tu->timeri->timer;
if (!t)
return -EBADFD;
memset(&info, 0, sizeof(info));
info.card = t->card ? t->card->number : -1;
if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
info.flags |= SNDRV_TIMER_FLG_SLAVE;
strlcpy(info.id, t->id, sizeof(info.id));
strlcpy(info.name, t->name, sizeof(info.name));
info.resolution = t->hw.resolution;
if (copy_to_user(_info, &info, sizeof(*_info)))
return -EFAULT;
return 0;
}
struct snd_timer_status32 {
struct compat_timespec tstamp;
u32 resolution;
u32 lost;
u32 overrun;
u32 queue;
unsigned char reserved[64];
};
static int snd_timer_user_status_compat(struct file *file,
struct snd_timer_status32 __user *_status)
{
struct snd_timer_user *tu;
struct snd_timer_status32 status;
tu = file->private_data;
if (!tu->timeri)
return -EBADFD;
memset(&status, 0, sizeof(status));
status.tstamp.tv_sec = tu->tstamp.tv_sec;
status.tstamp.tv_nsec = tu->tstamp.tv_nsec;
status.resolution = snd_timer_resolution(tu->timeri);
status.lost = tu->timeri->lost;
status.overrun = tu->overrun;
spin_lock_irq(&tu->qlock);
status.queue = tu->qused;
spin_unlock_irq(&tu->qlock);
if (copy_to_user(_status, &status, sizeof(status)))
return -EFAULT;
return 0;
}
#ifdef CONFIG_X86_X32
/* X32 ABI has the same struct as x86-64 */
#define snd_timer_user_status_x32(file, s) \
snd_timer_user_status(file, s)
#endif /* CONFIG_X86_X32 */
/*
*/
enum {
SNDRV_TIMER_IOCTL_GPARAMS32 = _IOW('T', 0x04, struct snd_timer_gparams32),
SNDRV_TIMER_IOCTL_INFO32 = _IOR('T', 0x11, struct snd_timer_info32),
SNDRV_TIMER_IOCTL_STATUS32 = _IOW('T', 0x14, struct snd_timer_status32),
#ifdef CONFIG_X86_X32
SNDRV_TIMER_IOCTL_STATUS_X32 = _IOW('T', 0x14, struct snd_timer_status),
#endif /* CONFIG_X86_X32 */
};
static long __snd_timer_user_ioctl_compat(struct file *file, unsigned int cmd,
unsigned long arg)
{
void __user *argp = compat_ptr(arg);
switch (cmd) {
case SNDRV_TIMER_IOCTL_PVERSION:
case SNDRV_TIMER_IOCTL_TREAD:
case SNDRV_TIMER_IOCTL_GINFO:
case SNDRV_TIMER_IOCTL_GSTATUS:
case SNDRV_TIMER_IOCTL_SELECT:
case SNDRV_TIMER_IOCTL_PARAMS:
case SNDRV_TIMER_IOCTL_START:
case SNDRV_TIMER_IOCTL_START_OLD:
case SNDRV_TIMER_IOCTL_STOP:
case SNDRV_TIMER_IOCTL_STOP_OLD:
case SNDRV_TIMER_IOCTL_CONTINUE:
case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
case SNDRV_TIMER_IOCTL_PAUSE:
case SNDRV_TIMER_IOCTL_PAUSE_OLD:
case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
return __snd_timer_user_ioctl(file, cmd, (unsigned long)argp);
case SNDRV_TIMER_IOCTL_GPARAMS32:
return snd_timer_user_gparams_compat(file, argp);
case SNDRV_TIMER_IOCTL_INFO32:
return snd_timer_user_info_compat(file, argp);
case SNDRV_TIMER_IOCTL_STATUS32:
return snd_timer_user_status_compat(file, argp);
#ifdef CONFIG_X86_X32
case SNDRV_TIMER_IOCTL_STATUS_X32:
return snd_timer_user_status_x32(file, argp);
#endif /* CONFIG_X86_X32 */
}
return -ENOIOCTLCMD;
}
static long snd_timer_user_ioctl_compat(struct file *file, unsigned int cmd,
unsigned long arg)
{
struct snd_timer_user *tu = file->private_data;
long ret;
mutex_lock(&tu->ioctl_lock);
ret = __snd_timer_user_ioctl_compat(file, cmd, arg);
mutex_unlock(&tu->ioctl_lock);
return ret;
}