linux_dsm_epyc7002/include/sound/control.h
Takashi Iwai a91d66129f ALSA: hda - Fix incorrect TLV callback check introduced during set_fs() removal
The commit 99b5c5bb9a ("ALSA: hda - Remove the use of set_fs()")
converted the get_kctl_0dB_offset() call for killing set_fs() usage in
HD-audio codec code.  The conversion assumed that the TLV callback
used in HD-audio code is only snd_hda_mixer_amp() and applies the TLV
calculation locally.

Although this assumption is correct, and all slave kctls are actually
with that callback, the current code is still utterly buggy; it
doesn't hit this condition and falls back to the next check.  It's
because the function gets called after adding slave kctls to vmaster.
By assigning a slave kctl, the slave kctl object is faked inside
vmaster code, and the whole kctl ops are overridden.  Thus the
callback op points to a different value from what we've assumed.

More badly, as reported by the KERNEXEC and UDEREF features of PaX,
the code flow turns into the unexpected pitfall.  The next fallback
check is SNDRV_CTL_ELEM_ACCESS_TLV_READ access bit, and this always
hits for each kctl with TLV.  Then it evaluates the callback function
pointer wrongly as if it were a TLV array.  Although currently its
side-effect is fairly limited, this incorrect reference may lead to an
unpleasant result.

For addressing the regression, this patch introduces a new helper to
vmaster code, snd_ctl_apply_vmaster_slaves().  This works similarly
like the existing map_slaves() in hda_codec.c: it loops over the slave
list of the given master, and applies the given function to each
slave.  Then the initializer function receives the right kctl object
and we can compare the correct pointer instead of the faked one.

Also, for catching the similar breakage in future, give an error
message when the unexpected TLV callback is found and bail out
immediately.

Fixes: 99b5c5bb9a ("ALSA: hda - Remove the use of set_fs()")
Reported-by: PaX Team <pageexec@freemail.hu>
Cc: <stable@vger.kernel.org> # v4.13
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-10-18 12:27:00 +02:00

264 lines
8.6 KiB
C

#ifndef __SOUND_CONTROL_H
#define __SOUND_CONTROL_H
/*
* Header file for control interface
* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
*
*
* 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
*
*/
#include <linux/wait.h>
#include <sound/asound.h>
#define snd_kcontrol_chip(kcontrol) ((kcontrol)->private_data)
struct snd_kcontrol;
typedef int (snd_kcontrol_info_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_info * uinfo);
typedef int (snd_kcontrol_get_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
typedef int (snd_kcontrol_put_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
typedef int (snd_kcontrol_tlv_rw_t)(struct snd_kcontrol *kcontrol,
int op_flag, /* SNDRV_CTL_TLV_OP_XXX */
unsigned int size,
unsigned int __user *tlv);
enum {
SNDRV_CTL_TLV_OP_READ = 0,
SNDRV_CTL_TLV_OP_WRITE = 1,
SNDRV_CTL_TLV_OP_CMD = -1,
};
struct snd_kcontrol_new {
snd_ctl_elem_iface_t iface; /* interface identifier */
unsigned int device; /* device/client number */
unsigned int subdevice; /* subdevice (substream) number */
const unsigned char *name; /* ASCII name of item */
unsigned int index; /* index of item */
unsigned int access; /* access rights */
unsigned int count; /* count of same elements */
snd_kcontrol_info_t *info;
snd_kcontrol_get_t *get;
snd_kcontrol_put_t *put;
union {
snd_kcontrol_tlv_rw_t *c;
const unsigned int *p;
} tlv;
unsigned long private_value;
};
struct snd_kcontrol_volatile {
struct snd_ctl_file *owner; /* locked */
unsigned int access; /* access rights */
};
struct snd_kcontrol {
struct list_head list; /* list of controls */
struct snd_ctl_elem_id id;
unsigned int count; /* count of same elements */
snd_kcontrol_info_t *info;
snd_kcontrol_get_t *get;
snd_kcontrol_put_t *put;
union {
snd_kcontrol_tlv_rw_t *c;
const unsigned int *p;
} tlv;
unsigned long private_value;
void *private_data;
void (*private_free)(struct snd_kcontrol *kcontrol);
struct snd_kcontrol_volatile vd[0]; /* volatile data */
};
#define snd_kcontrol(n) list_entry(n, struct snd_kcontrol, list)
struct snd_kctl_event {
struct list_head list; /* list of events */
struct snd_ctl_elem_id id;
unsigned int mask;
};
#define snd_kctl_event(n) list_entry(n, struct snd_kctl_event, list)
struct pid;
enum {
SND_CTL_SUBDEV_PCM,
SND_CTL_SUBDEV_RAWMIDI,
SND_CTL_SUBDEV_ITEMS,
};
struct snd_ctl_file {
struct list_head list; /* list of all control files */
struct snd_card *card;
struct pid *pid;
int preferred_subdevice[SND_CTL_SUBDEV_ITEMS];
wait_queue_head_t change_sleep;
spinlock_t read_lock;
struct fasync_struct *fasync;
int subscribed; /* read interface is activated */
struct list_head events; /* waiting events for read */
};
#define snd_ctl_file(n) list_entry(n, struct snd_ctl_file, list)
typedef int (*snd_kctl_ioctl_func_t) (struct snd_card * card,
struct snd_ctl_file * control,
unsigned int cmd, unsigned long arg);
void snd_ctl_notify(struct snd_card * card, unsigned int mask, struct snd_ctl_elem_id * id);
struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, void * private_data);
void snd_ctl_free_one(struct snd_kcontrol * kcontrol);
int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol);
int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol);
int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, bool add_on_replace);
int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id);
int snd_ctl_rename_id(struct snd_card * card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id);
int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
int active);
struct snd_kcontrol *snd_ctl_find_numid(struct snd_card * card, unsigned int numid);
struct snd_kcontrol *snd_ctl_find_id(struct snd_card * card, struct snd_ctl_elem_id *id);
int snd_ctl_create(struct snd_card *card);
int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn);
int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn);
#ifdef CONFIG_COMPAT
int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn);
int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn);
#else
#define snd_ctl_register_ioctl_compat(fcn)
#define snd_ctl_unregister_ioctl_compat(fcn)
#endif
int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type);
static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
{
return id->numid - kctl->id.numid;
}
static inline unsigned int snd_ctl_get_ioffidx(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
{
return id->index - kctl->id.index;
}
static inline unsigned int snd_ctl_get_ioff(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
{
if (id->numid) {
return snd_ctl_get_ioffnum(kctl, id);
} else {
return snd_ctl_get_ioffidx(kctl, id);
}
}
static inline struct snd_ctl_elem_id *snd_ctl_build_ioff(struct snd_ctl_elem_id *dst_id,
struct snd_kcontrol *src_kctl,
unsigned int offset)
{
*dst_id = src_kctl->id;
dst_id->index += offset;
dst_id->numid += offset;
return dst_id;
}
/*
* Frequently used control callbacks/helpers
*/
int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_info *uinfo);
int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_info *uinfo);
int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
unsigned int items, const char *const names[]);
/*
* virtual master control
*/
struct snd_kcontrol *snd_ctl_make_virtual_master(char *name,
const unsigned int *tlv);
int _snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave,
unsigned int flags);
/* optional flags for slave */
#define SND_CTL_SLAVE_NEED_UPDATE (1 << 0)
/**
* snd_ctl_add_slave - Add a virtual slave control
* @master: vmaster element
* @slave: slave element to add
*
* Add a virtual slave control to the given master element created via
* snd_ctl_create_virtual_master() beforehand.
*
* All slaves must be the same type (returning the same information
* via info callback). The function doesn't check it, so it's your
* responsibility.
*
* Also, some additional limitations:
* at most two channels,
* logarithmic volume control (dB level) thus no linear volume,
* master can only attenuate the volume without gain
*
* Return: Zero if successful or a negative error code.
*/
static inline int
snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave)
{
return _snd_ctl_add_slave(master, slave, 0);
}
/**
* snd_ctl_add_slave_uncached - Add a virtual slave control
* @master: vmaster element
* @slave: slave element to add
*
* Add a virtual slave control to the given master.
* Unlike snd_ctl_add_slave(), the element added via this function
* is supposed to have volatile values, and get callback is called
* at each time queried from the master.
*
* When the control peeks the hardware values directly and the value
* can be changed by other means than the put callback of the element,
* this function should be used to keep the value always up-to-date.
*
* Return: Zero if successful or a negative error code.
*/
static inline int
snd_ctl_add_slave_uncached(struct snd_kcontrol *master,
struct snd_kcontrol *slave)
{
return _snd_ctl_add_slave(master, slave, SND_CTL_SLAVE_NEED_UPDATE);
}
int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kctl,
void (*hook)(void *private_data, int),
void *private_data);
void snd_ctl_sync_vmaster(struct snd_kcontrol *kctl, bool hook_only);
#define snd_ctl_sync_vmaster_hook(kctl) snd_ctl_sync_vmaster(kctl, true)
int snd_ctl_apply_vmaster_slaves(struct snd_kcontrol *kctl,
int (*func)(struct snd_kcontrol *, void *),
void *arg);
/*
* Helper functions for jack-detection controls
*/
struct snd_kcontrol *
snd_kctl_jack_new(const char *name, struct snd_card *card);
void snd_kctl_jack_report(struct snd_card *card,
struct snd_kcontrol *kctl, bool status);
#endif /* __SOUND_CONTROL_H */