linux/drivers/most/configfs.c
Azeem Shaikh 2af4aa3be5 staging: most: Replace all non-returning strlcpy with strscpy
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230523021640.2406585-1-azeemshaikh38@gmail.com
2023-06-01 07:07:37 -07:00

725 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* configfs.c - Implementation of configfs interface to the driver stack
*
* Copyright (C) 2013-2015 Microchip Technology Germany II GmbH & Co. KG
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/configfs.h>
#include <linux/most.h>
#define MAX_STRING_SIZE 80
struct mdev_link {
struct config_item item;
struct list_head list;
bool create_link;
bool destroy_link;
u16 num_buffers;
u16 buffer_size;
u16 subbuffer_size;
u16 packets_per_xact;
u16 dbr_size;
char datatype[MAX_STRING_SIZE];
char direction[MAX_STRING_SIZE];
char name[MAX_STRING_SIZE];
char device[MAX_STRING_SIZE];
char channel[MAX_STRING_SIZE];
char comp[MAX_STRING_SIZE];
char comp_params[MAX_STRING_SIZE];
};
static struct list_head mdev_link_list;
static int set_cfg_buffer_size(struct mdev_link *link)
{
return most_set_cfg_buffer_size(link->device, link->channel,
link->buffer_size);
}
static int set_cfg_subbuffer_size(struct mdev_link *link)
{
return most_set_cfg_subbuffer_size(link->device, link->channel,
link->subbuffer_size);
}
static int set_cfg_dbr_size(struct mdev_link *link)
{
return most_set_cfg_dbr_size(link->device, link->channel,
link->dbr_size);
}
static int set_cfg_num_buffers(struct mdev_link *link)
{
return most_set_cfg_num_buffers(link->device, link->channel,
link->num_buffers);
}
static int set_cfg_packets_xact(struct mdev_link *link)
{
return most_set_cfg_packets_xact(link->device, link->channel,
link->packets_per_xact);
}
static int set_cfg_direction(struct mdev_link *link)
{
return most_set_cfg_direction(link->device, link->channel,
link->direction);
}
static int set_cfg_datatype(struct mdev_link *link)
{
return most_set_cfg_datatype(link->device, link->channel,
link->datatype);
}
static int (*set_config_val[])(struct mdev_link *link) = {
set_cfg_buffer_size,
set_cfg_subbuffer_size,
set_cfg_dbr_size,
set_cfg_num_buffers,
set_cfg_packets_xact,
set_cfg_direction,
set_cfg_datatype,
};
static struct mdev_link *to_mdev_link(struct config_item *item)
{
return container_of(item, struct mdev_link, item);
}
static int set_config_and_add_link(struct mdev_link *mdev_link)
{
int i;
int ret;
for (i = 0; i < ARRAY_SIZE(set_config_val); i++) {
ret = set_config_val[i](mdev_link);
if (ret < 0 && ret != -ENODEV) {
pr_err("Config failed\n");
return ret;
}
}
return most_add_link(mdev_link->device, mdev_link->channel,
mdev_link->comp, mdev_link->name,
mdev_link->comp_params);
}
static ssize_t mdev_link_create_link_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
bool tmp;
int ret;
ret = kstrtobool(page, &tmp);
if (ret)
return ret;
if (!tmp)
return count;
ret = set_config_and_add_link(mdev_link);
if (ret && ret != -ENODEV)
return ret;
list_add_tail(&mdev_link->list, &mdev_link_list);
mdev_link->create_link = tmp;
mdev_link->destroy_link = false;
return count;
}
static ssize_t mdev_link_destroy_link_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
bool tmp;
int ret;
ret = kstrtobool(page, &tmp);
if (ret)
return ret;
if (!tmp)
return count;
ret = most_remove_link(mdev_link->device, mdev_link->channel,
mdev_link->comp);
if (ret)
return ret;
if (!list_empty(&mdev_link_list))
list_del(&mdev_link->list);
mdev_link->destroy_link = tmp;
return count;
}
static ssize_t mdev_link_direction_show(struct config_item *item, char *page)
{
return snprintf(page, PAGE_SIZE, "%s\n", to_mdev_link(item)->direction);
}
static ssize_t mdev_link_direction_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
if (!sysfs_streq(page, "dir_rx") && !sysfs_streq(page, "rx") &&
!sysfs_streq(page, "dir_tx") && !sysfs_streq(page, "tx"))
return -EINVAL;
strcpy(mdev_link->direction, page);
strim(mdev_link->direction);
return count;
}
static ssize_t mdev_link_datatype_show(struct config_item *item, char *page)
{
return snprintf(page, PAGE_SIZE, "%s\n", to_mdev_link(item)->datatype);
}
static ssize_t mdev_link_datatype_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
if (!sysfs_streq(page, "control") && !sysfs_streq(page, "async") &&
!sysfs_streq(page, "sync") && !sysfs_streq(page, "isoc") &&
!sysfs_streq(page, "isoc_avp"))
return -EINVAL;
strcpy(mdev_link->datatype, page);
strim(mdev_link->datatype);
return count;
}
static ssize_t mdev_link_device_show(struct config_item *item, char *page)
{
return snprintf(page, PAGE_SIZE, "%s\n", to_mdev_link(item)->device);
}
static ssize_t mdev_link_device_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
strscpy(mdev_link->device, page, sizeof(mdev_link->device));
strim(mdev_link->device);
return count;
}
static ssize_t mdev_link_channel_show(struct config_item *item, char *page)
{
return snprintf(page, PAGE_SIZE, "%s\n", to_mdev_link(item)->channel);
}
static ssize_t mdev_link_channel_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
strscpy(mdev_link->channel, page, sizeof(mdev_link->channel));
strim(mdev_link->channel);
return count;
}
static ssize_t mdev_link_comp_show(struct config_item *item, char *page)
{
return snprintf(page, PAGE_SIZE, "%s\n", to_mdev_link(item)->comp);
}
static ssize_t mdev_link_comp_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
strscpy(mdev_link->comp, page, sizeof(mdev_link->comp));
strim(mdev_link->comp);
return count;
}
static ssize_t mdev_link_comp_params_show(struct config_item *item, char *page)
{
return snprintf(page, PAGE_SIZE, "%s\n",
to_mdev_link(item)->comp_params);
}
static ssize_t mdev_link_comp_params_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
strscpy(mdev_link->comp_params, page, sizeof(mdev_link->comp_params));
strim(mdev_link->comp_params);
return count;
}
static ssize_t mdev_link_num_buffers_show(struct config_item *item, char *page)
{
return snprintf(page, PAGE_SIZE, "%d\n",
to_mdev_link(item)->num_buffers);
}
static ssize_t mdev_link_num_buffers_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
int ret;
ret = kstrtou16(page, 0, &mdev_link->num_buffers);
if (ret)
return ret;
return count;
}
static ssize_t mdev_link_buffer_size_show(struct config_item *item, char *page)
{
return snprintf(page, PAGE_SIZE, "%d\n",
to_mdev_link(item)->buffer_size);
}
static ssize_t mdev_link_buffer_size_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
int ret;
ret = kstrtou16(page, 0, &mdev_link->buffer_size);
if (ret)
return ret;
return count;
}
static ssize_t mdev_link_subbuffer_size_show(struct config_item *item,
char *page)
{
return snprintf(page, PAGE_SIZE, "%d\n",
to_mdev_link(item)->subbuffer_size);
}
static ssize_t mdev_link_subbuffer_size_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
int ret;
ret = kstrtou16(page, 0, &mdev_link->subbuffer_size);
if (ret)
return ret;
return count;
}
static ssize_t mdev_link_packets_per_xact_show(struct config_item *item,
char *page)
{
return snprintf(page, PAGE_SIZE, "%d\n",
to_mdev_link(item)->packets_per_xact);
}
static ssize_t mdev_link_packets_per_xact_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
int ret;
ret = kstrtou16(page, 0, &mdev_link->packets_per_xact);
if (ret)
return ret;
return count;
}
static ssize_t mdev_link_dbr_size_show(struct config_item *item, char *page)
{
return snprintf(page, PAGE_SIZE, "%d\n", to_mdev_link(item)->dbr_size);
}
static ssize_t mdev_link_dbr_size_store(struct config_item *item,
const char *page, size_t count)
{
struct mdev_link *mdev_link = to_mdev_link(item);
int ret;
ret = kstrtou16(page, 0, &mdev_link->dbr_size);
if (ret)
return ret;
return count;
}
CONFIGFS_ATTR_WO(mdev_link_, create_link);
CONFIGFS_ATTR_WO(mdev_link_, destroy_link);
CONFIGFS_ATTR(mdev_link_, device);
CONFIGFS_ATTR(mdev_link_, channel);
CONFIGFS_ATTR(mdev_link_, comp);
CONFIGFS_ATTR(mdev_link_, comp_params);
CONFIGFS_ATTR(mdev_link_, num_buffers);
CONFIGFS_ATTR(mdev_link_, buffer_size);
CONFIGFS_ATTR(mdev_link_, subbuffer_size);
CONFIGFS_ATTR(mdev_link_, packets_per_xact);
CONFIGFS_ATTR(mdev_link_, datatype);
CONFIGFS_ATTR(mdev_link_, direction);
CONFIGFS_ATTR(mdev_link_, dbr_size);
static struct configfs_attribute *mdev_link_attrs[] = {
&mdev_link_attr_create_link,
&mdev_link_attr_destroy_link,
&mdev_link_attr_device,
&mdev_link_attr_channel,
&mdev_link_attr_comp,
&mdev_link_attr_comp_params,
&mdev_link_attr_num_buffers,
&mdev_link_attr_buffer_size,
&mdev_link_attr_subbuffer_size,
&mdev_link_attr_packets_per_xact,
&mdev_link_attr_datatype,
&mdev_link_attr_direction,
&mdev_link_attr_dbr_size,
NULL,
};
static void mdev_link_release(struct config_item *item)
{
struct mdev_link *mdev_link = to_mdev_link(item);
int ret;
if (mdev_link->destroy_link)
goto free_item;
ret = most_remove_link(mdev_link->device, mdev_link->channel,
mdev_link->comp);
if (ret) {
pr_err("Removing link failed.\n");
goto free_item;
}
if (!list_empty(&mdev_link_list))
list_del(&mdev_link->list);
free_item:
kfree(to_mdev_link(item));
}
static struct configfs_item_operations mdev_link_item_ops = {
.release = mdev_link_release,
};
static const struct config_item_type mdev_link_type = {
.ct_item_ops = &mdev_link_item_ops,
.ct_attrs = mdev_link_attrs,
.ct_owner = THIS_MODULE,
};
struct most_common {
struct config_group group;
struct module *mod;
struct configfs_subsystem subsys;
};
static struct most_common *to_most_common(struct configfs_subsystem *subsys)
{
return container_of(subsys, struct most_common, subsys);
}
static struct config_item *most_common_make_item(struct config_group *group,
const char *name)
{
struct mdev_link *mdev_link;
struct most_common *mc = to_most_common(group->cg_subsys);
mdev_link = kzalloc(sizeof(*mdev_link), GFP_KERNEL);
if (!mdev_link)
return ERR_PTR(-ENOMEM);
if (!try_module_get(mc->mod)) {
kfree(mdev_link);
return ERR_PTR(-ENOLCK);
}
config_item_init_type_name(&mdev_link->item, name,
&mdev_link_type);
if (!strcmp(group->cg_item.ci_namebuf, "most_cdev"))
strcpy(mdev_link->comp, "cdev");
else if (!strcmp(group->cg_item.ci_namebuf, "most_net"))
strcpy(mdev_link->comp, "net");
else if (!strcmp(group->cg_item.ci_namebuf, "most_video"))
strcpy(mdev_link->comp, "video");
strcpy(mdev_link->name, name);
return &mdev_link->item;
}
static void most_common_release(struct config_item *item)
{
struct config_group *group = to_config_group(item);
kfree(to_most_common(group->cg_subsys));
}
static struct configfs_item_operations most_common_item_ops = {
.release = most_common_release,
};
static void most_common_disconnect(struct config_group *group,
struct config_item *item)
{
struct most_common *mc = to_most_common(group->cg_subsys);
module_put(mc->mod);
}
static struct configfs_group_operations most_common_group_ops = {
.make_item = most_common_make_item,
.disconnect_notify = most_common_disconnect,
};
static const struct config_item_type most_common_type = {
.ct_item_ops = &most_common_item_ops,
.ct_group_ops = &most_common_group_ops,
.ct_owner = THIS_MODULE,
};
static struct most_common most_cdev = {
.subsys = {
.su_group = {
.cg_item = {
.ci_namebuf = "most_cdev",
.ci_type = &most_common_type,
},
},
},
};
static struct most_common most_net = {
.subsys = {
.su_group = {
.cg_item = {
.ci_namebuf = "most_net",
.ci_type = &most_common_type,
},
},
},
};
static struct most_common most_video = {
.subsys = {
.su_group = {
.cg_item = {
.ci_namebuf = "most_video",
.ci_type = &most_common_type,
},
},
},
};
struct most_snd_grp {
struct config_group group;
bool create_card;
struct list_head list;
};
static struct most_snd_grp *to_most_snd_grp(struct config_item *item)
{
return container_of(to_config_group(item), struct most_snd_grp, group);
}
static struct config_item *most_snd_grp_make_item(struct config_group *group,
const char *name)
{
struct mdev_link *mdev_link;
mdev_link = kzalloc(sizeof(*mdev_link), GFP_KERNEL);
if (!mdev_link)
return ERR_PTR(-ENOMEM);
config_item_init_type_name(&mdev_link->item, name, &mdev_link_type);
mdev_link->create_link = false;
strcpy(mdev_link->name, name);
strcpy(mdev_link->comp, "sound");
return &mdev_link->item;
}
static ssize_t most_snd_grp_create_card_store(struct config_item *item,
const char *page, size_t count)
{
struct most_snd_grp *snd_grp = to_most_snd_grp(item);
int ret;
bool tmp;
ret = kstrtobool(page, &tmp);
if (ret)
return ret;
if (tmp) {
ret = most_cfg_complete("sound");
if (ret)
return ret;
}
snd_grp->create_card = tmp;
return count;
}
CONFIGFS_ATTR_WO(most_snd_grp_, create_card);
static struct configfs_attribute *most_snd_grp_attrs[] = {
&most_snd_grp_attr_create_card,
NULL,
};
static void most_snd_grp_release(struct config_item *item)
{
struct most_snd_grp *group = to_most_snd_grp(item);
list_del(&group->list);
kfree(group);
}
static struct configfs_item_operations most_snd_grp_item_ops = {
.release = most_snd_grp_release,
};
static struct configfs_group_operations most_snd_grp_group_ops = {
.make_item = most_snd_grp_make_item,
};
static const struct config_item_type most_snd_grp_type = {
.ct_item_ops = &most_snd_grp_item_ops,
.ct_group_ops = &most_snd_grp_group_ops,
.ct_attrs = most_snd_grp_attrs,
.ct_owner = THIS_MODULE,
};
struct most_sound {
struct configfs_subsystem subsys;
struct list_head soundcard_list;
struct module *mod;
};
static struct config_group *most_sound_make_group(struct config_group *group,
const char *name)
{
struct most_snd_grp *most;
struct most_sound *ms = container_of(group->cg_subsys,
struct most_sound, subsys);
list_for_each_entry(most, &ms->soundcard_list, list) {
if (!most->create_card) {
pr_info("adapter configuration still in progress.\n");
return ERR_PTR(-EPROTO);
}
}
if (!try_module_get(ms->mod))
return ERR_PTR(-ENOLCK);
most = kzalloc(sizeof(*most), GFP_KERNEL);
if (!most) {
module_put(ms->mod);
return ERR_PTR(-ENOMEM);
}
config_group_init_type_name(&most->group, name, &most_snd_grp_type);
list_add_tail(&most->list, &ms->soundcard_list);
return &most->group;
}
static void most_sound_disconnect(struct config_group *group,
struct config_item *item)
{
struct most_sound *ms = container_of(group->cg_subsys,
struct most_sound, subsys);
module_put(ms->mod);
}
static struct configfs_group_operations most_sound_group_ops = {
.make_group = most_sound_make_group,
.disconnect_notify = most_sound_disconnect,
};
static const struct config_item_type most_sound_type = {
.ct_group_ops = &most_sound_group_ops,
.ct_owner = THIS_MODULE,
};
static struct most_sound most_sound_subsys = {
.subsys = {
.su_group = {
.cg_item = {
.ci_namebuf = "most_sound",
.ci_type = &most_sound_type,
},
},
},
};
int most_register_configfs_subsys(struct most_component *c)
{
int ret;
if (!strcmp(c->name, "cdev")) {
most_cdev.mod = c->mod;
ret = configfs_register_subsystem(&most_cdev.subsys);
} else if (!strcmp(c->name, "net")) {
most_net.mod = c->mod;
ret = configfs_register_subsystem(&most_net.subsys);
} else if (!strcmp(c->name, "video")) {
most_video.mod = c->mod;
ret = configfs_register_subsystem(&most_video.subsys);
} else if (!strcmp(c->name, "sound")) {
most_sound_subsys.mod = c->mod;
ret = configfs_register_subsystem(&most_sound_subsys.subsys);
} else {
return -ENODEV;
}
if (ret) {
pr_err("Error %d while registering subsystem %s\n",
ret, c->name);
}
return ret;
}
EXPORT_SYMBOL_GPL(most_register_configfs_subsys);
void most_interface_register_notify(const char *mdev)
{
bool register_snd_card = false;
struct mdev_link *mdev_link;
list_for_each_entry(mdev_link, &mdev_link_list, list) {
if (!strcmp(mdev_link->device, mdev)) {
set_config_and_add_link(mdev_link);
if (!strcmp(mdev_link->comp, "sound"))
register_snd_card = true;
}
}
if (register_snd_card)
most_cfg_complete("sound");
}
void most_deregister_configfs_subsys(struct most_component *c)
{
if (!strcmp(c->name, "cdev"))
configfs_unregister_subsystem(&most_cdev.subsys);
else if (!strcmp(c->name, "net"))
configfs_unregister_subsystem(&most_net.subsys);
else if (!strcmp(c->name, "video"))
configfs_unregister_subsystem(&most_video.subsys);
else if (!strcmp(c->name, "sound"))
configfs_unregister_subsystem(&most_sound_subsys.subsys);
}
EXPORT_SYMBOL_GPL(most_deregister_configfs_subsys);
int __init configfs_init(void)
{
config_group_init(&most_cdev.subsys.su_group);
mutex_init(&most_cdev.subsys.su_mutex);
config_group_init(&most_net.subsys.su_group);
mutex_init(&most_net.subsys.su_mutex);
config_group_init(&most_video.subsys.su_group);
mutex_init(&most_video.subsys.su_mutex);
config_group_init(&most_sound_subsys.subsys.su_group);
mutex_init(&most_sound_subsys.subsys.su_mutex);
INIT_LIST_HEAD(&most_sound_subsys.soundcard_list);
INIT_LIST_HEAD(&mdev_link_list);
return 0;
}