linux/drivers/sbus/char/openprom.c
Sam Ravnborg 21916a4a29 openprom: fix warning
Fix following warnings:
openprom.c:510:2: warning: 'tmp' may be used uninitialized in this function [-Wmaybe-uninitialized]
openprom.c:503:3: warning: 'str' may be used uninitialized in this function [-Wmaybe-uninitialized]
openprom.c:459:8: warning: 'str' may be used uninitialized in this function [-Wmaybe-uninitialized]
openprom.c:422:7: warning: 'str' may be used uninitialized in this function [-Wmaybe-uninitialized]

Fixed by introducing PTR_ERR etc.
This simplified the code as a nice side effect.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-20 18:33:37 -07:00

748 lines
16 KiB
C

/*
* Linux/SPARC PROM Configuration Driver
* Copyright (C) 1996 Thomas K. Dyas (tdyas@noc.rutgers.edu)
* Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
*
* This character device driver allows user programs to access the
* PROM device tree. It is compatible with the SunOS /dev/openprom
* driver and the NetBSD /dev/openprom driver. The SunOS eeprom
* utility works without any modifications.
*
* The driver uses a minor number under the misc device major. The
* file read/write mode determines the type of access to the PROM.
* Interrupts are disabled whenever the driver calls into the PROM for
* sanity's sake.
*/
/* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/string.h>
#include <linux/miscdevice.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <asm/oplib.h>
#include <asm/prom.h>
#include <asm/uaccess.h>
#include <asm/openpromio.h>
#ifdef CONFIG_PCI
#include <linux/pci.h>
#endif
MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost (ecd@skynet.be)");
MODULE_DESCRIPTION("OPENPROM Configuration Driver");
MODULE_LICENSE("GPL");
MODULE_VERSION("1.0");
MODULE_ALIAS_MISCDEV(SUN_OPENPROM_MINOR);
/* Private data kept by the driver for each descriptor. */
typedef struct openprom_private_data
{
struct device_node *current_node; /* Current node for SunOS ioctls. */
struct device_node *lastnode; /* Last valid node used by BSD ioctls. */
} DATA;
/* ID of the PROM node containing all of the EEPROM options. */
static DEFINE_MUTEX(openprom_mutex);
static struct device_node *options_node;
/*
* Copy an openpromio structure into kernel space from user space.
* This routine does error checking to make sure that all memory
* accesses are within bounds. A pointer to the allocated openpromio
* structure will be placed in "*opp_p". Return value is the length
* of the user supplied buffer.
*/
static int copyin(struct openpromio __user *info, struct openpromio **opp_p)
{
unsigned int bufsize;
if (!info || !opp_p)
return -EFAULT;
if (get_user(bufsize, &info->oprom_size))
return -EFAULT;
if (bufsize == 0)
return -EINVAL;
/* If the bufsize is too large, just limit it.
* Fix from Jason Rappleye.
*/
if (bufsize > OPROMMAXPARAM)
bufsize = OPROMMAXPARAM;
if (!(*opp_p = kzalloc(sizeof(int) + bufsize + 1, GFP_KERNEL)))
return -ENOMEM;
if (copy_from_user(&(*opp_p)->oprom_array,
&info->oprom_array, bufsize)) {
kfree(*opp_p);
return -EFAULT;
}
return bufsize;
}
static int getstrings(struct openpromio __user *info, struct openpromio **opp_p)
{
int n, bufsize;
char c;
if (!info || !opp_p)
return -EFAULT;
if (!(*opp_p = kzalloc(sizeof(int) + OPROMMAXPARAM + 1, GFP_KERNEL)))
return -ENOMEM;
(*opp_p)->oprom_size = 0;
n = bufsize = 0;
while ((n < 2) && (bufsize < OPROMMAXPARAM)) {
if (get_user(c, &info->oprom_array[bufsize])) {
kfree(*opp_p);
return -EFAULT;
}
if (c == '\0')
n++;
(*opp_p)->oprom_array[bufsize++] = c;
}
if (!n) {
kfree(*opp_p);
return -EINVAL;
}
return bufsize;
}
/*
* Copy an openpromio structure in kernel space back to user space.
*/
static int copyout(void __user *info, struct openpromio *opp, int len)
{
if (copy_to_user(info, opp, len))
return -EFAULT;
return 0;
}
static int opromgetprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
{
const void *pval;
int len;
if (!dp ||
!(pval = of_get_property(dp, op->oprom_array, &len)) ||
len <= 0 || len > bufsize)
return copyout(argp, op, sizeof(int));
memcpy(op->oprom_array, pval, len);
op->oprom_array[len] = '\0';
op->oprom_size = len;
return copyout(argp, op, sizeof(int) + bufsize);
}
static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
{
struct property *prop;
int len;
if (!dp)
return copyout(argp, op, sizeof(int));
if (op->oprom_array[0] == '\0') {
prop = dp->properties;
if (!prop)
return copyout(argp, op, sizeof(int));
len = strlen(prop->name);
} else {
prop = of_find_property(dp, op->oprom_array, NULL);
if (!prop ||
!prop->next ||
(len = strlen(prop->next->name)) + 1 > bufsize)
return copyout(argp, op, sizeof(int));
prop = prop->next;
}
memcpy(op->oprom_array, prop->name, len);
op->oprom_array[len] = '\0';
op->oprom_size = ++len;
return copyout(argp, op, sizeof(int) + bufsize);
}
static int opromsetopt(struct device_node *dp, struct openpromio *op, int bufsize)
{
char *buf = op->oprom_array + strlen(op->oprom_array) + 1;
int len = op->oprom_array + bufsize - buf;
return of_set_property(options_node, op->oprom_array, buf, len);
}
static int opromnext(void __user *argp, unsigned int cmd, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
{
phandle ph;
BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
if (bufsize < sizeof(phandle))
return -EINVAL;
ph = *((int *) op->oprom_array);
if (ph) {
dp = of_find_node_by_phandle(ph);
if (!dp)
return -EINVAL;
switch (cmd) {
case OPROMNEXT:
dp = dp->sibling;
break;
case OPROMCHILD:
dp = dp->child;
break;
case OPROMSETCUR:
default:
break;
}
} else {
/* Sibling of node zero is the root node. */
if (cmd != OPROMNEXT)
return -EINVAL;
dp = of_find_node_by_path("/");
}
ph = 0;
if (dp)
ph = dp->phandle;
data->current_node = dp;
*((int *) op->oprom_array) = ph;
op->oprom_size = sizeof(phandle);
return copyout(argp, op, bufsize + sizeof(int));
}
static int oprompci2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
{
int err = -EINVAL;
if (bufsize >= 2*sizeof(int)) {
#ifdef CONFIG_PCI
struct pci_dev *pdev;
struct device_node *dp;
pdev = pci_get_bus_and_slot (((int *) op->oprom_array)[0],
((int *) op->oprom_array)[1]);
dp = pci_device_to_OF_node(pdev);
data->current_node = dp;
*((int *)op->oprom_array) = dp->phandle;
op->oprom_size = sizeof(int);
err = copyout(argp, op, bufsize + sizeof(int));
pci_dev_put(pdev);
#endif
}
return err;
}
static int oprompath2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
{
phandle ph = 0;
dp = of_find_node_by_path(op->oprom_array);
if (dp)
ph = dp->phandle;
data->current_node = dp;
*((int *)op->oprom_array) = ph;
op->oprom_size = sizeof(int);
return copyout(argp, op, bufsize + sizeof(int));
}
static int opromgetbootargs(void __user *argp, struct openpromio *op, int bufsize)
{
char *buf = saved_command_line;
int len = strlen(buf);
if (len > bufsize)
return -EINVAL;
strcpy(op->oprom_array, buf);
op->oprom_size = len;
return copyout(argp, op, bufsize + sizeof(int));
}
/*
* SunOS and Solaris /dev/openprom ioctl calls.
*/
static long openprom_sunos_ioctl(struct file * file,
unsigned int cmd, unsigned long arg,
struct device_node *dp)
{
DATA *data = file->private_data;
struct openpromio *opp = NULL;
int bufsize, error = 0;
static int cnt;
void __user *argp = (void __user *)arg;
if (cmd == OPROMSETOPT)
bufsize = getstrings(argp, &opp);
else
bufsize = copyin(argp, &opp);
if (bufsize < 0)
return bufsize;
mutex_lock(&openprom_mutex);
switch (cmd) {
case OPROMGETOPT:
case OPROMGETPROP:
error = opromgetprop(argp, dp, opp, bufsize);
break;
case OPROMNXTOPT:
case OPROMNXTPROP:
error = opromnxtprop(argp, dp, opp, bufsize);
break;
case OPROMSETOPT:
case OPROMSETOPT2:
error = opromsetopt(dp, opp, bufsize);
break;
case OPROMNEXT:
case OPROMCHILD:
case OPROMSETCUR:
error = opromnext(argp, cmd, dp, opp, bufsize, data);
break;
case OPROMPCI2NODE:
error = oprompci2node(argp, dp, opp, bufsize, data);
break;
case OPROMPATH2NODE:
error = oprompath2node(argp, dp, opp, bufsize, data);
break;
case OPROMGETBOOTARGS:
error = opromgetbootargs(argp, opp, bufsize);
break;
case OPROMU2P:
case OPROMGETCONS:
case OPROMGETFBNAME:
if (cnt++ < 10)
printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n");
error = -EINVAL;
break;
default:
if (cnt++ < 10)
printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg);
error = -EINVAL;
break;
}
kfree(opp);
mutex_unlock(&openprom_mutex);
return error;
}
static struct device_node *get_node(phandle n, DATA *data)
{
struct device_node *dp = of_find_node_by_phandle(n);
if (dp)
data->lastnode = dp;
return dp;
}
/* Copy in a whole string from userspace into kernelspace. */
static char * copyin_string(char __user *user, size_t len)
{
if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0)
return ERR_PTR(-EINVAL);
return memdup_user_nul(user, len);
}
/*
* NetBSD /dev/openprom ioctl calls.
*/
static int opiocget(void __user *argp, DATA *data)
{
struct opiocdesc op;
struct device_node *dp;
char *str;
const void *pval;
int err, len;
if (copy_from_user(&op, argp, sizeof(op)))
return -EFAULT;
dp = get_node(op.op_nodeid, data);
str = copyin_string(op.op_name, op.op_namelen);
if (IS_ERR(str))
return PTR_ERR(str);
pval = of_get_property(dp, str, &len);
err = 0;
if (!pval || len > op.op_buflen) {
err = -EINVAL;
} else {
op.op_buflen = len;
if (copy_to_user(argp, &op, sizeof(op)) ||
copy_to_user(op.op_buf, pval, len))
err = -EFAULT;
}
kfree(str);
return err;
}
static int opiocnextprop(void __user *argp, DATA *data)
{
struct opiocdesc op;
struct device_node *dp;
struct property *prop;
char *str;
int len;
if (copy_from_user(&op, argp, sizeof(op)))
return -EFAULT;
dp = get_node(op.op_nodeid, data);
if (!dp)
return -EINVAL;
str = copyin_string(op.op_name, op.op_namelen);
if (IS_ERR(str))
return PTR_ERR(str);
if (str[0] == '\0') {
prop = dp->properties;
} else {
prop = of_find_property(dp, str, NULL);
if (prop)
prop = prop->next;
}
kfree(str);
if (!prop)
len = 0;
else
len = prop->length;
if (len > op.op_buflen)
len = op.op_buflen;
if (copy_to_user(argp, &op, sizeof(op)))
return -EFAULT;
if (len &&
copy_to_user(op.op_buf, prop->value, len))
return -EFAULT;
return 0;
}
static int opiocset(void __user *argp, DATA *data)
{
struct opiocdesc op;
struct device_node *dp;
char *str, *tmp;
int err;
if (copy_from_user(&op, argp, sizeof(op)))
return -EFAULT;
dp = get_node(op.op_nodeid, data);
if (!dp)
return -EINVAL;
str = copyin_string(op.op_name, op.op_namelen);
if (IS_ERR(str))
return PTR_ERR(str);
tmp = copyin_string(op.op_buf, op.op_buflen);
if (IS_ERR(tmp)) {
kfree(str);
return PTR_ERR(tmp);
}
err = of_set_property(dp, str, tmp, op.op_buflen);
kfree(str);
kfree(tmp);
return err;
}
static int opiocgetnext(unsigned int cmd, void __user *argp)
{
struct device_node *dp;
phandle nd;
BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
if (copy_from_user(&nd, argp, sizeof(phandle)))
return -EFAULT;
if (nd == 0) {
if (cmd != OPIOCGETNEXT)
return -EINVAL;
dp = of_find_node_by_path("/");
} else {
dp = of_find_node_by_phandle(nd);
nd = 0;
if (dp) {
if (cmd == OPIOCGETNEXT)
dp = dp->sibling;
else
dp = dp->child;
}
}
if (dp)
nd = dp->phandle;
if (copy_to_user(argp, &nd, sizeof(phandle)))
return -EFAULT;
return 0;
}
static int openprom_bsd_ioctl(struct file * file,
unsigned int cmd, unsigned long arg)
{
DATA *data = file->private_data;
void __user *argp = (void __user *)arg;
int err;
mutex_lock(&openprom_mutex);
switch (cmd) {
case OPIOCGET:
err = opiocget(argp, data);
break;
case OPIOCNEXTPROP:
err = opiocnextprop(argp, data);
break;
case OPIOCSET:
err = opiocset(argp, data);
break;
case OPIOCGETOPTNODE:
BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
err = 0;
if (copy_to_user(argp, &options_node->phandle, sizeof(phandle)))
err = -EFAULT;
break;
case OPIOCGETNEXT:
case OPIOCGETCHILD:
err = opiocgetnext(cmd, argp);
break;
default:
err = -EINVAL;
break;
}
mutex_unlock(&openprom_mutex);
return err;
}
/*
* Handoff control to the correct ioctl handler.
*/
static long openprom_ioctl(struct file * file,
unsigned int cmd, unsigned long arg)
{
DATA *data = file->private_data;
switch (cmd) {
case OPROMGETOPT:
case OPROMNXTOPT:
if ((file->f_mode & FMODE_READ) == 0)
return -EPERM;
return openprom_sunos_ioctl(file, cmd, arg,
options_node);
case OPROMSETOPT:
case OPROMSETOPT2:
if ((file->f_mode & FMODE_WRITE) == 0)
return -EPERM;
return openprom_sunos_ioctl(file, cmd, arg,
options_node);
case OPROMNEXT:
case OPROMCHILD:
case OPROMGETPROP:
case OPROMNXTPROP:
if ((file->f_mode & FMODE_READ) == 0)
return -EPERM;
return openprom_sunos_ioctl(file, cmd, arg,
data->current_node);
case OPROMU2P:
case OPROMGETCONS:
case OPROMGETFBNAME:
case OPROMGETBOOTARGS:
case OPROMSETCUR:
case OPROMPCI2NODE:
case OPROMPATH2NODE:
if ((file->f_mode & FMODE_READ) == 0)
return -EPERM;
return openprom_sunos_ioctl(file, cmd, arg, NULL);
case OPIOCGET:
case OPIOCNEXTPROP:
case OPIOCGETOPTNODE:
case OPIOCGETNEXT:
case OPIOCGETCHILD:
if ((file->f_mode & FMODE_READ) == 0)
return -EBADF;
return openprom_bsd_ioctl(file,cmd,arg);
case OPIOCSET:
if ((file->f_mode & FMODE_WRITE) == 0)
return -EBADF;
return openprom_bsd_ioctl(file,cmd,arg);
default:
return -EINVAL;
};
}
static long openprom_compat_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
long rval = -ENOTTY;
/*
* SunOS/Solaris only, the NetBSD one's have embedded pointers in
* the arg which we'd need to clean up...
*/
switch (cmd) {
case OPROMGETOPT:
case OPROMSETOPT:
case OPROMNXTOPT:
case OPROMSETOPT2:
case OPROMNEXT:
case OPROMCHILD:
case OPROMGETPROP:
case OPROMNXTPROP:
case OPROMU2P:
case OPROMGETCONS:
case OPROMGETFBNAME:
case OPROMGETBOOTARGS:
case OPROMSETCUR:
case OPROMPCI2NODE:
case OPROMPATH2NODE:
rval = openprom_ioctl(file, cmd, arg);
break;
}
return rval;
}
static int openprom_open(struct inode * inode, struct file * file)
{
DATA *data;
data = kmalloc(sizeof(DATA), GFP_KERNEL);
if (!data)
return -ENOMEM;
mutex_lock(&openprom_mutex);
data->current_node = of_find_node_by_path("/");
data->lastnode = data->current_node;
file->private_data = (void *) data;
mutex_unlock(&openprom_mutex);
return 0;
}
static int openprom_release(struct inode * inode, struct file * file)
{
kfree(file->private_data);
return 0;
}
static const struct file_operations openprom_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.unlocked_ioctl = openprom_ioctl,
.compat_ioctl = openprom_compat_ioctl,
.open = openprom_open,
.release = openprom_release,
};
static struct miscdevice openprom_dev = {
.minor = SUN_OPENPROM_MINOR,
.name = "openprom",
.fops = &openprom_fops,
};
static int __init openprom_init(void)
{
struct device_node *dp;
int err;
err = misc_register(&openprom_dev);
if (err)
return err;
dp = of_find_node_by_path("/");
dp = dp->child;
while (dp) {
if (!strcmp(dp->name, "options"))
break;
dp = dp->sibling;
}
options_node = dp;
if (!options_node) {
misc_deregister(&openprom_dev);
return -EIO;
}
return 0;
}
static void __exit openprom_cleanup(void)
{
misc_deregister(&openprom_dev);
}
module_init(openprom_init);
module_exit(openprom_cleanup);