kernel_optimize_test/drivers/pnp/pnpbios/proc.c
Jesper Juhl a8b0ac0873 pnp: avoid a small unlikely memory leak in proc_read_escd()
There's a small and unlikely memory leak in
drivers/pnp/pnpbios/proc.c::proc_read_escd().  It's inside a sanity check,
so it probably won't trigger often (if at all), however it *is* a potential
leak and it's easy to avoid, so let's just fix it :)

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:51 -07:00

299 lines
7.2 KiB
C

/*
* /proc/bus/pnp interface for Plug and Play devices
*
* Written by David Hinds, dahinds@users.sourceforge.net
* Modified by Thomas Hood
*
* The .../devices and .../<node> and .../boot/<node> files are
* utilized by the lspnp and setpnp utilities, supplied with the
* pcmcia-cs package.
* http://pcmcia-cs.sourceforge.net
*
* The .../escd file is utilized by the lsescd utility written by
* Gunther Mayer.
* http://home.t-online.de/home/gunther.mayer/lsescd
*
* The .../legacy_device_resources file is not used yet.
*
* The other files are human-readable.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/pnpbios.h>
#include <linux/init.h>
#include <asm/uaccess.h>
#include "pnpbios.h"
static struct proc_dir_entry *proc_pnp = NULL;
static struct proc_dir_entry *proc_pnp_boot = NULL;
static int proc_read_pnpconfig(char *buf, char **start, off_t pos,
int count, int *eof, void *data)
{
struct pnp_isa_config_struc pnps;
if (pnp_bios_isapnp_config(&pnps))
return -EIO;
return snprintf(buf, count,
"structure_revision %d\n"
"number_of_CSNs %d\n"
"ISA_read_data_port 0x%x\n",
pnps.revision, pnps.no_csns, pnps.isa_rd_data_port);
}
static int proc_read_escdinfo(char *buf, char **start, off_t pos,
int count, int *eof, void *data)
{
struct escd_info_struc escd;
if (pnp_bios_escd_info(&escd))
return -EIO;
return snprintf(buf, count,
"min_ESCD_write_size %d\n"
"ESCD_size %d\n"
"NVRAM_base 0x%x\n",
escd.min_escd_write_size,
escd.escd_size, escd.nv_storage_base);
}
#define MAX_SANE_ESCD_SIZE (32*1024)
static int proc_read_escd(char *buf, char **start, off_t pos,
int count, int *eof, void *data)
{
struct escd_info_struc escd;
char *tmpbuf;
int escd_size, escd_left_to_read, n;
if (pnp_bios_escd_info(&escd))
return -EIO;
/* sanity check */
if (escd.escd_size > MAX_SANE_ESCD_SIZE) {
printk(KERN_ERR
"PnPBIOS: proc_read_escd: ESCD size reported by BIOS escd_info call is too great\n");
return -EFBIG;
}
tmpbuf = kzalloc(escd.escd_size, GFP_KERNEL);
if (!tmpbuf)
return -ENOMEM;
if (pnp_bios_read_escd(tmpbuf, escd.nv_storage_base)) {
kfree(tmpbuf);
return -EIO;
}
escd_size =
(unsigned char)(tmpbuf[0]) + (unsigned char)(tmpbuf[1]) * 256;
/* sanity check */
if (escd_size > MAX_SANE_ESCD_SIZE) {
printk(KERN_ERR "PnPBIOS: proc_read_escd: ESCD size reported by"
" BIOS read_escd call is too great\n");
kfree(tmpbuf);
return -EFBIG;
}
escd_left_to_read = escd_size - pos;
if (escd_left_to_read < 0)
escd_left_to_read = 0;
if (escd_left_to_read == 0)
*eof = 1;
n = min(count, escd_left_to_read);
memcpy(buf, tmpbuf + pos, n);
kfree(tmpbuf);
*start = buf;
return n;
}
static int proc_read_legacyres(char *buf, char **start, off_t pos,
int count, int *eof, void *data)
{
/* Assume that the following won't overflow the buffer */
if (pnp_bios_get_stat_res(buf))
return -EIO;
return count; // FIXME: Return actual length
}
static int proc_read_devices(char *buf, char **start, off_t pos,
int count, int *eof, void *data)
{
struct pnp_bios_node *node;
u8 nodenum;
char *p = buf;
if (pos >= 0xff)
return 0;
node = kzalloc(node_info.max_node_size, GFP_KERNEL);
if (!node)
return -ENOMEM;
for (nodenum = pos; nodenum < 0xff;) {
u8 thisnodenum = nodenum;
/* 26 = the number of characters per line sprintf'ed */
if ((p - buf + 26) > count)
break;
if (pnp_bios_get_dev_node(&nodenum, PNPMODE_DYNAMIC, node))
break;
p += sprintf(p, "%02x\t%08x\t%02x:%02x:%02x\t%04x\n",
node->handle, node->eisa_id,
node->type_code[0], node->type_code[1],
node->type_code[2], node->flags);
if (nodenum <= thisnodenum) {
printk(KERN_ERR
"%s Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
"PnPBIOS: proc_read_devices:",
(unsigned int)nodenum,
(unsigned int)thisnodenum);
*eof = 1;
break;
}
}
kfree(node);
if (nodenum == 0xff)
*eof = 1;
*start = (char *)((off_t) nodenum - pos);
return p - buf;
}
static int proc_read_node(char *buf, char **start, off_t pos,
int count, int *eof, void *data)
{
struct pnp_bios_node *node;
int boot = (long)data >> 8;
u8 nodenum = (long)data;
int len;
node = kzalloc(node_info.max_node_size, GFP_KERNEL);
if (!node)
return -ENOMEM;
if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
kfree(node);
return -EIO;
}
len = node->size - sizeof(struct pnp_bios_node);
memcpy(buf, node->data, len);
kfree(node);
return len;
}
static int proc_write_node(struct file *file, const char __user * buf,
unsigned long count, void *data)
{
struct pnp_bios_node *node;
int boot = (long)data >> 8;
u8 nodenum = (long)data;
int ret = count;
node = kzalloc(node_info.max_node_size, GFP_KERNEL);
if (!node)
return -ENOMEM;
if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
ret = -EIO;
goto out;
}
if (count != node->size - sizeof(struct pnp_bios_node)) {
ret = -EINVAL;
goto out;
}
if (copy_from_user(node->data, buf, count)) {
ret = -EFAULT;
goto out;
}
if (pnp_bios_set_dev_node(node->handle, boot, node) != 0) {
ret = -EINVAL;
goto out;
}
ret = count;
out:
kfree(node);
return ret;
}
int pnpbios_interface_attach_device(struct pnp_bios_node *node)
{
char name[3];
struct proc_dir_entry *ent;
sprintf(name, "%02x", node->handle);
if (!proc_pnp)
return -EIO;
if (!pnpbios_dont_use_current_config) {
ent = create_proc_entry(name, 0, proc_pnp);
if (ent) {
ent->read_proc = proc_read_node;
ent->write_proc = proc_write_node;
ent->data = (void *)(long)(node->handle);
}
}
if (!proc_pnp_boot)
return -EIO;
ent = create_proc_entry(name, 0, proc_pnp_boot);
if (ent) {
ent->read_proc = proc_read_node;
ent->write_proc = proc_write_node;
ent->data = (void *)(long)(node->handle + 0x100);
return 0;
}
return -EIO;
}
/*
* When this is called, pnpbios functions are assumed to
* work and the pnpbios_dont_use_current_config flag
* should already have been set to the appropriate value
*/
int __init pnpbios_proc_init(void)
{
proc_pnp = proc_mkdir("pnp", proc_bus);
if (!proc_pnp)
return -EIO;
proc_pnp_boot = proc_mkdir("boot", proc_pnp);
if (!proc_pnp_boot)
return -EIO;
create_proc_read_entry("devices", 0, proc_pnp, proc_read_devices, NULL);
create_proc_read_entry("configuration_info", 0, proc_pnp,
proc_read_pnpconfig, NULL);
create_proc_read_entry("escd_info", 0, proc_pnp, proc_read_escdinfo,
NULL);
create_proc_read_entry("escd", S_IRUSR, proc_pnp, proc_read_escd, NULL);
create_proc_read_entry("legacy_device_resources", 0, proc_pnp,
proc_read_legacyres, NULL);
return 0;
}
void __exit pnpbios_proc_exit(void)
{
int i;
char name[3];
if (!proc_pnp)
return;
for (i = 0; i < 0xff; i++) {
sprintf(name, "%02x", i);
if (!pnpbios_dont_use_current_config)
remove_proc_entry(name, proc_pnp);
remove_proc_entry(name, proc_pnp_boot);
}
remove_proc_entry("legacy_device_resources", proc_pnp);
remove_proc_entry("escd", proc_pnp);
remove_proc_entry("escd_info", proc_pnp);
remove_proc_entry("configuration_info", proc_pnp);
remove_proc_entry("devices", proc_pnp);
remove_proc_entry("boot", proc_pnp);
remove_proc_entry("pnp", proc_bus);
}