cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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proc.c (6832B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * /proc/bus/pnp interface for Plug and Play devices
      4 *
      5 * Written by David Hinds, dahinds@users.sourceforge.net
      6 * Modified by Thomas Hood
      7 *
      8 * The .../devices and .../<node> and .../boot/<node> files are
      9 * utilized by the lspnp and setpnp utilities, supplied with the
     10 * pcmcia-cs package.
     11 *     http://pcmcia-cs.sourceforge.net
     12 *
     13 * The .../escd file is utilized by the lsescd utility written by
     14 * Gunther Mayer.
     15 *
     16 * The .../legacy_device_resources file is not used yet.
     17 *
     18 * The other files are human-readable.
     19 */
     20
     21#include <linux/module.h>
     22#include <linux/kernel.h>
     23#include <linux/slab.h>
     24#include <linux/types.h>
     25#include <linux/proc_fs.h>
     26#include <linux/pnp.h>
     27#include <linux/seq_file.h>
     28#include <linux/init.h>
     29
     30#include <linux/uaccess.h>
     31
     32#include "pnpbios.h"
     33
     34static struct proc_dir_entry *proc_pnp = NULL;
     35static struct proc_dir_entry *proc_pnp_boot = NULL;
     36
     37static int pnpconfig_proc_show(struct seq_file *m, void *v)
     38{
     39	struct pnp_isa_config_struc pnps;
     40
     41	if (pnp_bios_isapnp_config(&pnps))
     42		return -EIO;
     43	seq_printf(m, "structure_revision %d\n"
     44		      "number_of_CSNs %d\n"
     45		      "ISA_read_data_port 0x%x\n",
     46		   pnps.revision, pnps.no_csns, pnps.isa_rd_data_port);
     47	return 0;
     48}
     49
     50static int escd_info_proc_show(struct seq_file *m, void *v)
     51{
     52	struct escd_info_struc escd;
     53
     54	if (pnp_bios_escd_info(&escd))
     55		return -EIO;
     56	seq_printf(m, "min_ESCD_write_size %d\n"
     57			"ESCD_size %d\n"
     58			"NVRAM_base 0x%x\n",
     59			escd.min_escd_write_size,
     60			escd.escd_size, escd.nv_storage_base);
     61	return 0;
     62}
     63
     64#define MAX_SANE_ESCD_SIZE (32*1024)
     65static int escd_proc_show(struct seq_file *m, void *v)
     66{
     67	struct escd_info_struc escd;
     68	char *tmpbuf;
     69	int escd_size;
     70
     71	if (pnp_bios_escd_info(&escd))
     72		return -EIO;
     73
     74	/* sanity check */
     75	if (escd.escd_size > MAX_SANE_ESCD_SIZE) {
     76		printk(KERN_ERR
     77		       "PnPBIOS: %s: ESCD size reported by BIOS escd_info call is too great\n", __func__);
     78		return -EFBIG;
     79	}
     80
     81	tmpbuf = kzalloc(escd.escd_size, GFP_KERNEL);
     82	if (!tmpbuf)
     83		return -ENOMEM;
     84
     85	if (pnp_bios_read_escd(tmpbuf, escd.nv_storage_base)) {
     86		kfree(tmpbuf);
     87		return -EIO;
     88	}
     89
     90	escd_size =
     91	    (unsigned char)(tmpbuf[0]) + (unsigned char)(tmpbuf[1]) * 256;
     92
     93	/* sanity check */
     94	if (escd_size > MAX_SANE_ESCD_SIZE) {
     95		printk(KERN_ERR "PnPBIOS: %s: ESCD size reported by"
     96				" BIOS read_escd call is too great\n", __func__);
     97		kfree(tmpbuf);
     98		return -EFBIG;
     99	}
    100
    101	seq_write(m, tmpbuf, escd_size);
    102	kfree(tmpbuf);
    103	return 0;
    104}
    105
    106static int pnp_legacyres_proc_show(struct seq_file *m, void *v)
    107{
    108	void *buf;
    109
    110	buf = kmalloc(65536, GFP_KERNEL);
    111	if (!buf)
    112		return -ENOMEM;
    113	if (pnp_bios_get_stat_res(buf)) {
    114		kfree(buf);
    115		return -EIO;
    116	}
    117
    118	seq_write(m, buf, 65536);
    119	kfree(buf);
    120	return 0;
    121}
    122
    123static int pnp_devices_proc_show(struct seq_file *m, void *v)
    124{
    125	struct pnp_bios_node *node;
    126	u8 nodenum;
    127
    128	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
    129	if (!node)
    130		return -ENOMEM;
    131
    132	for (nodenum = 0; nodenum < 0xff;) {
    133		u8 thisnodenum = nodenum;
    134
    135		if (pnp_bios_get_dev_node(&nodenum, PNPMODE_DYNAMIC, node))
    136			break;
    137		seq_printf(m, "%02x\t%08x\t%3phC\t%04x\n",
    138			     node->handle, node->eisa_id,
    139			     node->type_code, node->flags);
    140		if (nodenum <= thisnodenum) {
    141			printk(KERN_ERR
    142			       "%s Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
    143			       "PnPBIOS: proc_read_devices:",
    144			       (unsigned int)nodenum,
    145			       (unsigned int)thisnodenum);
    146			break;
    147		}
    148	}
    149	kfree(node);
    150	return 0;
    151}
    152
    153static int pnpbios_proc_show(struct seq_file *m, void *v)
    154{
    155	void *data = m->private;
    156	struct pnp_bios_node *node;
    157	int boot = (long)data >> 8;
    158	u8 nodenum = (long)data;
    159	int len;
    160
    161	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
    162	if (!node)
    163		return -ENOMEM;
    164	if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
    165		kfree(node);
    166		return -EIO;
    167	}
    168	len = node->size - sizeof(struct pnp_bios_node);
    169	seq_write(m, node->data, len);
    170	kfree(node);
    171	return 0;
    172}
    173
    174static int pnpbios_proc_open(struct inode *inode, struct file *file)
    175{
    176	return single_open(file, pnpbios_proc_show, pde_data(inode));
    177}
    178
    179static ssize_t pnpbios_proc_write(struct file *file, const char __user *buf,
    180				  size_t count, loff_t *pos)
    181{
    182	void *data = pde_data(file_inode(file));
    183	struct pnp_bios_node *node;
    184	int boot = (long)data >> 8;
    185	u8 nodenum = (long)data;
    186	int ret = count;
    187
    188	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
    189	if (!node)
    190		return -ENOMEM;
    191	if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
    192		ret = -EIO;
    193		goto out;
    194	}
    195	if (count != node->size - sizeof(struct pnp_bios_node)) {
    196		ret = -EINVAL;
    197		goto out;
    198	}
    199	if (copy_from_user(node->data, buf, count)) {
    200		ret = -EFAULT;
    201		goto out;
    202	}
    203	if (pnp_bios_set_dev_node(node->handle, boot, node) != 0) {
    204		ret = -EINVAL;
    205		goto out;
    206	}
    207	ret = count;
    208out:
    209	kfree(node);
    210	return ret;
    211}
    212
    213static const struct proc_ops pnpbios_proc_ops = {
    214	.proc_open	= pnpbios_proc_open,
    215	.proc_read	= seq_read,
    216	.proc_lseek	= seq_lseek,
    217	.proc_release	= single_release,
    218	.proc_write	= pnpbios_proc_write,
    219};
    220
    221int pnpbios_interface_attach_device(struct pnp_bios_node *node)
    222{
    223	char name[3];
    224
    225	sprintf(name, "%02x", node->handle);
    226
    227	if (!proc_pnp)
    228		return -EIO;
    229	if (!pnpbios_dont_use_current_config) {
    230		proc_create_data(name, 0644, proc_pnp, &pnpbios_proc_ops,
    231				 (void *)(long)(node->handle));
    232	}
    233
    234	if (!proc_pnp_boot)
    235		return -EIO;
    236	if (proc_create_data(name, 0644, proc_pnp_boot, &pnpbios_proc_ops,
    237			     (void *)(long)(node->handle + 0x100)))
    238		return 0;
    239	return -EIO;
    240}
    241
    242/*
    243 * When this is called, pnpbios functions are assumed to
    244 * work and the pnpbios_dont_use_current_config flag
    245 * should already have been set to the appropriate value
    246 */
    247int __init pnpbios_proc_init(void)
    248{
    249	proc_pnp = proc_mkdir("bus/pnp", NULL);
    250	if (!proc_pnp)
    251		return -EIO;
    252	proc_pnp_boot = proc_mkdir("boot", proc_pnp);
    253	if (!proc_pnp_boot)
    254		return -EIO;
    255	proc_create_single("devices", 0, proc_pnp, pnp_devices_proc_show);
    256	proc_create_single("configuration_info", 0, proc_pnp,
    257			pnpconfig_proc_show);
    258	proc_create_single("escd_info", 0, proc_pnp, escd_info_proc_show);
    259	proc_create_single("escd", S_IRUSR, proc_pnp, escd_proc_show);
    260	proc_create_single("legacy_device_resources", 0, proc_pnp,
    261			pnp_legacyres_proc_show);
    262	return 0;
    263}
    264
    265void __exit pnpbios_proc_exit(void)
    266{
    267	int i;
    268	char name[3];
    269
    270	if (!proc_pnp)
    271		return;
    272
    273	for (i = 0; i < 0xff; i++) {
    274		sprintf(name, "%02x", i);
    275		if (!pnpbios_dont_use_current_config)
    276			remove_proc_entry(name, proc_pnp);
    277		remove_proc_entry(name, proc_pnp_boot);
    278	}
    279	remove_proc_entry("legacy_device_resources", proc_pnp);
    280	remove_proc_entry("escd", proc_pnp);
    281	remove_proc_entry("escd_info", proc_pnp);
    282	remove_proc_entry("configuration_info", proc_pnp);
    283	remove_proc_entry("devices", proc_pnp);
    284	remove_proc_entry("boot", proc_pnp);
    285	remove_proc_entry("bus/pnp", NULL);
    286}