Systemd/namedev.c
olh@suse.de 4474484153 [PATCH] uninitialized variable for mknod and friend
mknod gets an uninitialized variable, which leads to interesting file
modes. the bug is in namedev, devices with no match must not use the
uninitialized stuff were dev points to.
2005-04-26 21:35:10 -07:00

889 lines
22 KiB
C

/*
* namedev.c
*
* Userspace devfs
*
* Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
*
*
* 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 version 2 of the License.
*
* 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 <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <ctype.h>
#include <unistd.h>
#include <errno.h>
#include <time.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include "libsysfs/sysfs/libsysfs.h"
#include "list.h"
#include "udev.h"
#include "udev_lib.h"
#include "udev_version.h"
#include "logging.h"
#include "namedev.h"
#include "klibc_fixups.h"
static struct sysfs_attribute *find_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device, char *attr);
LIST_HEAD(config_device_list);
LIST_HEAD(perm_device_list);
/* compare string with pattern (supports * ? [0-9] [!A-Z]) */
static int strcmp_pattern(const char *p, const char *s)
{
if (s[0] == '\0') {
while (p[0] == '*')
p++;
return (p[0] != '\0');
}
switch (p[0]) {
case '[':
{
int not = 0;
p++;
if (p[0] == '!') {
not = 1;
p++;
}
while ((p[0] != '\0') && (p[0] != ']')) {
int match = 0;
if (p[1] == '-') {
if ((s[0] >= p[0]) && (s[0] <= p[2]))
match = 1;
p += 3;
} else {
match = (p[0] == s[0]);
p++;
}
if (match ^ not) {
while ((p[0] != '\0') && (p[0] != ']'))
p++;
if (p[0] == ']')
return strcmp_pattern(p+1, s+1);
}
}
}
break;
case '*':
if (strcmp_pattern(p, s+1))
return strcmp_pattern(p+1, s);
return 0;
case '\0':
if (s[0] == '\0') {
return 0;
}
break;
default:
if ((p[0] == s[0]) || (p[0] == '?'))
return strcmp_pattern(p+1, s+1);
break;
}
return 1;
}
static struct perm_device *find_perm(char *name)
{
struct perm_device *perm;
list_for_each_entry(perm, &perm_device_list, node) {
if (strcmp_pattern(perm->name, name))
continue;
return perm;
}
return NULL;
}
static mode_t get_default_mode(void)
{
mode_t mode = 0600; /* default to owner rw only */
if (strlen(default_mode_str) != 0)
mode = strtol(default_mode_str, NULL, 8);
return mode;
}
static char *get_default_owner(void)
{
if (strlen(default_owner_str) == 0)
strfieldcpy(default_owner_str, "root");
return default_owner_str;
}
static char *get_default_group(void)
{
if (strlen(default_group_str) == 0)
strfieldcpy(default_group_str, "root");
return default_group_str;
}
/* extract possible {attr} and move str behind it */
static char *get_format_attribute(char **str)
{
char *pos;
char *attr = NULL;
if (*str[0] == '{') {
pos = strchr(*str, '}');
if (pos == NULL) {
dbg("missing closing brace for format");
return NULL;
}
pos[0] = '\0';
attr = *str+1;
*str = pos+1;
dbg("attribute='%s', str='%s'", attr, *str);
}
return attr;
}
/* extract possible format length and move str behind it*/
static int get_format_len(char **str)
{
int num;
char *tail;
if (isdigit(*str[0])) {
num = (int) strtoul(*str, &tail, 10);
if (num > 0) {
*str = tail;
dbg("format length=%i", num);
return num;
} else {
dbg("format parsing error '%s'", *str);
}
}
return -1;
}
static void apply_format(struct udevice *udev, char *string, size_t maxsize,
struct sysfs_class_device *class_dev,
struct sysfs_device *sysfs_device)
{
char temp[NAME_SIZE];
char temp2[NAME_SIZE];
char *tail;
char *pos;
char *attr;
int len;
int i;
char c;
char *spos;
char *rest;
int slen;
struct sysfs_attribute *tmpattr;
pos = string;
while (1) {
pos = strchr(string, '%');
if (pos != NULL) {
pos[0] = '\0';
tail = pos+1;
len = get_format_len(&tail);
c = tail[0];
strfieldcpy(temp, tail+1);
tail = temp;
} else {
break;
}
dbg("format=%c, string='%s', tail='%s'",c , string, tail);
attr = get_format_attribute(&tail);
switch (c) {
case 'b':
if (strlen(udev->bus_id) == 0)
break;
strfieldcatmax(string, udev->bus_id, maxsize);
dbg("substitute bus_id '%s'", udev->bus_id);
break;
case 'k':
if (strlen(udev->kernel_name) == 0)
break;
strfieldcatmax(string, udev->kernel_name, maxsize);
dbg("substitute kernel name '%s'", udev->kernel_name);
break;
case 'n':
if (strlen(udev->kernel_number) == 0)
break;
strfieldcatmax(string, udev->kernel_number, maxsize);
dbg("substitute kernel number '%s'", udev->kernel_number);
break;
case 'm':
strintcatmax(string, udev->minor, maxsize);
dbg("substitute minor number '%u'", udev->minor);
break;
case 'M':
strintcatmax(string, udev->major, maxsize);
dbg("substitute major number '%u'", udev->major);
break;
case 'c':
if (strlen(udev->program_result) == 0)
break;
/* get part part of the result string */
i = 0;
if (attr != NULL)
i = strtoul(attr, &rest, 10);
if (i > 0) {
foreach_strpart(udev->program_result, " \n\r", spos, slen) {
i--;
if (i == 0)
break;
}
if (i > 0) {
dbg("requested part of result string not found");
break;
}
if (rest[0] == '+')
strfieldcpy(temp2, spos);
else
strfieldcpymax(temp2, spos, slen+1);
strfieldcatmax(string, temp2, maxsize);
dbg("substitute part of result string '%s'", temp2);
} else {
strfieldcatmax(string, udev->program_result, maxsize);
dbg("substitute result string '%s'", udev->program_result);
}
break;
case 's':
if (attr != NULL) {
tmpattr = find_sysfs_attribute(class_dev, sysfs_device, attr);
if (tmpattr == NULL) {
dbg("sysfa attribute '%s' not found", attr);
break;
}
strfieldcatmax(string, tmpattr->value, maxsize);
dbg("substitute sysfs value '%s'", tmpattr->value);
} else {
dbg("missing attribute");
}
break;
case '%':
strfieldcatmax(string, "%", maxsize);
break;
default:
dbg("unknown substitution type '%%%c'", c);
break;
}
/* truncate to specified length */
if (len > 0)
pos[len] = '\0';
strfieldcatmax(string, tail, maxsize);
}
}
/*
* Note, we can have multiple files for different busses in here due
* to the mess that USB has for its device tree...
*/
static struct bus_file {
char *bus;
char *file;
} bus_files[] = {
{ .bus = "scsi", .file = "vendor" },
{ .bus = "usb", .file = "idVendor" },
{ .bus = "usb", .file = "iInterface" },
{ .bus = "usb-serial", .file = "detach_state" },
{ .bus = "ide", .file = "detach_state" },
{ .bus = "pci", .file = "vendor" },
{}
};
#define SECONDS_TO_WAIT_FOR_FILE 10
static void wait_for_device_to_initialize(struct sysfs_device *sysfs_device)
{
/* sleep until we see the file for this specific bus type show up this
* is needed because we can easily out-run the kernel in looking for
* these files before the paticular subsystem has created them in the
* sysfs tree properly.
*
* And people thought that the /sbin/hotplug event system was going to
* be slow, poo on you for arguing that before even testing it...
*/
struct bus_file *b = &bus_files[0];
struct sysfs_attribute *tmpattr;
int found = 0;
int loop = SECONDS_TO_WAIT_FOR_FILE;
while (1) {
if (b->bus == NULL) {
if (!found)
break;
/* sleep to give the kernel a chance to create the file */
sleep(1);
--loop;
if (loop == 0)
break;
b = &bus_files[0];
}
if (strcmp(sysfs_device->bus, b->bus) == 0) {
found = 1;
dbg("looking for file '%s' on bus '%s'", b->file, b->bus);
tmpattr = sysfs_get_device_attr(sysfs_device, b->file);
if (tmpattr) {
/* found it! */
goto exit;
}
dbg("can't find '%s' file", b->file);
}
++b;
}
if (!found)
dbg("did not find bus type '%s' on list of bus_id_files, "
"contact greg@kroah.com", sysfs_device->bus);
exit:
return; /* here to prevent compiler warning... */
}
static void fix_kernel_name(struct udevice *udev)
{
char *temp = udev->kernel_name;
while (*temp != 0x00) {
/* Some block devices have a ! in their name,
* we need to change that to / */
if (*temp == '!')
*temp = '/';
++temp;
}
}
static int execute_program(char *path, char *value, int len)
{
int retval;
int count;
int status;
int fds[2];
pid_t pid;
char *pos;
char arg[PROGRAM_SIZE];
char *argv[sizeof(arg) / 2];
int i;
i = 0;
if (strchr(path, ' ')) {
strfieldcpy(arg, path);
pos = arg;
while (pos != NULL) {
if (pos[0] == '\'') {
/* don't separate if in apostrophes */
pos++;
argv[i] = strsep(&pos, "\'");
while (pos[0] == ' ')
pos++;
} else {
argv[i] = strsep(&pos, " ");
}
dbg("arg[%i] '%s'", i, argv[i]);
i++;
}
}
argv[i] = NULL;
retval = pipe(fds);
if (retval != 0) {
dbg("pipe failed");
return -1;
}
pid = fork();
switch(pid) {
case 0:
/* child */
close(STDOUT_FILENO);
/* dup write side of pipe to STDOUT */
dup(fds[1]);
if (argv[0] != NULL) {
dbg("execute '%s' with given arguments", argv[0]);
retval = execv(argv[0], argv);
} else {
dbg("execute '%s' with main argument", path);
retval = execv(path, main_argv);
}
info(FIELD_PROGRAM " execution of '%s' failed", path);
exit(1);
case -1:
dbg("fork failed");
return -1;
default:
/* parent reads from fds[0] */
close(fds[1]);
retval = 0;
i = 0;
while (1) {
count = read(fds[0], value + i, len - i-1);
if (count <= 0)
break;
i += count;
if (i >= len-1) {
dbg("result len %d too short", len);
retval = -1;
break;
}
}
if (count < 0) {
dbg("read failed with '%s'", strerror(errno));
retval = -1;
}
if (i > 0 && value[i] == '\n')
i--;
value[i] = '\0';
dbg("result is '%s'", value);
close(fds[0]);
wait(&status);
if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0)) {
dbg("exec program status 0x%x", status);
retval = -1;
}
}
return retval;
}
static struct sysfs_attribute *find_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device, char *attr)
{
struct sysfs_attribute *tmpattr = NULL;
char *c;
dbg("look for device attribute '%s'", attr);
/* try to find the attribute in the class device directory */
tmpattr = sysfs_get_classdev_attr(class_dev, attr);
if (tmpattr)
goto attr_found;
/* look in the class device directory if present */
if (sysfs_device) {
tmpattr = sysfs_get_device_attr(sysfs_device, attr);
if (tmpattr)
goto attr_found;
}
return NULL;
attr_found:
c = strchr(tmpattr->value, '\n');
if (c != NULL)
c[0] = '\0';
dbg("found attribute '%s'", tmpattr->path);
return tmpattr;
}
static int compare_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device, struct sysfs_pair *pair)
{
struct sysfs_attribute *tmpattr;
int i;
int len;
if ((pair == NULL) || (pair->file[0] == '\0') || (pair->value == '\0'))
return -ENODEV;
tmpattr = find_sysfs_attribute(class_dev, sysfs_device, pair->file);
if (tmpattr == NULL)
return -ENODEV;
/* strip trailing whitespace of value, if not asked to match for it */
if (! isspace(pair->value[strlen(pair->value)-1])) {
i = len = strlen(tmpattr->value);
while (i > 0 && isspace(tmpattr->value[i-1]))
i--;
if (i < len) {
tmpattr->value[i] = '\0';
dbg("remove %i trailing whitespace chars from '%s'",
len - i, tmpattr->value);
}
}
dbg("compare attribute '%s' value '%s' with '%s'",
pair->file, tmpattr->value, pair->value);
if (strcmp_pattern(pair->value, tmpattr->value) != 0)
return -ENODEV;
dbg("found matching attribute '%s' with value '%s'",
pair->file, pair->value);
return 0;
}
static int match_sysfs_pairs(struct config_device *dev, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device)
{
struct sysfs_pair *pair;
int i;
for (i = 0; i < MAX_SYSFS_PAIRS; ++i) {
pair = &dev->sysfs_pair[i];
if ((pair->file[0] == '\0') || (pair->value[0] == '\0'))
break;
if (compare_sysfs_attribute(class_dev, sysfs_device, pair) != 0) {
dbg("sysfs attribute doesn't match");
return -ENODEV;
}
}
return 0;
}
static int match_id(struct config_device *dev, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device)
{
char path[SYSFS_PATH_MAX];
char *temp = NULL;
/* we have to have a sysfs device for ID to work */
if (!sysfs_device)
return -ENODEV;
strfieldcpy(path, sysfs_device->path);
temp = strrchr(path, '/');
temp++;
dbg("search '%s' in '%s', path='%s'", dev->id, temp, path);
if (strcmp_pattern(dev->id, temp) != 0)
return -ENODEV;
else
return 0;
}
static int match_place(struct config_device *dev, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device)
{
char path[SYSFS_PATH_MAX];
int found;
char *temp = NULL;
/* we have to have a sysfs device for PLACE to work */
if (!sysfs_device)
return -ENODEV;
found = 0;
strfieldcpy(path, sysfs_device->path);
temp = strrchr(path, '/');
dbg("search '%s' in '%s', path='%s'", dev->place, temp, path);
if (strstr(temp, dev->place) != NULL) {
found = 1;
} else {
*temp = 0x00;
temp = strrchr(path, '/');
dbg("search '%s' in '%s', path='%s'", dev->place, temp, path);
if (strstr(temp, dev->place) != NULL)
found = 1;
}
if (!found) {
dbg("place doesn't match");
return -ENODEV;
}
return 0;
}
static struct sysfs_device *get_sysfs_device(struct sysfs_class_device *class_dev)
{
struct sysfs_device *sysfs_device;
struct sysfs_class_device *class_dev_parent;
struct timespec tspec;
int loop;
/* Figure out where the device symlink is at. For char devices this will
* always be in the class_dev->path. But for block devices, it's different.
* The main block device will have the device symlink in it's path, but
* all partitions have the symlink in its parent directory.
* But we need to watch out for block devices that do not have parents, yet
* look like a partition (fd0, loop0, etc.) They all do not have a device
* symlink yet. We do sit and spin on waiting for them right now, we should
* possibly have a whitelist for these devices here...
*/
class_dev_parent = sysfs_get_classdev_parent(class_dev);
if (class_dev_parent)
dbg("Really a partition");
tspec.tv_sec = 0;
tspec.tv_nsec = 10000000; /* sleep 10 millisec */
loop = 10;
while (loop--) {
if (udev_sleep)
nanosleep(&tspec, NULL);
if (class_dev_parent)
sysfs_device = sysfs_get_classdev_device(class_dev_parent);
else
sysfs_device = sysfs_get_classdev_device(class_dev);
if (sysfs_device != NULL)
goto device_found;
}
dbg("timed out waiting for device symlink, continuing on anyway...");
device_found:
/* We have another issue with just the wait above - the sysfs part of
* the kernel may not be quick enough to have created the link to the
* device under the "bus" subsystem. Due to this, the sysfs_device->bus
* will not contain the actual bus name :(
*
* Libsysfs now provides a new API sysfs_get_device_bus(), so use it
* if needed
*/
if (sysfs_device) {
if (sysfs_device->bus[0] != '\0')
goto bus_found;
loop = 10;
tspec.tv_nsec = 10000000;
while (loop--) {
if (udev_sleep)
nanosleep(&tspec, NULL);
sysfs_get_device_bus(sysfs_device);
if (sysfs_device->bus[0] != '\0')
goto bus_found;
}
dbg("timed out waiting to find the device bus, continuing on anyway");
goto exit;
bus_found:
dbg("device %s is registered with bus '%s'",
sysfs_device->name, sysfs_device->bus);
}
exit:
return sysfs_device;
}
static int match_rule(struct config_device *dev, struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
{
while (1) {
/* check for matching bus value */
if (dev->bus[0] != '\0') {
if (sysfs_device == NULL) {
dbg("device has no bus");
goto try_parent;
}
dbg("check for " FIELD_BUS " dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
if (strcmp_pattern(dev->bus, sysfs_device->bus) != 0) {
dbg(FIELD_BUS " is not matching");
goto try_parent;
} else {
dbg(FIELD_BUS " matches");
}
}
/* check for matching kernel name*/
if (dev->kernel[0] != '\0') {
dbg("check for " FIELD_KERNEL " dev->kernel='%s' class_dev->name='%s'", dev->kernel, class_dev->name);
if (strcmp_pattern(dev->kernel, class_dev->name) != 0) {
dbg(FIELD_KERNEL " is not matching");
goto try_parent;
} else {
dbg(FIELD_KERNEL " matches");
}
}
/* check for matching bus id */
if (dev->id[0] != '\0') {
dbg("check " FIELD_ID);
if (match_id(dev, class_dev, sysfs_device) != 0) {
dbg(FIELD_ID " is not matching");
goto try_parent;
} else {
dbg(FIELD_ID " matches");
}
}
/* check for matching place of device */
if (dev->place[0] != '\0') {
dbg("check " FIELD_PLACE);
if (match_place(dev, class_dev, sysfs_device) != 0) {
dbg(FIELD_PLACE " is not matching");
goto try_parent;
} else {
dbg(FIELD_PLACE " matches");
}
}
/* check for matching sysfs pairs */
if (dev->sysfs_pair[0].file[0] != '\0') {
dbg("check " FIELD_SYSFS " pairs");
if (match_sysfs_pairs(dev, class_dev, sysfs_device) != 0) {
dbg(FIELD_SYSFS " is not matching");
goto try_parent;
} else {
dbg(FIELD_SYSFS " matches");
}
}
/* execute external program */
if (dev->program[0] != '\0') {
dbg("check " FIELD_PROGRAM);
apply_format(udev, dev->program, sizeof(dev->program),
class_dev, sysfs_device);
if (execute_program(dev->program, udev->program_result, NAME_SIZE) != 0) {
dbg(FIELD_PROGRAM " returned nonzero");
goto try_parent;
} else {
dbg(FIELD_PROGRAM " returned successful");
}
}
/* check for matching result of external program */
if (dev->result[0] != '\0') {
dbg("check for " FIELD_RESULT
" dev->result='%s', udev->program_result='%s'",
dev->result, udev->program_result);
if (strcmp_pattern(dev->result, udev->program_result) != 0) {
dbg(FIELD_RESULT " is not matching");
goto try_parent;
} else {
dbg(FIELD_RESULT " matches");
}
}
/* Yeah, we matched! */
return 0;
try_parent:
dbg("try parent sysfs device");
sysfs_device = sysfs_get_device_parent(sysfs_device);
if (sysfs_device == NULL)
return -ENODEV;
dbg("sysfs_device->path='%s'", sysfs_device->path);
dbg("sysfs_device->bus_id='%s'", sysfs_device->bus_id);
dbg("sysfs_device->bus='%s'", sysfs_device->bus);
}
}
int namedev_name_device(struct sysfs_class_device *class_dev, struct udevice *udev)
{
struct sysfs_device *sysfs_device = NULL;
struct config_device *dev;
struct perm_device *perm;
char *pos;
udev->mode = 0;
/* find the sysfs_device associated with this class device */
sysfs_device = get_sysfs_device(class_dev);
if (sysfs_device) {
dbg("sysfs_device->path='%s'", sysfs_device->path);
dbg("sysfs_device->bus_id='%s'", sysfs_device->bus_id);
dbg("sysfs_device->bus='%s'", sysfs_device->bus);
strfieldcpy(udev->bus_id, sysfs_device->bus_id);
wait_for_device_to_initialize(sysfs_device);
}
dbg("class_dev->name = '%s'", class_dev->name);
strfieldcpy(udev->kernel_name, class_dev->name);
fix_kernel_name(udev);
dbg("udev->kernel_name = '%s'", udev->kernel_name);
/* get kernel number */
pos = class_dev->name + strlen(class_dev->name);
while (isdigit(*(pos-1)))
pos--;
strfieldcpy(udev->kernel_number, pos);
dbg("kernel_number='%s'", udev->kernel_number);
/* look for a matching rule to apply */
list_for_each_entry(dev, &config_device_list, node) {
dbg("process rule");
if (match_rule(dev, class_dev, udev, sysfs_device) == 0) {
if (dev->name[0] == '\0' && dev->symlink[0] == '\0') {
info("configured rule in '%s' at line %i applied, '%s' is ignored",
dev->config_file, dev->config_line, udev->kernel_name);
return -1;
}
if (dev->symlink[0] != '\0') {
info("configured rule in '%s' at line %i applied, added symlink '%s'",
dev->config_file, dev->config_line, dev->symlink);
if (udev->symlink[0] != '\0')
strfieldcat(udev->symlink, " ");
strfieldcat(udev->symlink, dev->symlink);
}
if (dev->name[0] != '\0') {
info("configured rule in '%s' at line %i applied, '%s' becomes '%s'",
dev->config_file, dev->config_line, udev->kernel_name, dev->name);
strfieldcpy(udev->name, dev->name);
goto found;
}
}
}
/* no rule was found so we use the kernel name */
strfieldcpy(udev->name, udev->kernel_name);
goto done;
found:
apply_format(udev, udev->name, sizeof(udev->name), class_dev, sysfs_device);
apply_format(udev, udev->symlink, sizeof(udev->symlink), class_dev, sysfs_device);
udev->partitions = dev->partitions;
strfieldcpy(udev->config_file, dev->config_file);
udev->config_line = dev->config_line;
/* get permissions given in rule */
set_empty_perms(udev, dev->mode,
dev->owner,
dev->group);
done:
/* get permissions given in config file or set defaults */
perm = find_perm(udev->name);
if (perm != NULL) {
set_empty_perms(udev, perm->mode,
perm->owner,
perm->group);
} else {
set_empty_perms(udev, get_default_mode(),
get_default_owner(),
get_default_group());
}
dbg("name, '%s' is going to have owner='%s', group='%s', mode = %#o",
udev->name, udev->owner, udev->group, udev->mode);
/* store time of action */
udev->config_time = time(NULL);
return 0;
}
int namedev_init(void)
{
int retval;
retval = namedev_init_rules();
if (retval)
return retval;
retval = namedev_init_permissions();
if (retval)
return retval;
dump_config_dev_list();
dump_perm_dev_list();
return retval;
}