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mirror of https://github.com/systemd/systemd-stable.git synced 2024-10-30 14:55:26 +03:00
systemd-stable/namedev_parse.c
kay.sievers@vrfy.org 3db7fa2702 [PATCH] fix udev segfaults with bad permissions file
On Tue, Sep 14, 2004 at 02:53:12PM +0200, Loleslaw wrote:
> Hi,
> Since I started using udev-031 on my gentoo udevstart would just segfault
> (udev-030 worked). As it turned out I had a file in /etc/udev/permissions.d
> with a single space in one line. I've cleaned the file and it works all
> right, but I thought you could be interested.
> I've traced it to function namedev_init_permissions in namedev_parse.c
> I don't know C well enough to suggest a patch.

Yeah, thanks for pointing that out. It only happens if the file ends with
whitespace-only lines. Here is a fix and a test for udev-test.pl to
cover that case.
2005-04-26 21:37:01 -07:00

467 lines
10 KiB
C

/*
* namedev_parse.c
*
* Userspace devfs
*
* Copyright (C) 2003,2004 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.
*
*/
#ifdef DEBUG
/* define this to enable parsing debugging also */
/* #define DEBUG_PARSER */
#endif
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <ctype.h>
#include <unistd.h>
#include <sys/stat.h>
#include <errno.h>
#include "udev.h"
#include "udev_lib.h"
#include "logging.h"
#include "namedev.h"
static int add_config_dev(struct config_device *new_dev)
{
struct config_device *tmp_dev;
tmp_dev = malloc(sizeof(*tmp_dev));
if (tmp_dev == NULL)
return -ENOMEM;
memcpy(tmp_dev, new_dev, sizeof(*tmp_dev));
list_add_tail(&tmp_dev->node, &config_device_list);
//dump_config_dev(tmp_dev);
return 0;
}
void dump_config_dev(struct config_device *dev)
{
dbg_parse("name='%s', symlink='%s', bus='%s', place='%s', id='%s', "
"sysfs_file[0]='%s', sysfs_value[0]='%s', "
"kernel='%s', program='%s', result='%s'"
"owner='%s', group='%s', mode=%#o",
dev->name, dev->symlink, dev->bus, dev->place, dev->id,
dev->sysfs_pair[0].file, dev->sysfs_pair[0].value,
dev->kernel, dev->program, dev->result,
dev->owner, dev->group, dev->mode);
}
void dump_config_dev_list(void)
{
struct config_device *dev;
list_for_each_entry(dev, &config_device_list, node)
dump_config_dev(dev);
}
static int add_perm_dev(struct perm_device *new_dev)
{
struct perm_device *dev;
struct perm_device *tmp_dev;
/* update the values if we already have the device */
list_for_each_entry(dev, &perm_device_list, node) {
if (strcmp(new_dev->name, dev->name) != 0)
continue;
set_empty_perms(dev, new_dev->mode, new_dev->owner, new_dev->group);
return 0;
}
/* not found, add new structure to the perm list */
tmp_dev = malloc(sizeof(*tmp_dev));
if (!tmp_dev)
return -ENOMEM;
memcpy(tmp_dev, new_dev, sizeof(*tmp_dev));
list_add_tail(&tmp_dev->node, &perm_device_list);
//dump_perm_dev(tmp_dev);
return 0;
}
void dump_perm_dev(struct perm_device *dev)
{
dbg_parse("name='%s', owner='%s', group='%s', mode=%#o",
dev->name, dev->owner, dev->group, dev->mode);
}
void dump_perm_dev_list(void)
{
struct perm_device *dev;
list_for_each_entry(dev, &perm_device_list, node)
dump_perm_dev(dev);
}
/* extract possible KEY{attr} or KEY_attr */
static char *get_key_attribute(char *str)
{
char *pos;
char *attr;
attr = strchr(str, '{');
if (attr != NULL) {
attr++;
pos = strchr(attr, '}');
if (pos == NULL) {
dbg("missing closing brace for format");
return NULL;
}
pos[0] = '\0';
dbg("attribute='%s'", attr);
return attr;
}
attr = strchr(str, '_');
if (attr != NULL) {
attr++;
dbg("attribute='%s'", attr);
return attr;
}
return NULL;
}
static int namedev_parse_rules(char *filename)
{
char line[LINE_SIZE];
char *bufline;
int lineno;
char *temp;
char *temp2;
char *temp3;
char *attr;
char *buf;
size_t bufsize;
size_t cur;
size_t count;
int program_given = 0;
int valid;
int retval = 0;
struct config_device dev;
if (file_map(filename, &buf, &bufsize) == 0) {
dbg("reading '%s' as rules file", filename);
} else {
dbg("can't open '%s' as rules file", filename);
return -1;
}
/* loop through the whole file */
cur = 0;
lineno = 0;
while (cur < bufsize) {
count = buf_get_line(buf, bufsize, cur);
bufline = &buf[cur];
cur += count+1;
lineno++;
if (count >= LINE_SIZE) {
info("line too long, rule skipped %s, line %d",
filename, lineno);
continue;
}
/* eat the whitespace */
while ((count > 0) && isspace(bufline[0])) {
bufline++;
count--;
}
if (count == 0)
continue;
/* see if this is a comment */
if (bufline[0] == COMMENT_CHARACTER)
continue;
strncpy(line, bufline, count);
line[count] = '\0';
dbg_parse("read '%s'", line);
/* get all known keys */
memset(&dev, 0x00, sizeof(struct config_device));
temp = line;
valid = 0;
while (1) {
retval = parse_get_pair(&temp, &temp2, &temp3);
if (retval)
break;
if (strcasecmp(temp2, FIELD_BUS) == 0) {
strfieldcpy(dev.bus, temp3);
valid = 1;
continue;
}
if (strcasecmp(temp2, FIELD_ID) == 0) {
strfieldcpy(dev.id, temp3);
valid = 1;
continue;
}
if (strcasecmp(temp2, FIELD_PLACE) == 0) {
strfieldcpy(dev.place, temp3);
valid = 1;
continue;
}
if (strncasecmp(temp2, FIELD_SYSFS, sizeof(FIELD_SYSFS)-1) == 0) {
struct sysfs_pair *pair = &dev.sysfs_pair[0];
int sysfs_pair_num = 0;
/* find first unused pair */
while (pair->file[0] != '\0') {
++sysfs_pair_num;
if (sysfs_pair_num >= MAX_SYSFS_PAIRS) {
pair = NULL;
break;
}
++pair;
}
if (pair) {
attr = get_key_attribute(temp2 + sizeof(FIELD_SYSFS)-1);
if (attr == NULL) {
dbg("error parsing " FIELD_SYSFS " attribute");
continue;
}
strfieldcpy(pair->file, attr);
strfieldcpy(pair->value, temp3);
valid = 1;
}
continue;
}
if (strcasecmp(temp2, FIELD_KERNEL) == 0) {
strfieldcpy(dev.kernel, temp3);
valid = 1;
continue;
}
if (strcasecmp(temp2, FIELD_PROGRAM) == 0) {
program_given = 1;
strfieldcpy(dev.program, temp3);
valid = 1;
continue;
}
if (strcasecmp(temp2, FIELD_RESULT) == 0) {
strfieldcpy(dev.result, temp3);
valid = 1;
continue;
}
if (strncasecmp(temp2, FIELD_NAME, sizeof(FIELD_NAME)-1) == 0) {
attr = get_key_attribute(temp2 + sizeof(FIELD_NAME)-1);
if (attr != NULL && strcasecmp(attr, ATTR_PARTITIONS) == 0) {
dbg_parse("creation of partition nodes requested");
dev.partitions = PARTITIONS_COUNT;
}
strfieldcpy(dev.name, temp3);
valid = 1;
continue;
}
if (strcasecmp(temp2, FIELD_SYMLINK) == 0) {
strfieldcpy(dev.symlink, temp3);
valid = 1;
continue;
}
if (strcasecmp(temp2, FIELD_OWNER) == 0) {
strfieldcpy(dev.owner, temp3);
valid = 1;
continue;
}
if (strcasecmp(temp2, FIELD_GROUP) == 0) {
strfieldcpy(dev.group, temp3);
valid = 1;
continue;
}
if (strcasecmp(temp2, FIELD_MODE) == 0) {
dev.mode = strtol(temp3, NULL, 8);
valid = 1;
continue;
}
dbg("unknown type of field '%s'", temp2);
goto error;
}
/* skip line if not any valid key was found */
if (!valid)
goto error;
/* simple plausibility checks for given keys */
if ((dev.sysfs_pair[0].file[0] == '\0') ^
(dev.sysfs_pair[0].value[0] == '\0')) {
info("inconsistency in " FIELD_SYSFS " key");
goto error;
}
if ((dev.result[0] != '\0') && (program_given == 0)) {
info(FIELD_RESULT " is only useful when "
FIELD_PROGRAM " is called in any rule before");
goto error;
}
dev.config_line = lineno;
strfieldcpy(dev.config_file, filename);
retval = add_config_dev(&dev);
if (retval) {
dbg("add_config_dev returned with error %d", retval);
continue;
error:
info("parse error %s, line %d:%d, rule skipped",
filename, lineno, temp - line);
}
}
file_unmap(buf, bufsize);
return retval;
}
static int namedev_parse_permissions(char *filename)
{
char line[LINE_SIZE];
char *bufline;
char *temp;
char *temp2;
char *buf;
size_t bufsize;
size_t cur;
size_t count;
int retval = 0;
struct perm_device dev;
int lineno;
if (file_map(filename, &buf, &bufsize) == 0) {
dbg("reading '%s' as permissions file", filename);
} else {
dbg("can't open '%s' as permissions file", filename);
return -1;
}
/* loop through the whole file */
cur = 0;
lineno = 0;
while (cur < bufsize) {
count = buf_get_line(buf, bufsize, cur);
bufline = &buf[cur];
cur += count+1;
lineno++;
if (count >= LINE_SIZE) {
info("line too long, rule skipped %s, line %d",
filename, lineno);
continue;
}
/* eat the whitespace */
while ((count > 0) && isspace(bufline[0])) {
bufline++;
count--;
}
if (count == 0)
continue;
/* see if this is a comment */
if (bufline[0] == COMMENT_CHARACTER)
continue;
strncpy(line, bufline, count);
line[count] = '\0';
dbg_parse("read '%s'", line);
/* parse the line */
memset(&dev, 0x00, sizeof(struct perm_device));
temp = line;
temp2 = strsep(&temp, ":");
if (!temp2) {
dbg("cannot parse line '%s'", line);
continue;
}
strfieldcpy(dev.name, temp2);
temp2 = strsep(&temp, ":");
if (!temp2) {
dbg("cannot parse line '%s'", line);
continue;
}
strfieldcpy(dev.owner, temp2);
temp2 = strsep(&temp, ":");
if (!temp2) {
dbg("cannot parse line '%s'", line);
continue;
}
strfieldcpy(dev.group, temp2);
if (!temp) {
dbg("cannot parse line '%s'", line);
continue;
}
dev.mode = strtol(temp, NULL, 8);
dbg_parse("name='%s', owner='%s', group='%s', mode=%#o",
dev.name, dev.owner, dev.group, dev.mode);
retval = add_perm_dev(&dev);
if (retval) {
dbg("add_perm_dev returned with error %d", retval);
goto exit;
}
}
exit:
file_unmap(buf, bufsize);
return retval;
}
int namedev_init_rules()
{
struct stat stats;
stat(udev_rules_filename, &stats);
if ((stats.st_mode & S_IFMT) != S_IFDIR)
return namedev_parse_rules(udev_rules_filename);
else
return call_foreach_file(namedev_parse_rules,
udev_rules_filename, RULEFILE_SUFFIX);
}
int namedev_init_permissions()
{
struct stat stats;
stat(udev_permissions_filename, &stats);
if ((stats.st_mode & S_IFMT) != S_IFDIR)
return namedev_parse_permissions(udev_permissions_filename);
else
return call_foreach_file(namedev_parse_permissions,
udev_permissions_filename, PERMFILE_SUFFIX);
}