From: Arnd Bergmann <arnd@arndb.de>
To: linux-hotplug@vger.kernel.org
Subject: [PATCH] more robust config file parsing in udev/devnaming.c
Date: Tue, 18 Nov 2003 17:29:25 +0000 [thread overview]
Message-ID: <marc-linux-hotplug-106917668928469@msgid-missing> (raw)
After getting a number of different crashes for udev reading broken
udev.config files, I decided to try to make the parser a little
more robust.
The behaviour is changed to stop reading the configuration file
and logging the broken entry instead of silently ignoring it (is
that good? It's easy to just print and continue).
All strcpy()'s to a fixed length string are now implicitly limited
to the bounds of the target string.
I kept the -ENODEV return code for now, not sure if there should be
different ones.
Arnd <><
=== namedev.c 1.32 vs edited ==--- 1.32/namedev.c Tue Nov 18 02:22:01 2003
+++ edited/namedev.c Tue Nov 18 17:41:44 2003
@@ -144,37 +144,15 @@
dump_dev(dev);
}
}
-
-static int get_value(const char *left, char **orig_string, char **ret_string)
-{
- char *temp;
- char *string = *orig_string;
-
- /* eat any whitespace */
- while (isspace(*string))
- ++string;
-
- /* split based on '=' */
- temp = strsep(&string, "=");
- if (strcasecmp(temp, left) = 0) {
- /* got it, now strip off the '"' */
- while (isspace(*string))
- ++string;
- if (*string = '"')
- ++string;
- temp = strsep(&string, "\"");
- *ret_string = temp;
- *orig_string = string;
- return 0;
- }
- return -ENODEV;
-}
static int get_pair(char **orig_string, char **left, char **right)
{
char *temp;
char *string = *orig_string;
+ if (!string)
+ return -ENODEV;
+
/* eat any whitespace */
while (isspace(*string))
++string;
@@ -182,22 +160,43 @@
/* split based on '=' */
temp = strsep(&string, "=");
*left = temp;
+ if (!string)
+ return -ENODEV;
/* take the right side and strip off the '"' */
while (isspace(*string))
++string;
if (*string = '"')
++string;
+ else
+ return -ENODEV;
+
temp = strsep(&string, "\"");
+ if (!string || *temp = '\0')
+ return -ENODEV;
*right = temp;
*orig_string = string;
return 0;
}
+static int get_value(const char *left, char **orig_string, char **ret_string)
+{
+ int retval;
+ char *left_string;
+
+ retval = get_pair(orig_string, &left_string, ret_string);
+ if (retval)
+ return retval;
+ if (strcasecmp(left_string, left) != 0)
+ return -ENODEV;
+ return 0;
+}
+
static int namedev_init_config(void)
{
char line[255];
+ int lineno;
char *temp;
char *temp2;
char *temp3;
@@ -213,11 +212,13 @@
}
/* loop through the whole file */
+ lineno = 0;
while (1) {
/* get a line */
temp = fgets(line, sizeof(line), fd);
if (temp = NULL)
- break;
+ goto exit;
+ lineno++;
dbg_parse("read %s", temp);
@@ -244,23 +245,23 @@
/* BUS="bus" */
retval = get_value("BUS", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.bus, temp3);
+ break;
+ strfieldcpy(dev.bus, temp3);
/* file="value" */
temp2 = strsep(&temp, ",");
retval = get_pair(&temp, &temp2, &temp3);
if (retval)
- continue;
- strcpy(dev.sysfs_file, temp2);
- strcpy(dev.sysfs_value, temp3);
+ break;
+ strfieldcpy(dev.sysfs_file, temp2);
+ strfieldcpy(dev.sysfs_value, temp3);
/* NAME="new_name" */
temp2 = strsep(&temp, ",");
retval = get_value("NAME", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.name, temp3);
+ break;
+ strfieldcpy(dev.name, temp3);
dbg_parse("LABEL name = '%s', bus = '%s', "
"sysfs_file = '%s', sysfs_value = '%s'",
@@ -275,22 +276,22 @@
/* BUS="bus" */
retval = get_value("BUS", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.bus, temp3);
+ break;
+ strfieldcpy(dev.bus, temp3);
/* ID="id" */
temp2 = strsep(&temp, ",");
retval = get_value("id", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.id, temp3);
+ break;
+ strfieldcpy(dev.id, temp3);
/* NAME="new_name" */
temp2 = strsep(&temp, ",");
retval = get_value("NAME", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.name, temp3);
+ break;
+ strfieldcpy(dev.name, temp3);
dbg_parse("NUMBER name = '%s', bus = '%s', id = '%s'",
dev.name, dev.bus, dev.id);
@@ -303,22 +304,22 @@
/* BUS="bus" */
retval = get_value("BUS", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.bus, temp3);
+ break;
+ strfieldcpy(dev.bus, temp3);
/* PLACE="place" */
temp2 = strsep(&temp, ",");
retval = get_value("place", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.place, temp3);
+ break;
+ strfieldcpy(dev.place, temp3);
/* NAME="new_name" */
temp2 = strsep(&temp, ",");
retval = get_value("NAME", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.name, temp3);
+ break;
+ strfieldcpy(dev.name, temp3);
dbg_parse("TOPOLOGY name = '%s', bus = '%s', place = '%s'",
dev.name, dev.bus, dev.place);
@@ -331,15 +332,15 @@
/* KERNEL="kernel_name" */
retval = get_value("KERNEL", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.kernel_name, temp3);
+ break;
+ strfieldcpy(dev.kernel_name, temp3);
/* NAME="new_name" */
temp2 = strsep(&temp, ",");
retval = get_value("NAME", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.name, temp3);
+ break;
+ strfieldcpy(dev.name, temp3);
dbg_parse("REPLACE name = %s, kernel_name = %s",
dev.name, dev.kernel_name);
}
@@ -350,29 +351,29 @@
/* PROGRAM="executable" */
retval = get_value("PROGRAM", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.exec_program, temp3);
+ break;
+ strfieldcpy(dev.exec_program, temp3);
/* BUS="bus" */
temp2 = strsep(&temp, ",");
retval = get_value("BUS", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.bus, temp3);
+ break;
+ strfieldcpy(dev.bus, temp3);
/* ID="id" */
temp2 = strsep(&temp, ",");
retval = get_value("ID", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.id, temp3);
+ break;
+ strfieldcpy(dev.id, temp3);
/* NAME="new_name" */
temp2 = strsep(&temp, ",");
retval = get_value("NAME", &temp, &temp3);
if (retval)
- continue;
- strcpy(dev.name, temp3);
+ break;
+ strfieldcpy(dev.name, temp3);
dbg_parse("CALLOUT name = %s, program = %s",
dev.name, dev.exec_program);
}
@@ -383,7 +384,8 @@
goto exit;
}
}
-
+ dbg_parse("%s:%d:%Zd: error parsing ``%s''", udev_config_filename,
+ lineno, temp - line, temp);
exit:
fclose(fd);
return retval;
@@ -552,11 +554,11 @@
continue;
if (strncmp(value, dev->id, sizeof(value)) != 0)
continue;
- strcpy(udev->name, dev->name);
+ strfieldcpy(udev->name, dev->name);
if (dev->mode != 0) {
udev->mode = dev->mode;
- strcpy(udev->owner, dev->owner);
- strcpy(udev->group, dev->group);
+ strfieldcpy(udev->owner, dev->owner);
+ strfieldcpy(udev->group, dev->group);
}
dbg_parse("device callout '%s' becomes '%s' - owner = %s, group = %s, mode = %#o",
dev->id, udev->name,
@@ -571,7 +573,6 @@
struct sysfs_attribute *tmpattr = NULL;
struct config_device *dev;
struct list_head *tmp;
- char *temp = NULL;
list_for_each(tmp, &config_device_list) {
dev = list_entry(tmp, struct config_device, node);
@@ -600,11 +601,11 @@
if (strcmp(dev->sysfs_value, tmpattr->value) != 0)
continue;
- strcpy(udev->name, dev->name);
+ strfieldcpy(udev->name, dev->name);
if (dev->mode != 0) {
udev->mode = dev->mode;
- strcpy(udev->owner, dev->owner);
- strcpy(udev->group, dev->group);
+ strfieldcpy(udev->owner, dev->owner);
+ strfieldcpy(udev->group, dev->group);
}
dbg_parse("file '%s' with value '%s' becomes '%s' - owner = %s, group = %s, mode = %#o",
dev->sysfs_file, dev->sysfs_value, udev->name,
@@ -633,7 +634,7 @@
continue;
found = 0;
- strcpy(path, sysfs_device->path);
+ strfieldcpy(path, sysfs_device->path);
temp = strrchr(path, '/');
dbg_parse("NUMBER path = '%s'", path);
dbg_parse("NUMBER temp = '%s' id = '%s'", temp, dev->id);
@@ -648,11 +649,11 @@
}
if (!found)
continue;
- strcpy(udev->name, dev->name);
+ strfieldcpy(udev->name, dev->name);
if (dev->mode != 0) {
udev->mode = dev->mode;
- strcpy(udev->owner, dev->owner);
- strcpy(udev->group, dev->group);
+ strfieldcpy(udev->owner, dev->owner);
+ strfieldcpy(udev->group, dev->group);
}
dbg_parse("device id '%s' becomes '%s' - owner = %s, group = %s, mode = %#o",
dev->id, udev->name,
@@ -681,7 +682,7 @@
continue;
found = 0;
- strcpy(path, sysfs_device->path);
+ strfieldcpy(path, sysfs_device->path);
temp = strrchr(path, '/');
dbg_parse("TOPOLOGY path = '%s'", path);
dbg_parse("TOPOLOGY temp = '%s' place = '%s'", temp, dev->place);
@@ -697,11 +698,11 @@
if (!found)
continue;
- strcpy(udev->name, dev->name);
+ strfieldcpy(udev->name, dev->name);
if (dev->mode != 0) {
udev->mode = dev->mode;
- strcpy(udev->owner, dev->owner);
- strcpy(udev->group, dev->group);
+ strfieldcpy(udev->owner, dev->owner);
+ strfieldcpy(udev->group, dev->group);
}
dbg_parse("device at '%s' becomes '%s' - owner = %s, group = %s, mode = %#o",
dev->place, udev->name,
@@ -727,11 +728,11 @@
if (strcmp(dev->kernel_name, class_dev->name) != 0)
continue;
- strcpy(udev->name, dev->name);
+ strfieldcpy(udev->name, dev->name);
if (dev->mode != 0) {
udev->mode = dev->mode;
- strcpy(udev->owner, dev->owner);
- strcpy(udev->group, dev->group);
+ strfieldcpy(udev->owner, dev->owner);
+ strfieldcpy(udev->group, dev->group);
}
dbg_parse("'%s' becomes '%s' - owner = %s, group = %s, mode = %#o",
dev->kernel_name, udev->name,
@@ -766,7 +767,7 @@
char path[SYSFS_PATH_MAX];
dbg_parse("really is a partition...");
- strcpy(path, class_dev->path);
+ strfieldcpy(path, class_dev->path);
temp = strrchr(path, '/');
*temp = 0x00;
dbg_parse("looking for a class device at '%s'", path);
@@ -810,7 +811,7 @@
if (retval = 0)
goto done;
- strcpy(udev->name, class_dev->name);
+ strfieldcpy(udev->name, class_dev->name);
done:
/* substitute placeholder in NAME */
@@ -819,7 +820,7 @@
char *dig;
char name[NAME_SIZE];
if (pos) {
- strcpy(name, pos+2);
+ strfieldcpy(name, pos+2);
*pos = 0x00;
switch (pos[1]) {
case 'n':
=== udev.h 1.18 vs edited ==--- 1.18/udev.h Tue Oct 21 23:28:31 2003
+++ edited/udev.h Tue Nov 18 17:41:44 2003
@@ -69,6 +69,12 @@
int minor;
mode_t mode;
};
+
+#define strfieldcpy(to, from) \
+do { \
+ to[sizeof(to)-1] = '\0'; \
+ strncpy(to, from, sizeof(to)-1); \
+} while (0)
extern int udev_add_device(char *path, char *subsystem);
extern int udev_remove_device(char *path, char *subsystem);
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next reply other threads:[~2003-11-18 17:29 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-11-18 17:29 Arnd Bergmann [this message]
2003-11-19 0:23 ` [PATCH] more robust config file parsing in udev/devnaming.c Greg KH
2003-11-19 0:23 ` Greg KH
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