#include "udev_rules.h"
#include "udev_selinux.h"
+#define TMP_FILE_EXT ".udev-tmp"
int udev_node_mknod(struct udevice *udev, const char *file, dev_t devt, mode_t mode, uid_t uid, gid_t gid)
{
+ char file_tmp[PATH_SIZE + sizeof(TMP_FILE_EXT)];
struct stat stats;
int retval = 0;
else
mode |= S_IFCHR;
- if (lstat(file, &stats) != 0)
- goto create;
-
- /* preserve node with already correct numbers, to prevent changing the inode number */
- if ((stats.st_mode & S_IFMT) == (mode & S_IFMT) && (stats.st_rdev == devt)) {
- info("preserve file '%s', because it has correct dev_t", file);
- selinux_setfilecon(file, udev->dev->kernel, stats.st_mode);
- goto perms;
+ if (lstat(file, &stats) == 0) {
+ if ((stats.st_mode & S_IFMT) == (mode & S_IFMT) && (stats.st_rdev == devt)) {
+ info("preserve file '%s', because it has correct dev_t\n", file);
+ selinux_setfilecon(file, udev->dev->kernel, stats.st_mode);
+ goto perms;
+ }
+ } else {
+ selinux_setfscreatecon(file, udev->dev->kernel, mode);
+ retval = mknod(file, mode, devt);
+ selinux_resetfscreatecon();
+ if (retval == 0)
+ goto perms;
}
- if (unlink(file) != 0)
- err("unlink(%s) failed: %s", file, strerror(errno));
- else
- dbg("already present file '%s' unlinked", file);
-
-create:
- selinux_setfscreatecon(file, udev->dev->kernel, mode);
- retval = mknod(file, mode, devt);
+ info("atomically replace '%s'\n", file);
+ strlcpy(file_tmp, file, sizeof(file_tmp));
+ strlcat(file_tmp, TMP_FILE_EXT, sizeof(file_tmp));
+ unlink(file_tmp);
+ selinux_setfscreatecon(file_tmp, udev->dev->kernel, mode);
+ retval = mknod(file_tmp, mode, devt);
selinux_resetfscreatecon();
if (retval != 0) {
- err("mknod(%s, %#o, %u, %u) failed: %s",
- file, mode, major(devt), minor(devt), strerror(errno));
+ err("mknod(%s, %#o, %u, %u) failed: %s\n",
+ file_tmp, mode, major(devt), minor(devt), strerror(errno));
+ goto exit;
+ }
+ retval = rename(file_tmp, file);
+ if (retval != 0) {
+ err("rename(%s, %s) failed: %s\n",
+ file_tmp, file, strerror(errno));
+ unlink(file_tmp);
goto exit;
}
perms:
- dbg("chmod(%s, %#o)", file, mode);
+ dbg("chmod(%s, %#o)\n", file, mode);
if (chmod(file, mode) != 0) {
- err("chmod(%s, %#o) failed: %s", file, mode, strerror(errno));
+ err("chmod(%s, %#o) failed: %s\n", file, mode, strerror(errno));
goto exit;
}
if (uid != 0 || gid != 0) {
- dbg("chown(%s, %u, %u)", file, uid, gid);
+ dbg("chown(%s, %u, %u)\n", file, uid, gid);
if (chown(file, uid, gid) != 0) {
- err("chown(%s, %u, %u) failed: %s",
+ err("chown(%s, %u, %u) failed: %s\n",
file, uid, gid, strerror(errno));
goto exit;
}
}
-
exit:
return retval;
}
static int node_symlink(const char *node, const char *slink)
{
+ struct stat stats;
char target[PATH_SIZE] = "";
- char buf[PATH_SIZE];
+ char slink_tmp[PATH_SIZE + sizeof(TMP_FILE_EXT)];
int i = 0;
int tail = 0;
int len;
+ int retval = 0;
/* use relative link */
while (node[i] && (node[i] == slink[i])) {
}
strlcat(target, &node[tail], sizeof(target));
- /* look if symlink already exists */
- len = readlink(slink, buf, sizeof(buf));
- if (len > 0) {
- buf[len] = '\0';
- if (strcmp(target, buf) == 0) {
- info("preserve already existing symlink '%s' to '%s'", slink, target);
- selinux_setfilecon(slink, NULL, S_IFLNK);
- goto exit;
+ /* preserve link with correct target, do not replace node of other device */
+ if (lstat(slink, &stats) == 0) {
+ if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
+ struct stat stats2;
+
+ info("found existing node instead of symlink '%s'\n", slink);
+ if (lstat(node, &stats2) == 0) {
+ if ((stats.st_mode & S_IFMT) == (stats2.st_mode & S_IFMT) &&
+ stats.st_rdev == stats2.st_rdev) {
+ info("replace device node '%s' with symlink to our node '%s'\n", slink, node);
+ } else {
+ err("device node '%s' already exists, link to '%s' will not overwrite it\n", slink, node);
+ goto exit;
+ }
+ }
+ } else if (S_ISLNK(stats.st_mode)) {
+ char buf[PATH_SIZE];
+
+ info("found existing symlink '%s'\n", slink);
+ len = readlink(slink, buf, sizeof(buf));
+ if (len > 0) {
+ buf[len] = '\0';
+ if (strcmp(target, buf) == 0) {
+ info("preserve already existing symlink '%s' to '%s'\n", slink, target);
+ selinux_setfilecon(slink, NULL, S_IFLNK);
+ goto exit;
+ }
+ }
}
- info("link '%s' points to different target '%s', delete it", slink, buf);
- unlink(slink);
+ } else {
+ info("creating symlink '%s' to '%s'\n", slink, target);
+ selinux_setfscreatecon(slink, NULL, S_IFLNK);
+ retval = symlink(target, slink);
+ selinux_resetfscreatecon();
+ if (retval == 0)
+ goto exit;
}
- /* create link */
- info("creating symlink '%s' to '%s'", slink, target);
+ info("atomically replace '%s'\n", slink);
+ strlcpy(slink_tmp, slink, sizeof(slink_tmp));
+ strlcat(slink_tmp, TMP_FILE_EXT, sizeof(slink_tmp));
+ unlink(slink_tmp);
selinux_setfscreatecon(slink, NULL, S_IFLNK);
- if (symlink(target, slink) != 0)
- err("symlink(%s, %s) failed: %s", target, slink, strerror(errno));
+ retval = symlink(target, slink_tmp);
selinux_resetfscreatecon();
-
+ if (retval != 0) {
+ err("symlink(%s, %s) failed: %s\n", target, slink_tmp, strerror(errno));
+ goto exit;
+ }
+ retval = rename(slink_tmp, slink);
+ if (retval != 0) {
+ err("rename(%s, %s) failed: %s\n", slink_tmp, slink, strerror(errno));
+ unlink(slink_tmp);
+ goto exit;
+ }
exit:
- return 0;
+ return retval;
}
static int update_link(struct udevice *udev, const char *name)
strlcat(slink, name, sizeof(slink));
count = udev_db_get_devices_by_name(name, &name_list);
- info("found %i devices with name '%s'", count, name);
+ info("found %i devices with name '%s'\n", count, name);
/* if we don't have a reference, delete it */
if (count <= 0) {
- info("no reference left, remove '%s'", name);
+ info("no reference left, remove '%s'\n", name);
if (!udev->test_run) {
unlink(slink);
delete_path(slink);
/* find the device with the highest priority */
list_for_each_entry(device, &name_list, node) {
- info("found '%s' for '%s'", device->name, name);
+ info("found '%s' for '%s'\n", device->name, name);
/* did we find ourself? we win, if we have the same priority */
if (strcmp(udev->dev->devpath, device->name) == 0) {
- info("compare (our own) priority of '%s' %i >= %i",
+ info("compare (our own) priority of '%s' %i >= %i\n",
udev->dev->devpath, udev->link_priority, priority);
- if (target[0] == '\0' || udev->link_priority >= priority) {
+ if (strcmp(udev->name, name) == 0) {
+ info("'%s' is our device node, database inconsistent, skip link update\n", udev->name);
+ } else if (target[0] == '\0' || udev->link_priority >= priority) {
priority = udev->link_priority;
strlcpy(target, udev->name, sizeof(target));
}
continue;
}
- /* or something else, then read priority from database */
+ /* another device, read priority from database */
udev_db = udev_device_init(NULL);
if (udev_db == NULL)
continue;
if (udev_db_get_device(udev_db, device->name) == 0) {
- info("compare priority of '%s' %i > %i",
- udev_db->dev->devpath, udev_db->link_priority, priority);
- if (target[0] == '\0' || udev_db->link_priority > priority) {
- priority = udev_db->link_priority;
- strlcpy(target, udev_db->name, sizeof(target));
+ if (strcmp(udev_db->name, name) == 0) {
+ info("'%s' is a device node of '%s', skip link update\n", udev_db->name, device->name);
+ } else {
+ info("compare priority of '%s' %i > %i\n",
+ udev_db->dev->devpath, udev_db->link_priority, priority);
+ if (target[0] == '\0' || udev_db->link_priority > priority) {
+ priority = udev_db->link_priority;
+ strlcpy(target, udev_db->name, sizeof(target));
+ }
}
}
udev_device_cleanup(udev_db);
name_list_cleanup(&name_list);
if (target[0] == '\0') {
- err("missing target for '%s'", name);
- rc = -1;
+ info("no current target for '%s' found\n", name);
+ rc = 1;
goto out;
}
strlcpy(node, udev_root, sizeof(node));
strlcat(node, "/", sizeof(node));
strlcat(node, target, sizeof(node));
- info("'%s' with target '%s' has the highest priority %i, create it", name, target, priority);
+ info("'%s' with target '%s' has the highest priority %i, create it\n", name, target, priority);
if (!udev->test_run) {
create_path(slink);
node_symlink(node, slink);
char symlinks[PATH_SIZE] = "";
list_for_each_entry(name_loop, &udev->symlink_list, node) {
- info("update symlink '%s' of '%s'", name_loop->name, udev->dev->devpath);
+ info("update symlink '%s' of '%s'\n", name_loop->name, udev->dev->devpath);
update_link(udev, name_loop->name);
strlcat(symlinks, udev_root, sizeof(symlinks));
strlcat(symlinks, "/", sizeof(symlinks));
}
if (!found) {
/* link does no longer belong to this device */
- info("update old symlink '%s' no longer belonging to '%s'",
+ info("update old symlink '%s' no longer belonging to '%s'\n",
link_old_loop->name, udev->dev->devpath);
update_link(udev, link_old_loop->name);
}
gid = lookup_group(udev->group);
}
- info("creating device node '%s', major = '%d', minor = '%d', " "mode = '%#o', uid = '%d', gid = '%d'",
+ info("creating device node '%s', major=%d, minor=%d, mode=%#o, uid=%d, gid=%d\n",
filename, major(udev->devt), minor(udev->devt), udev->mode, uid, gid);
if (!udev->test_run)
if (range > 1)
udev->partitions = range-1;
}
- info("creating device partition nodes '%s[1-%i]'", filename, udev->partitions);
+ info("creating device partition nodes '%s[1-%i]'\n", filename, udev->partitions);
if (!udev->test_run) {
for (i = 1; i <= udev->partitions; i++) {
dev_t part_devt;
strlcat(filename, "/", sizeof(filename));
strlcat(filename, udev->name, sizeof(filename));
if (stat(filename, &stats) != 0) {
- dbg("device node '%s' not found", filename);
- return -1;
+ info("device node '%s' not found\n", filename);
+ return 0;
}
if (udev->devt && stats.st_rdev != udev->devt) {
- info("device node '%s' points to a different device, skip removal", filename);
+ info("device node '%s' points to a different device, skip removal\n", filename);
return -1;
}
- info("removing device node '%s'", filename);
+ info("removing device node '%s'\n", filename);
if (!udev->test_run)
retval = unlink_secure(filename);
if (retval)
if (num > 0) {
int i;
- info("removing all_partitions '%s[1-%i]'", filename, num);
+ info("removing all_partitions '%s[1-%i]'\n", filename, num);
if (num > 255)
return -1;
for (i = 1; i <= num; i++) {
~ianmdlvl / elogind.git / blobdiff