do not touch node ownership and permissions, if already correct

In some cases "change" events reapplied node permissions which
changed applied ACL's. So, preserve permissions if already correct.

diff --git a/udev_node.c b/udev_node.c
index 0e59e2dbc93cfaefc8249b7cf0c9aea460bd6da3..78b6747043d97b3ab7809e6ca31dd78b730c9fe6 100644 (file)
--- a/udev_node.c
+++ b/udev_node.c
@@ -39,7 +39,8 @@ int udev_node_mknod(struct udevice *udev, const char *file, dev_t devt, mode_t m
 {
        char file_tmp[PATH_SIZE + sizeof(TMP_FILE_EXT)];
        struct stat stats;
-       int retval = 0;
+       int preserve = 0;
+       int err = 0;
 
        if (major(devt) != 0 && strcmp(udev->dev->subsystem, "block") == 0)
                mode |= S_IFBLK;
@@ -47,56 +48,61 @@ int udev_node_mknod(struct udevice *udev, const char *file, dev_t devt, mode_t m
                mode |= S_IFCHR;
 
        if (lstat(file, &stats) == 0) {
-               if ((stats.st_mode & S_IFMT) == (mode & S_IFMT) && (stats.st_rdev == devt)) {
+               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;
+                       preserve = 1;
+                       selinux_setfilecon(file, udev->dev->kernel, mode);
+               } else {
+                       info("atomically replace existing file '%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);
+                       err = mknod(file_tmp, mode, devt);
+                       selinux_resetfscreatecon();
+                       if (err != 0) {
+                               err("mknod(%s, %#o, %u, %u) failed: %s\n",
+                                   file_tmp, mode, major(devt), minor(devt), strerror(errno));
+                               goto exit;
+                       }
+                       err = rename(file_tmp, file);
+                       if (err != 0) {
+                               err("rename(%s, %s) failed: %s\n",
+                                   file_tmp, file, strerror(errno));
+                               unlink(file_tmp);
+                       }
                }
        } else {
+               info("mknod(%s, %#o, (%u,%u))\n", file, mode, major(devt), minor(devt));
                selinux_setfscreatecon(file, udev->dev->kernel, mode);
-               retval = mknod(file, mode, devt);
+               err = mknod(file, mode, devt);
                selinux_resetfscreatecon();
-               if (retval == 0)
-                       goto perms;
-       }
-
-       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\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;
+               if (err != 0) {
+                       err("mknod(%s, %#o, (%u,%u) failed: %s\n",
+                           file, mode, major(devt), minor(devt), strerror(errno));
+                       goto exit;
+               }
        }
 
-perms:
-       dbg("chmod(%s, %#o)\n", file, mode);
-       if (chmod(file, mode) != 0) {
-               err("chmod(%s, %#o) failed: %s\n", file, mode, strerror(errno));
-               goto exit;
+       if (!preserve || stats.st_mode != mode) {
+               info("chmod(%s, %#o)\n", file, mode);
+               err = chmod(file, mode);
+               if (err != 0) {
+                       err("chmod(%s, %#o) failed: %s\n", file, mode, strerror(errno));
+                       goto exit;
+               }
        }
 
-       if (uid != 0 || gid != 0) {
-               dbg("chown(%s, %u, %u)\n", file, uid, gid);
-               if (chown(file, uid, gid) != 0) {
-                       err("chown(%s, %u, %u) failed: %s\n",
-                           file, uid, gid, strerror(errno));
+       if (!preserve || stats.st_uid != uid || stats.st_gid != gid) {
+               info("chown(%s, %u, %u)\n", file, uid, gid);
+               err = chown(file, uid, gid);
+               if (err != 0) {
+                       err("chown(%s, %u, %u) failed: %s\n", file, uid, gid, strerror(errno));
                        goto exit;
                }
        }
 exit:
-       return retval;
+       return err;
 }
 
 static int node_symlink(const char *node, const char *slink)