Decrease buffer size when advancing past NUL byte

[elogind.git] / libudev / libudev-device.c

diff --git a/libudev/libudev-device.c b/libudev/libudev-device.c
index add1c99ec03bcb89ded7c05c6a8c782d572874b0..4f42aa2810795af231bc7e0ccf28b08ec5739e72 100644 (file)
--- a/libudev/libudev-device.c
+++ b/libudev/libudev-device.c
@@ -303,25 +303,7 @@ struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *
        util_strscpy(path, sizeof(path), syspath);
        util_resolve_sys_link(udev, path, sizeof(path));
 
-       /* try to resolve the silly block layout if needed */
-       if (strncmp(&path[len], "/block/", 7) == 0) {
-               char block[UTIL_PATH_SIZE];
-               char part[UTIL_PATH_SIZE];
-
-               util_strscpy(block, sizeof(block), path);
-               pos = strrchr(block, '/');
-               if (pos == NULL)
-                       return NULL;
-               util_strscpy(part, sizeof(part), pos);
-               pos[0] = '\0';
-               if (util_resolve_sys_link(udev, block, sizeof(block)) == 0)
-                       util_strscpyl(path, sizeof(path), block, part, NULL);
-       }
-
-       /* path exists in sys */
-       if (strncmp(&syspath[len], "/devices/", 9) == 0 ||
-           strncmp(&syspath[len], "/class/", 7) == 0 ||
-           strncmp(&syspath[len], "/block/", 7) == 0) {
+       if (strncmp(&syspath[len], "/devices/", 9) == 0) {
                char file[UTIL_PATH_SIZE];
 
                /* all "devices" require a "uevent" file */
@@ -369,9 +351,6 @@ struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, de
 {
        char path[UTIL_PATH_SIZE];
        const char *type_str;
-       struct udev_enumerate *udev_enumerate;
-       struct udev_list_entry *list_entry;
-       struct udev_device *device = NULL;
 
        if (type == 'b')
                type_str = "block";
@@ -380,40 +359,10 @@ struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, de
        else
                return NULL;
 
-       /* /sys/dev/{block,char}/<maj>:<min> link */
-       snprintf(path, sizeof(path), "%s/dev/%s/%u:%u", udev_get_sys_path(udev),
-                type_str, major(devnum), minor(devnum));
-       if (util_resolve_sys_link(udev, path, sizeof(path)) == 0)
-               return udev_device_new_from_syspath(udev, path);
-
-       udev_enumerate = udev_enumerate_new(udev);
-       if (udev_enumerate == NULL)
-               return NULL;
-
-       /* fallback to search sys devices for the major/minor */
-       if (type == 'b')
-               udev_enumerate_add_match_subsystem(udev_enumerate, "block");
-       else if (type == 'c')
-               udev_enumerate_add_nomatch_subsystem(udev_enumerate, "block");
-       udev_enumerate_scan_devices(udev_enumerate);
-       udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
-               struct udev_device *device_loop;
-
-               device_loop = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
-               if (device_loop != NULL) {
-                       if (udev_device_get_devnum(device_loop) == devnum) {
-                               if (type == 'b' && strcmp(udev_device_get_subsystem(device_loop), "block") != 0)
-                                       continue;
-                               if (type == 'c' && strcmp(udev_device_get_subsystem(device_loop), "block") == 0)
-                                       continue;
-                               device = device_loop;
-                               break;
-                       }
-                       udev_device_unref(device_loop);
-               }
-       }
-       udev_enumerate_unref(udev_enumerate);
-       return device;
+       /* use /sys/dev/{block,char}/<maj>:<min> link */
+       snprintf(path, sizeof(path), "%s/dev/%s/%u:%u",
+                udev_get_sys_path(udev), type_str, major(devnum), minor(devnum));
+       return udev_device_new_from_syspath(udev, path);
 }
 
 /**
@@ -508,20 +457,9 @@ static struct udev_device *device_new_from_parent(struct udev_device *udev_devic
        char path[UTIL_PATH_SIZE];
        const char *subdir;
 
-       /* follow "device" link in deprecated sys layout */
-       if (strncmp(udev_device->devpath, "/class/", 7) == 0 ||
-           strncmp(udev_device->devpath, "/block/", 7) == 0) {
-               util_strscpyl(path, sizeof(path), udev_device->syspath, "/device", NULL);
-               if (util_resolve_sys_link(udev_device->udev, path, sizeof(path)) == 0) {
-                       udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
-                       if (udev_device_parent != NULL)
-                               return udev_device_parent;
-               }
-       }
-
        util_strscpy(path, sizeof(path), udev_device->syspath);
        subdir = &path[strlen(udev_get_sys_path(udev_device->udev))+1];
-       while (1) {
+       for (;;) {
                char *pos;
 
                pos = strrchr(subdir, '/');
@@ -1228,7 +1166,9 @@ static int update_envp_monitor_buf(struct udev_device *udev_device)
                l = util_strpcpyl(&s, l, key, "=", udev_list_entry_get_value(list_entry), NULL);
                if (l == 0)
                        return -EINVAL;
+               /* advance past the trailing '\0' that util_strpcpyl() guarantees */
                s++;
+               l--;
        }
        udev_device->envp[i] = NULL;
        udev_device->monitor_buf_len = s - udev_device->monitor_buf;