1 diff --git a/mkfs.ubifs/mkfs.ubifs.c b/mkfs.ubifs/mkfs.ubifs.c
2 index f77e5e6..e002be5 100644
3 --- a/mkfs.ubifs/mkfs.ubifs.c
4 +++ b/mkfs.ubifs/mkfs.ubifs.c
5 @@ -324,6 +324,22 @@ static int in_path(const char *dir_name, const char *file_name)
10 + * same_device - determine if a file is on the same blockdevice as a directory.
11 + * @dir_name: directory path name
12 + * @file_name: file path name
14 +static int same_device(const char *dir_name, const char *file_name)
16 + struct stat stat1, stat2;
18 + if (stat(dir_name, &stat1) == -1)
20 + if (stat(file_name, &stat2) == -1)
22 + return stat1.st_dev == stat2.st_dev;
26 * calc_min_log_lebs - calculate the minimum number of log LEBs needed.
27 * @max_bud_bytes: journal size (buds only)
28 @@ -376,7 +392,7 @@ static int validate_options(void)
31 return err_msg("no output file or UBI volume specified");
32 - if (root && in_path(root, output))
33 + if (root && same_device(root, output) && in_path(root, output))
34 return err_msg("output file cannot be in the UBIFS root "
36 if (!is_power_of_2(c->min_io_size))