coreutils version 9.1-1 on Debian testing, but also exists in previous
versions.
Example:
stat -f /dev/sdb
File: "/dev/sdb"
ID: eb91af7d7bda02dd Namelen: 255 Type: tmpfs
Block size: 4096 Fundamental block size: 4096
Blocks: Total: 2012292 Free: 2012292 Available: 2012292
Inodes: Total: 2012292 Free: 2011839
stat -f /dev/disk/by-uuid/6abaa68a-2670-4d8b-8d2a-fd7321df9242
File: "/dev/disk/by-uuid/6abaa68a-2670-4d8b-8d2a-fd7321df9242"
ID: eb91af7d7bda02dd Namelen: 255 Type: tmpfs
Block size: 4096 Fundamental block size: 4096
Blocks: Total: 2012292 Free: 2012292 Available: 2012292
Inodes: Total: 2012292 Free: 2011839
blkid /dev/sdb
/dev/sdb: UUID="6abaa68a-2670-4d8b-8d2a-fd7321df9242"
UUID_SUB="d15f1846-8f18-4ba0-9e2a-a6aaa7bbf83b" BLOCK_SIZE="4096"
TYPE="btrfs"
Not sure why the reported fstype is wrong but obviously it is a bug.
TIA