setuid and setgid shell scripts use the file descriptors in /dev/fd. The contents of /dev/fd are a file descriptor file system (FDFS) and have no connection with floppy disks!
Ensure that the fdfs is mounted as /dev/fd. Before the machine is next rebooted, the following line should appear in /etc/vfstab, exactly like this (with no initial comment symbol):
fd - /dev/fd fd - no -
It might be possible to remount /dev/fd without rebooting by running the following as root:
# mount fd /dev/fd
Some administrators, unaware of what /dev/fd is for, comment out the entry in /etc/vfstab that mounts the FDFS (file descriptor file system). This can go unnoticed until an attempt is made to run a setuid or setgid shell script.