--from-json allows reading from device files using a significant amount of memory

[armijnhemel]

Description

Related to #3588, #3589, #3590, #3591, #3592

--from-json allows reading from device files such as /dev/zero causing scancode to use quite a bit of memory.

How To Reproduce

$ ./scancode --from-json /dev/zero --yaml /tmp/scancode.yaml
Setup plugins...
Collect file inventory...
Terminated

System configuration

For bug reports, it really helps us to know:

• What OS are you running on? (Windows/MacOS/Linux)
• What version of scancode-toolkit was used to generate the scan file?
• What installation method was used to install/run scancode? (pip/source download/other)

[pombredanne]

Closed in favor of #3596

[armijnhemel]

Verified that this is no longer happening.