_ChunkedTransferDecoder may buffer an arbitrary amount

[twisted-trac]

	@twm reported
Trac ID	trac#10144
Type	defect
Created	2021-03-19 06:16:46Z
Branch	https://github.com/twisted/twisted/tree/10144-chunkedtransferdecoder-buffering

The decoder may buffer an arbitrary amount of memory while waiting for a CRLF sequence in several places:

1. When waiting for the end of the length and extensions line.
2. When waiting for a terminating CRLF after data
3. When waiting for a terminating CRLF after an empty chunk

In case (1) the length of the line should be limited to a reasonable amount (say, 4 KiB).

Cases (2) and (3) are covered by #10137.

This is a follow-up to #3795

Searchable metadata

trac-id__10144 10144
type__defect defect
reporter__twm twm
priority__normal normal
milestone__None None
branch__10144_chunkedtransferdecoder_buffering 10144-chunkedtransferdecoder-buffering
branch_author__ 
status__closed closed
resolution__fixed fixed
component__web web
keywords__review review
time__1616134606247167 1616134606247167
changetime__1617087660218906 1617087660218906
version__None None
owner__Tom_Most__twm_____ Tom Most <twm@...>

[twisted-trac]

	@twm set owner to @twm @twm set status to assigned

Draft PR: #1563

[twisted-trac]

	@twm removed owner @twm set status to new

[twisted-trac]

	@twm set owner to @twm @twm set status to closed

In changeset a360a8a

#!CommitTicketReference repository="" revision="a360a8a18a73b6dc18412549a6ecad52be9fc5fa"
Merge pull request #1563 from twisted/10144-chunkedtransferdecoder-buffering

Author: twm
Reviewer: adiroiban
Fixes: ticket:10144

Limit ChunkedTransferDecoder buffering