Make dmesg parsing non-UTF-tolerant #78
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
When Python's bytes.decode() method encounters encounters a byte sequence that cannot be decoded, it will take an action dependent on its second argument: 'strict': raise UnicodeDecodeError exception (default) 'replace': insert U+FFFD 'ignore': skip to next character While most inputs appear to be sanitized, dmesg output is passed to _parse_dmesg() as is, and can contain data that escapes to invalid Unicode. When the parser attempts to decode this data it immediately raises an exception and dies, as seen in xrmx#77. To prevent this issue, I set the error handling method to 'replace', as 'ignore' can hide decoding errors from developers working with *really* broken dmesg logs. The parts of dmesg the parser looks at should be in a standard format anyway, so a U+FFFD (Replacement Character) or two after the timestamp shouldn't be too harmful.
|
Thanks! |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
When Python's bytes.decode() method encounters encounters a byte sequence
that cannot be decoded, it will take an action dependent on its second argument:
'strict': raise UnicodeDecodeError exception (default)
'replace': insert U+FFFD
'ignore': skip to next character
While most inputs appear to be (mostly) sanitized, dmesg output is passed to
_parse_dmesg() as is, and can contain data that escapes to invalid Unicode.
When the parser attempts to decode this data it immediately raises an exception
and dies, as seen in #77.
To prevent this issue, I set the error handling method to 'replace', as 'ignore' can
hide decoding errors from developers working with really broken dmesg logs.
The parts of dmesg the parser looks at should be in a standard format anyway,
so a U+FFFD (Replacement Character) or two after the timestamp shouldn't be
too harmful.