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sr #110745: Unexpected space in conditional taints subsequent conditional

Submitter:  None
Submitted:  Wed 19 Oct 2022 07:54:28 PM UTC
Category:  None Priority:  5 - Normal
Severity:  3 - Normal Status:  Done
Privacy:  Public Assigned to:  None
Originator Email:  -email is unavailable- Open/Closed:  Open
Operating System:  GNU/Linux
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Thu 20 Oct 2022 05:02:51 PM UTC, comment #1: 

Thanks for the report. It's not the space, but the syntax error
(`b' is not a valid binary operator). The parser error recovery
token doesn't result in the parser state being reset correctly.

It's an interactive-only issue. It will be fixed in the next  devel branch push.


Chet Ramey <chet>
Group administrator
Wed 19 Oct 2022 07:54:28 PM UTC, original submission:  

Bash Version: 5.2
Patch Level: 2
Release Status: release

Including an erroneous space in a double-bracket conditional results in an error, as it should, but it also taints the next conditional that gets interpreted, forcing an an exit status of 2 regardless of syntax. This taint persists through non-conditional commands.

Here's an example of the issue. Note that the first echo (in the third command) does not execute -- the entire line seems to be eaten.

$ [[ a b ]]
bash: conditional binary operator expected
$ date
Tue Oct 18 09:17:20 PM PDT 2022
$ [[ a ]]; echo $?
bash: syntax error near unexpected token `a'
$ echo $?
$ [[ a ]]; echo $?

This also happens with other types of conditional expressions. Note that the initial error is different in this example, but the taint still occurs.

$ [[ "a b" =~ a b ]] && echo "match"
bash: syntax error in conditional expression
$ [[ $((1+1)) == 2 ]] && echo "Yay, MATH"
bash: syntax error near unexpected token `$((1+1))'
$ [[ $((1+1)) == 2 ]] && echo "Yay, MATH"

This does not happen in bash 3.2.57 or zsh 5.8.

Best regards,



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    Date Changed by Updated Field Previous Value => Replaced by
    2022-10-20 chet StatusNone Done

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