Re^2: Bug in perl command line processing?

[demerphq]

in reply to Re: Bug in perl command line processing?
in thread Bug in perl command line processing?

The -e1 is unnecessary.

$ perl -MO=Deparse -i'foo e eval "warn q[bar]";'
BEGIN { $^I = "foo"; }
eval 'warn q[bar]';
-e syntax OK

I vote bug.

[davido]

The -e1 is unnecessary.

That seems to be because perl sees the 'e' in 'foo e eval...' as an -e command line switch. Change it to something else besides 'e' and the behavior changes.

It sort of feels like the same sort of exploit one should worry about when using the two-arg open unsafely, passing user data to a database without placeholders, or instantiating user data as variable names.

[demerphq]

Yes, but to me that is THE bug.

[davido]

Absolutely.

BTW: It doesn't seem to propagate into full-fledged scripts like this:

#!/usr/bin/perl -i'foo e eval "warn q[bar]" '
1;

From what I can tell, -i has to actually appear on the command-line, which hopefully self-limits its significance as a tool for exploit.

[sauoq]

The -e1 is unnecessary.

Yes, sorry. I should have explained my intent... I was showing that by adding the ';' to the OP's you could include -e1 without an error.