Do not escape malformed URI twice when sending ICP errors #2374
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Authored-by: Joshua Rogers <megamansec@gmail.com> In this context, escaping escaped URI always produces incorrect URI because `%` character in the escaped URI gets escaped again. Feeding the result of the first rfc1738_escape() call to the second call is also dangerously wrong because the result of the first call gets invalidated during the second call. No other cases of such "chained" rfc1738_escape() calls were found. Broken since 2002 commit e6ccf24.
rousskov
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I developed this fix independently, but I am attributing it to @MegaManSec because Joshua made the same code change in #2220. That PR description does not discuss that change. Since addressing other problems in that PR requires a lot more efforts and may take some time, I decided to post this small fix as a separate PR.
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This reverts commit 9af3d82. That change is correct, but it addresses a rather different bug, and it may be best to merge it separately (via squid-cache#2374).
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In this context, escaping escaped URI always produces incorrect URI because `%` character in the escaped URI gets escaped again. Feeding the result of the first rfc1738_escape() call to the second call is also dangerously wrong because the result of the first call gets invalidated during the second call. No other cases of such "chained" rfc1738_escape() calls were found. Broken since 2002 commit e6ccf24.
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Authored-by: Joshua Rogers megamansec@gmail.com
In this context, escaping escaped URI always produces incorrect URI
because
%character in the escaped URI gets escaped again. Feeding theresult of the first rfc1738_escape() call to the second call is also
dangerously wrong because the result of the first call gets invalidated
during the second call.
No other cases of such "chained" rfc1738_escape() calls were found.
Broken since 2002 commit e6ccf24.