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ly common BUGFIX reject overlong 4-byte UTF-8 sequences - #2618
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ly_getutf8() accepted 4-byte sequences decoding to 0x1000 - 0xFFFF, which are overlong forms of 3-byte characters, including the UTF-16 surrogates rejected by the 3-byte branch. The XML and JSON parsers use it to check values that are then stored with is_utf8 set, so these sequences were accepted and printed back verbatim, while ly_checkutf8() used for the other inputs rejects them.
michalvasko
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Nov 3, 2026
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Thanks, looks fine, but change the base branch to devel again.
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ly_getutf8()used0x1000as the lower bound for 4-byte sequences instead of0x10000, so the XML and JSON parsers accepted overlong forms such asF0 81 80 80(U+1000) orF0 8D A0 80(a surrogate the 3-byte branch rejects), and since those values are stored withis_utf8set they skiply_checkutf8()and get printed back as invalid UTF-8 thatlyd_new_term()would have refused and strict parsers like expat choke on; the new cases intypes/string.cfail without the fix.