fix: avoid NULL deref in cjson.encode_indent() with no args / nil#124
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perfgao wants to merge 1 commit into
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fix: avoid NULL deref in cjson.encode_indent() with no args / nil#124perfgao wants to merge 1 commit into
perfgao wants to merge 1 commit into
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…gs / nil DEFAULT_ENCODE_INDENT is NULL and json_string_option skips assignment when the argument is nil, so cfg->encode_indent[0] dereferenced NULL and crashed. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
Calling
cjson.encode_indent()orcjson.encode_indent(nil)crashes with SIGSEGV.Root cause:
DEFAULT_ENCODE_INDENTisNULL(lua_cjson.c:95).json_string_optionskips assignment when the argument is nil, socfg->encode_indentstays NULL, and the subsequentcfg->encode_indent[0] == '\0'check at line 436 dereferences NULL.Fix: NULL-check before reading the first byte.
Repro
Test plan
cjson.encode_indent()no longer crashes; returns current indent setting.cjson.encode_indent(nil)same as above.cjson.encode_indent(" ")still works.