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parser json BUGFIX use-after-free of escaped member names - #2593
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A member name containing escape sequences is decoded into a buffer owned by the JSON context, which is freed by the next lyjson_ctx_next(). lydjson_meta_attr_instance() and lydjson_envelope() kept using the name/prefix pointing into it after that call, so take ownership of the buffer the same way lydjson_subtree_r() does.
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Um, yes, thanks, I will also fix the tests. But I have changed the base branch to |
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Repro: parse
{"a:foo":"xxx","@a:foo":{"a:hin\u0074":1}}with an ASan build, or runregress_fuzz_lyd_parse_mem_jsonon the existingpull1626corpus file; both report a heap-use-after-free (inly_strncmpfromlyd_get_meta_annotation, and indict_insertfromlyd_create_attr). A RESTCONF notification starting with{"ietf-restconf:notificatio\u006e":...}hits the same thing inlyd_create_opaqvialydjson_envelope().Cause: a member name with escapes is decoded into a buffer owned by the JSON context, and
lydjson_meta_attr_instance()/lydjson_envelope()keepname/prefixpointing into it across thelyjson_ctx_next()that frees it.Fix: take ownership with
lyjson_ctx_give_dynamic_value(), same aslydjson_subtree_r()already does for node names. Both cases are covered intest_parser_json.c; they abort under ASan without the fix, and the full ctest run (including the fuzz regression) passes with it.