Error-checking for all utf8proc_iterate calls where invalid UTF-8 (or injection of same via HTML entities) may cause loops not to terminate #703
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…lled and may return an error which can cause the iteration not to make forward progress. This includes fixing a bug where injecting invalid UTF-8 through a series of HTML-encoded codepoints can cause the C library to hang. Note: we're not fixing all the garbage encoding in the world, so if encoding is bad the output of expand_address may not be useful but it won't hang. Fixes #448
Kontinuation
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Jul 2, 2025
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737
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+738
| log_warn("transliterator \"%s\" does not exist in trie\n", trans_name); | ||
| if (allocated_trans_name) free(trans_name); |
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Is it a double-free here? trans_name has already been freed on line 718.
The usage of trans_name in log_warn may also be a use-after-free if it is strdup-ed and then freed.
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ah, good catch, hotfixing that by just removing 718 so it's effectively moved to the end of the function. The purpose of adding it in all the other places was to avoid a segfault in the log_warn line.
This was referenced Jul 2, 2025
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Reviewed and fixed all points where utf8proc_iterate is called and may return an error which can cause the iteration not to make forward progress. This includes fixing a bug where injecting invalid UTF-8 through a series of HTML-encoded codepoints can cause the C library to hang. Note: we're not fixing all the garbage encoding in the world, so if encoding is bad the output of expand_address may not be useful but it won't hang. Fixes #448