Fix GH-17399: iconv memory leak with large line-length#12
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Fix GH-17399: iconv memory leak with large line-length#12
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Move the buf allocation in _php_iconv_mime_encode() before the iconv_open() calls. When max_line_len is excessively large (e.g. PHP_INT_MAX), safe_emalloc triggers an OOM bailout that skips cleanup, leaking the iconv handles allocated via system malloc. By allocating buf first, a bailout happens before any iconv handles exist. Closes phpGH-17399
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Submitted upstream as php#21541 |
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Summary
_php_iconv_mime_encode()opens twoiconv_thandles via systemmalloc, then callssafe_emalloc(1, max_line_len, 5). Whenmax_line_lenisPHP_INT_MAX, the allocation triggers an OOM bailout that skipsiconv_close()cleanup, leaking both handles.Fix: move
safe_emallocbefore bothiconv_open()calls. If it bails out, no handles exist to leak.@cmb69 suggested this approach in the issue thread.
Test plan
ext/iconv/tests/gh17399.phpttriggers the OOM pathext/iconv/tests/suite passes with zero regressions