)]}'
{
  "commit": "f3c6b3ab929fad6c653af8b70880c92492c8e681",
  "tree": "ea354c6ba68ff23d0b599b6279623c8b9e039920",
  "parents": [
    "fd0360d985b43599c691d7f18cb954b9b715286f"
  ],
  "author": {
    "name": "Behdad Esfahbod",
    "email": "behdad@behdad.org",
    "time": "Mon May 18 15:11:34 2026 -0600"
  },
  "committer": {
    "name": "GitHub",
    "email": "noreply@github.com",
    "time": "Mon May 18 15:11:34 2026 -0600"
  },
  "message": "[algs] Saturating arithmetic for get_size() on 32-bit (#5988)\n\nOn 32-bit platforms size_t is unsigned int, so the typical\nget_size() computation `min_size + count * static_size`\nsilently wraps when the product exceeds UINT_MAX.  The\ntruncated value then flows into sanitize / serialize as a\nsmall but plausible size, defeating bounds checks.\n\nAdd three helpers in hb-algs.hh:\n\n  hb_unsigned_mul_saturate (a, b, ...)\n  hb_unsigned_add_saturate (a, b, ...)\n  hb_unsigned_mul_add_saturate (a, b, c)   /* a*b + c */\n\nThey saturate to SIZE_MAX on overflow.  Variadic overloads\nleft-fold so 3+ arguments work.  On 64-bit (size_t wider than\nunsigned int), all three reduce to plain a*b / a+b — the\ninputs to size computations are at most unsigned int so the\nresult fits in size_t without overflow.\n\nConvert every get_size() that does arithmetic over variable\ninputs:\n\n  hb-open-type.hh        UnsizedArrayOf, ArrayOf,\n                         HeadlessArrayOf, ArrayOfM1,\n                         sorted-array-with-header, CFFIndex\n  hb-ot-layout-common.hh CmapSubtableFormat-style,\n                         VarRegionList, VarData, MultiVarData,\n                         DeltaSetIndexMapFormat01\n  hb-ot-hdmx-table.hh    DeviceRecord, hdmx\n  hb-ot-cff-common.hh    Charset0, Charset wrapper\n  hb-ot-cff1-table.hh    Encoding, Charset wrapper\n                         (also widened unsigned accumulator\n                         to size_t)\n  hb-ot-os2-table.hh     OS/2 (widened accumulator to size_t)\n  hb-ot-var-common.hh    TupleVariationHeader,\n                         TupleVariationData accumulator\n  hb-ot-var-hvar-table.hh DeltaSetIndexMap\n  hb-vector.hh           hb_vector_t::get_size\n\nWhen saturation kicks in, check_range() and extend_size()\nnaturally reject the resulting value (SIZE_MAX truncated to\nunsigned is UINT_MAX, far past any real blob; extend_size\nalready rejects sizes \u003e\u003d INT_MAX).\n\nAssisted-by: Claude \u003cnoreply@anthropic.com\u003e",
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