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Fix GH-16234 jewishtojd overflow on year argument. #16243

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Fix GH-16234 jewishtojd overflow on year argument. #16243

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Fix GH-16234 jewishtojd overflow on year argument.
devnexen Oct 5, 2024
7861be9
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devnexen Oct 6, 2024
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19 changes: 17 additions & 2 deletions ext/calendar/jewish.c
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Original file line number Diff line number Diff line change
Expand Up @@ -433,16 +433,31 @@ static void MoladOfMetonicCycle(
zend_long *pMoladHalakim)
{
register zend_ulong r1, r2, d1, d2;
zend_long chk;

/* Start with the time of the first molad after creation. */
r1 = NEW_MOON_OF_CREATION;
chk = (zend_long)metonicCycle;
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Note that if zend_long is 32-bit longs, you still have an issue.
Furthermore, I think the failure should be propagated instead of silently set to 0.

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Furthermore, I think the failure should be propagated instead of silently set to 0.

That sounds more a change for master ?


if (chk > (ZEND_LONG_MAX - NEW_MOON_OF_CREATION) / (HALAKIM_PER_METONIC_CYCLE & 0xFFFF)) {
*pMoladDay = 0;
*pMoladHalakim = 0;
return;
}

/* Calculate metonicCycle * HALAKIM_PER_METONIC_CYCLE. The upper 32
* bits of the result will be in r2 and the lower 16 bits will be
* in r1. */
r1 += metonicCycle * (HALAKIM_PER_METONIC_CYCLE & 0xFFFF);
r1 += chk * (HALAKIM_PER_METONIC_CYCLE & 0xFFFF);
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This can still overflow, because r1 starts with NEW_MOON_OF_CREATION.
Analogous for r2.


if (chk > (ZEND_LONG_MAX - (r1 >> 16)) / ((HALAKIM_PER_METONIC_CYCLE >> 16) & 0xFFFF)) {
*pMoladDay = 0;
*pMoladHalakim = 0;
return;
}

r2 = r1 >> 16;
r2 += metonicCycle * ((HALAKIM_PER_METONIC_CYCLE >> 16) & 0xFFFF);
r2 += chk * ((HALAKIM_PER_METONIC_CYCLE >> 16) & 0xFFFF);

/* Calculate r2r1 / HALAKIM_PER_DAY. The remainder will be in r1, the
* upper 16 bits of the quotient will be in d2 and the lower 16 bits
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11 changes: 11 additions & 0 deletions ext/calendar/tests/gh16234.phpt
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Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
--TEST--
GH-16234 jewishtojd overflow on year argument
--EXTENSIONS--
calendar
--FILE--
<?php
jewishtojd(1218182888, 1, 1218182888);
echo "DONE";
?>
--EXPECT--
DONE
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