D 2014-10-01T11:54:22.792 J foundin trunk J icomment If\sSQLITE_DIRECT_OVERFLOW_READ\sis\sdefined\sand\sa\slarge\stext\sor\sblob\sfield\sthat\sis\saligned\swith\sthe\sstart\sof\san\soverflow\spage\sis\sread,\sSQLite\smay\stemporarily\smodify\s(and\sthen\srestore)\sthe\scontents\sof\sup\sto\s4\sbytes\sof\sspace\simmediately\sbefore\sa\sbuffer\sobtained\sfrom\smalloc().\sHere:\s\r\n\r\n\s\s[http://www.sqlite.org/src/artifact/ede8348a7d62?ln=4166]\r\n\r\nNormally\sthis\sis\snot\sa\sproblem,\sas\sthe\sdefault\smalloc\simplementation\sused\sby\sSQLite\salways\sallocates\sat\sleast\s4\sbytes\sof\sspace\sfor\sbookkeeping\spurposes\sbefore\seach\sbuffer\sreturned\sto\sSQLite.\sHowever,\ssome\scustom\smalloc\simplemenations,\sor\soccasionally\sthe\sbuilt-in\smemsys3\sor\smemsys5\simplemenations,\smay\snot\sdo\sthis.\sIn\sthose\scases\sthe\sresults\sare\sundefined.\r\n\r\nProblem\shas\sexisted\sfor\sas\slong\sas\sSQLITE_DIRECT_OVERFLOW_READ\shas.\sIntroduced\sby\s[2ab14a8467].\sFirst\spublished\sin\sversion\s3.7.9. J login dan J mimetype text/x-fossil-plain J severity Important J status Open J title out-of-bounds\swrite\swhen\susing\snon-default\smalloc\simplementation\sand\sSQLITE_DIRECT_OVERFLOW_READ J type Code_Defect K e3a290961a63239fc1fb3d187e5c8d737dd7e6d2 U dan Z 12aa632ba9bfb02374ebca402b402518