Description:
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In incorrect data passed to session_decode function PHP engine may crash.

Reproduce code:
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Made session dump with:
 $f=fopen("$name.profile","w");
 fwrite($f,session_encode());
 fclose($f);

and then if partial read was made before decoding session:
 $t=fread($f,65000); instead of $t=fread($f,filesize("$name.profile"));
so, now in $t there is unclosed strings, brackets..
Now try to make session_decode($t) and php probably crash.


Expected result:
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WinXP shows exeption for apache process