ID: 39460
User updated by: ben at thelemite dot freeserve dot co dot uk
Reported By: ben at thelemite dot freeserve dot co dot uk
Status: Open
Bug Type: MSSQL related
Operating System: Solaris 10
PHP Version: 5.2.0
New Comment:
Just to clarify; it segfaults both in apache mod and cli. SQL Server
2003 is being used. built using gcc 3.4.6, and mssql is built-in (not
DSO loaded)
Previous Comments:
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[2006-11-10 12:44:31] ben at thelemite dot freeserve dot co dot uk
Description:
------------
Executing SELECT * queries on tables that contain 64-bit values (such
as bigints) cause a seg fault. Segfault occurs in
php_mssql_get_column_content_with_type within php_mssql.c
It's probably system dependent but has been verified on a separate
Solaris 10 setup.
Note the following things though:
1) Running queries containing 64-bit fields that do not contain the
primary key do not seem to cause the crash, e.g: "SELECT value from
TestTable", but individually selecting fields does, e.g: "SELECT
id,value". Bizzarely "SELECT value,id" doesn't cause a crash.
2) There seems to be some weird allocation issues going on that I have
not been able to get to the bottom of. In
php_mssql_get_column_content_with_type there is:
case SQLFLT8:
ZVAL_DOUBLE(result, (double) floatcol8(offset));
break;
If I change it to:
case SQLFLT8:
{
DBFLT8 res_buf;
memcpy(&res_buf, &floatcol8(offset), 8);
ZVAL_DOUBLE(result, res_buf);
}
break;
It cures the problem! But (very bizzarely), the following code still
crashes:
res_buf = *(DBFLT8 *)dbdata(mssql_ptr->link,offset);
ZVAL_DOUBLE(result, res_buf);
BUT... It does not crash at the point of reading the data into res_buf.
It's crashes when something is done with the value! (Possibly FreeTDS
is corrupting the stack?).
Help!
SunOS 5.10 Generic_118833-17 sun4u sparc SUNW,Ultra-60
PHP 5.1.6 (cli) (built: Oct 26 2006 15:30:54) [same on 5.2.0 as well
though]
FreeTDS 0.63
Reproduce code:
---------------
Table I have been using for experimenting:-
TestTable {
id, int
value, bigint
}
PHP code to generate crash:-
$link = mssql_connect("MyServer","MyUser","MyPassword");
$q = mssql_query("SELECT * from TestTable");
echo $q;
Expected result:
----------------
Resource id #X
Actual result:
--------------
nothing (segfaults when run from CLI)
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Edit this bug report at http://bugs.php.net/?id=39460&edit=1
