Hi,
2011-11-17 14:53 keltezéssel, Michael Meskes írta:
> On Mon, Nov 14, 2011 at 09:06:30AM +0100, Boszormenyi Zoltan wrote:
>> Yes, you are right. For timestamp and interval, the safe alignment is int64.
>> Patch is attached.
> Applied, thanks.
>
> Michael
thanks.
Hopefully last turn in this topic. For NUMERIC types, the safe minimum
alignment is a pointer because there are 5 int members followed by
two pointer members in this struct. I got a crash from this with a lucky
query and dataset. The DECIMAL struct is safe because the digits[] array
is embedded there.
After fixing this, I got another one at an innocent looking memcpy():
memcpy((char *) sqlda + offset, num->buf, num->ndigits + 1);
It turned out that when the server sends "0.00", PGTYPESnumeric_from_asc()
constructs a numeric structure with:
ndigits == 0
buf == NULL
digits == NULL.
This makes memcpy() crash and burn. Let's also fix this case.
Best regards,
Zoltán Böszörményi
--
----------------------------------
Zoltán Böszörményi
Cybertec Schönig & Schönig GmbH
Gröhrmühlgasse 26
A-2700 Wiener Neustadt, Austria
Web: http://www.postgresql-support.de
http://www.postgresql.at/
--- postgresql-9.1.1/src/interfaces/ecpg/ecpglib/sqlda.c.orig 2011-11-19
21:13:25.699169076 +0100
+++ postgresql-9.1.1/src/interfaces/ecpg/ecpglib/sqlda.c 2011-11-19
22:50:13.895653223 +0100
@@ -110,7 +110,7 @@
* int Unfortunately we need to do double work
here to compute
* the size of the space needed for the numeric
structure.
*/
- ecpg_sqlda_align_add_size(offset, sizeof(int),
sizeof(numeric), &offset, &next_offset);
+ ecpg_sqlda_align_add_size(offset,
sizeof(NumericDigit *), sizeof(numeric), &offset, &next_offset);
if (!PQgetisnull(res, row, i))
{
char *val = PQgetvalue(res, row,
i);
@@ -119,7 +119,8 @@
num = PGTYPESnumeric_from_asc(val,
NULL);
if (!num)
break;
- ecpg_sqlda_align_add_size(next_offset,
sizeof(int), num->ndigits + 1, &offset, &next_offset);
+ if (num->ndigits)
+
ecpg_sqlda_align_add_size(next_offset, sizeof(int), num->ndigits + 1, &offset,
&next_offset);
PGTYPESnumeric_free(num);
}
break;
@@ -323,7 +324,7 @@
set_data = false;
- ecpg_sqlda_align_add_size(offset,
sizeof(int), sizeof(numeric), &offset, &next_offset);
+ ecpg_sqlda_align_add_size(offset,
sizeof(NumericDigit *), sizeof(numeric), &offset, &next_offset);
sqlda->sqlvar[i].sqldata = (char *)
sqlda + offset;
sqlda->sqlvar[i].sqllen =
sizeof(numeric);
@@ -343,11 +344,14 @@
memcpy(sqlda->sqlvar[i].sqldata, num,
sizeof(numeric));
- ecpg_sqlda_align_add_size(next_offset,
sizeof(int), num->ndigits + 1, &offset, &next_offset);
- memcpy((char *) sqlda + offset,
num->buf, num->ndigits + 1);
+ if (num->ndigits)
+ {
+
ecpg_sqlda_align_add_size(next_offset, sizeof(int), num->ndigits + 1, &offset,
&next_offset);
+ memcpy((char *) sqlda + offset,
num->buf, num->ndigits + 1);
- ((numeric *)
sqlda->sqlvar[i].sqldata)->buf = (NumericDigit *) sqlda + offset;
- ((numeric *)
sqlda->sqlvar[i].sqldata)->digits = (NumericDigit *) sqlda + offset +
(num->digits - num->buf);
+ ((numeric *)
sqlda->sqlvar[i].sqldata)->buf = (NumericDigit *) sqlda + offset;
+ ((numeric *)
sqlda->sqlvar[i].sqldata)->digits = (NumericDigit *) sqlda + offset +
(num->digits - num->buf);
+ }
PGTYPESnumeric_free(num);
@@ -509,7 +513,7 @@
set_data = false;
- ecpg_sqlda_align_add_size(offset,
sizeof(int), sizeof(numeric), &offset, &next_offset);
+ ecpg_sqlda_align_add_size(offset,
sizeof(NumericDigit *), sizeof(numeric), &offset, &next_offset);
sqlda->sqlvar[i].sqldata = (char *)
sqlda + offset;
sqlda->sqlvar[i].sqllen =
sizeof(numeric);
@@ -529,11 +533,14 @@
memcpy(sqlda->sqlvar[i].sqldata, num,
sizeof(numeric));
- ecpg_sqlda_align_add_size(next_offset,
sizeof(int), num->ndigits + 1, &offset, &next_offset);
- memcpy((char *) sqlda + offset,
num->buf, num->ndigits + 1);
+ if (num->ndigits)
+ {
+
ecpg_sqlda_align_add_size(next_offset, sizeof(int), num->ndigits + 1, &offset,
&next_offset);
+ memcpy((char *) sqlda + offset,
num->buf, num->ndigits + 1);
- ((numeric *)
sqlda->sqlvar[i].sqldata)->buf = (NumericDigit *) sqlda + offset;
- ((numeric *)
sqlda->sqlvar[i].sqldata)->digits = (NumericDigit *) sqlda + offset +
(num->digits - num->buf);
+ ((numeric *)
sqlda->sqlvar[i].sqldata)->buf = (NumericDigit *) sqlda + offset;
+ ((numeric *)
sqlda->sqlvar[i].sqldata)->digits = (NumericDigit *) sqlda + offset +
(num->digits - num->buf);
+ }
PGTYPESnumeric_free(num);
--
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