freetds AT lists.ibiblio.org
Subject: FreeTDS Development Group
List archive
RE: [freetds] Crash in APACHE/PHP(compiled with sybase-ct) and Fr eeTDS 0.62.dev.20030714
- From: "Lowden, James K" <LowdenJK AT bernstein.com>
- To: 'FreeTDS Development Group' <freetds AT lists.ibiblio.org>
- Subject: RE: [freetds] Crash in APACHE/PHP(compiled with sybase-ct) and Fr eeTDS 0.62.dev.20030714
- Date: Mon, 21 Jul 2003 16:37:51 -0400
> From: Ben Vaughn [mailto:bvaughn AT BlackbirdTech.com]
> Sent: July 21, 2003 12:36 PM
>
> A new apache bug springs to life!
Looks like ours, unfortunately, but I don't see anything wrong with the
code.
> Program received signal SIGBUS, Bus error.
> 0x284cf2ad in tds_numeric_to_string (numeric=0x81b4564,
> s=0xbfbfda00 ",ê\034\b") at numeric.c:279
> 279 *--pnum = number[n - 1] * 256 + number[n];
> (gdb) bt
> #0 0x284cf2ad in tds_numeric_to_string (numeric=0x81b4564,
> s=0xbfbfda00 ",ê\034\b") at numeric.c:279
> #1 0x284ca9b5 in tds_convert_numeric (srctype=108,
What's the hardware and OS of the client, Ben?
A bus error is usually an alignment problem, but we're not doing anything
fancy on line 279. We're taking an unsigned char and implicitly promoting
it to an int (* 256), adding another unsigned char to it, and assigning it
to an unsigned in. Seems safe enough to me. Maybe it should be:
*--pnum = (unsigned int) number[n - 1] << 8 | number[n];
You could try other casts, or the attached patch, which is a little more
verbose but separates the steps and avoids the multiplication. Please let
me know if it works; I won't commit it otherwise.
--jkl
-----------------------------------------
The information contained in this transmission may contain privileged and
confidential information and is intended only for the use of the person(s)
named above. If you are not the intended recipient, or an employee or agent
responsible for delivering this message to the intended recipient, any
review, dissemination, distribution or duplication of this communication is
strictly prohibited. If you are not the intended recipient, please contact
the sender immediately by reply e-mail and destroy all copies of the original
message. Please note that we do not accept account orders and/or instructions
by e-mail, and therefore will not be responsible for carrying out such orders
and/or instructions.
Attachment:
numeric.diff
Description: Binary data
-
RE: [freetds] Crash in APACHE/PHP(compiled with sybase-ct) and Fr eeTDS 0.62.dev.20030714,
Lowden, James K, 07/21/2003
- <Possible follow-up(s)>
- RE: [freetds] Crash in APACHE/PHP(compiled with sybase-ct) and Fr eeTDS 0.62.dev.20030714, Lowden, James K, 07/22/2003
Archive powered by MHonArc 2.6.24.