From mboxrd@z Thu Jan 1 00:00:00 1970 From: Holger Kiehl Subject: Re: Question about core files Date: Fri, 9 Oct 2009 12:09:03 +0000 (GMT) Message-ID: References: Mime-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="646810922-1074793909-1255090143=:12677" Return-path: In-Reply-To: Sender: linux-c-programming-owner@vger.kernel.org List-ID: To: Manish Katiyar Cc: linux-c-programming@vger.kernel.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --646810922-1074793909-1255090143=:12677 Content-Type: TEXT/PLAIN; charset="iso-8859-1"; format="flowed" Content-Transfer-Encoding: quoted-printable Hello Manish First, sorry for the late responce! On Wed, 7 Oct 2009, Manish Katiyar wrote: > On Wed, Oct 7, 2009 at 7:51 PM, Holger Kiehl wrote: >> Hello Manish >> >> On Wed, 7 Oct 2009, Manish Katiyar wrote: >> >>> Hi Holger, >>> >>> I don't have the source code, so a bit hard to guess. But you can try >>> to find out which member of your fsa structure is at offset 236 (0xec) >>> and look around those lines in the function where you are accessing >>> that member. >>> >>> I am trying to download the AFD source code, which looks like it will >>> take ages on my slow broadband. Hopefully I can help after that. >>> >> If you download, please take afd-1.4.0-0.20.beta.tar.bz2 because that >> is the one that caused the error. You can get it from: >> >> =A0 ftp://ftp.dwd.de/pub/afd/development/afd-1.4.0-0.20.beta.tar.bz2 >> >> You will find the relevant code in src/fd.c. > > Hi Holger, > > (gdb) set $offset =3D (int)(&((struct filetransfer_status *)0)->host_stat= us) > (gdb) p $offset > $5 =3D 236 > (gdb) p/x 236 > $6 =3D 0xec > > host_status is at offset 236. In the function start_process I can see > that this is used at places by dereferencing below > "fsa[fsa_pos].host_status ". > > At this point my guess would be that you are getting fsa_pos as > something illegal ie.. probably you are trying to access beyond the > array. Since this is an input to the function, you can just check its > value at the start and assert if that is ok and within reasonable > range. > > HTH > Many thanks for finding this out! I think I now, with your help, have a clue where the error could be. Is there a way to find out what value fsa_pos had at that time? If it was -1 then it is definitely the error I am thinking of, but if it is something else then I don't know. Again many thanks for the valuable help! Regards, Holger --646810922-1074793909-1255090143=:12677--