segmentation error while using mpz_powm in a loop

David Crow

My, point, although subtle, was to ensure that the values you are passing to that function are valid. Some functions/libraries place the onus of validation solely on the caller (rather than handle the bad input and fail gracefully)

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shrims4u

yah the values that are passed are proper... The gdb output is as follows.... [New Thread -1208882288 (LWP 9012)] [New Thread -1208879424 (LWP 9009)] [New Thread -1219372144 (LWP 9017)] GNU MP: Cannot allocate memory (size=3368600780) Program received signal SIGABRT, Aborted. [Switching to Thread -1219372144 (LWP 9017)] 0x00110402 in __kernel_vsyscall ()

shrims4u

Also i get this message from gdb..... Program received signal SIGSEGV, Segmentation fault. [Switching to Thread -1218634864 (LWP 9064)] 0x06d0199c in __gmpz_powm () from /usr/lib/sse2/libgmp.so.3

jeron1

You certainly did not deserve to be down voted for that response.

molesworth

shrims4u wrote:

GNU MP: Cannot allocate memory (size=3368600780)

I would guess that this is related to the problem. It's tried to allocate 3 Gb of memory, and failed... As to why it's trying to allocate such a big chunk of memory, I couldn't say, but maybe stepping through until you get that error might help pin it down.

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shrims4u

i dint understand??? wat is down voting???

shrims4u

ill mail the whole program to uall Actually it is a milter which decrypts the incoming mail messages... /* sample_milter - example mail filter module ** ** Copyright © 2004 by Jef Poskanzer . ** All rights reserved. ** ** Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions ** are met: ** 1. Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** 2. Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in the ** documentation and/or other materials provided with the distribution. ** ** THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ** ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS ** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) ** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF ** SUCH DAMAGE. ** ** For commentary on this license please see http://www.acme.com/license.html */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "libmilter/mfapi.h" ////////////////////////////////////////////////////////////// #include "gmp.h" /* Forwards. */ static void usage( void ); static sfsistat sample_connect( SMFICTX* ctx, char* connhost, _SOCK_ADDR* connaddr ); static sfsistat sample_helo( SMFICTX* ctx, char* helohost ); static sfsistat sample_envfrom( SMFICTX* ctx, char** fromargs ); static sfsistat sample_envrcpt( SMFICTX* ctx, char** rcptargs ); static sfsistat sample_header( SMFICTX* ctx, char* name, char* value ); static sfsistat sample_eoh( SMFICTX* ctx ); static sfsistat sample_body( SMFICT

jeron1

When a response receives a 1 vote (located at the bottom right of the response).

shrims4u

will you please help me??? you understood my problem?

shrims4u

I dint understand what you want me to do...

molesworth

Somewhere the program is trying to allocate a very large amount of memory. This is, I think, the cause of your problem. I haven't used this library/package, but I'm basing my conclusion on the error mesage you posted (see my last reply). What I suggest is that you use a debugging tool to step through the program until it generates that error, and take a close look at exactly what is happening at that point. Or post here exactly which line is causing the problem.

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