[SOLVED] +++ Segmentation fault !

hooxs · 09-28-2012, 01:03 PM

!!!!!!!!!!!!

dwhitney67 · 09-28-2012, 01:52 PM

Debug your application!

Compile it like this:

Code:

gcc -g juno.c -o juno

Then put it in the debugger:

Code:

gdb ./juno

Once you see the gdb prompt, enter "run".

Code:

(gdb) run

When it crashes with the segfault, perform a back-trace:

Code:

(gdb) backtrace

Let us know what you find.

JohnGraham · 09-28-2012, 01:57 PM

When compiling, I get one warning that may cause a segfault. With -Wall I get other warnings. Fix them before doing anything else, or you're just wasting your time.

hooxs · 09-28-2012, 02:14 PM

!!!!!!!!!!!!

dwhitney67 · 09-28-2012, 02:18 PM

Quote:

Originally Posted by hooxs

Syntax: /root/juno <target ip> <target port>

Program exited with code 01.

That warning is coming from this bit of code:

Code:

   if(argc<TARGET_IP_INDEX+2) {
  fprintf(stderr,"Syntax: %s ",argv[0]);
#ifndef RANDOMIZE_SOURCE_IP
  fprintf(stderr,"<source ip> ");
#endif
#ifndef RANDOMIZE_SOURCE_PORT
  fprintf(stderr,"<source port> ");
#endif
  fprintf(stderr,"<target ip> <target port>\n");
  exit(1);
   }

You will need to supply gdb with the run-time arguments. For example:

Code:

(gdb) run 192.168.1.10 8000

In other words, supply an IP address and a Port Number.

hooxs · 09-28-2012, 02:22 PM

!!!!!!!!!!!!

hooxs · 09-28-2012, 03:34 PM

!!!!!!!!!!!!

hooxs · 09-28-2012, 04:18 PM

!!!!!!!!!!!!

johnsfine · 09-28-2012, 05:00 PM

I assume you didn't write this program, someone else did.

I assume whoever that was, only tested the program on a 32 bit OS.

I see you are compiling it on a 64 bit OS. Fixing the bugs that cause it to fail when compiled for 64 bits would be appropriate if it were you own program. But that might not be the best approach for your current needs.

If decent 32 bit support is installed in your 64 bit Linux system, I think you can get the program to work by compiling it as a 32 bit program, which may be as simple as using

Code:

gcc -m32 -O2 juno.c -o juno

instead of

Code:

gcc -O2 juno.c -o juno

I'm pretty sure the bug symptoms are only driven the architecture of the program itself, not by the architecture of the OS. So as a 32 bit program on a 64 bit OS, I think the program is likely to work.

Even if the program runs apparently correctly (free of seg faults or other of what I am calling bug symptoms) when compiled for 32 bit, that does not mean the program is free of actual bugs under those conditions. This program has enough bugs it is hard to even judge the intent well enough to fix the bugs. But the bugs might be symptom free in a 32 bit build. I wouldn't know without trying and I don't know whether you posted enough for me to try nor whether trying would be wise if I could.

hooxs · 09-28-2012, 05:17 PM

!!!!!!!!!!!!

johnsfine · 09-28-2012, 05:27 PM

Quote:

Originally Posted by johnsfine

If decent 32 bit support is installed in your 64 bit Linux system

Quote:

Originally Posted by hooxs

Code:

[root@vps ~]# gcc -m32 -O2 juno.c -o juno
In file included from /usr/include/features.h:352,
                 from /usr/include/string.h:26,
                 from juno.c:15:
/usr/include/gnu/stubs.h:7:27: error: gnu/stubs-32.h: No such file or directory

!!!

OK, you have dis-proven my guess that decent 32 bit support is installed on your Linux system.

I previously read a lot of facts you didn't state into some of the obscure details you did post.

But suddenly I'm failing to notice the hooks from which to deduce other such facts. So maybe you can give us some background such as what distribution you are using, what package manager you use (and whether you actually know how to use it etc.) that might be relevant to the question of whether installing some 32 bit support is worth your trouble.

I still think a 32 bit build of your program is likely to work. But I can't promise that. I don't know how hard it would be for you to install 32 bit support or your system in order to find out.

hooxs · 09-28-2012, 05:33 PM

!!!!!!!!!!!!

johnsfine · 09-28-2012, 05:47 PM

For example, if your distribution is Ubuntu, there is a web site (which I just checked) for finding the package for any missing file. For the first file whose absence caused -m32 to fail for you, I found:

http://packages.ubuntu.com/search?se...ecise&arch=any

That says you need the package libc6-dev-i386

I think there is some meta package of 32 bit support that includes that package plus several related ones you might also need. But I never remember the name of that meta package nor how to look it up. If any Debian or Ubuntu experts are reading this, I expect one of them will remember what I mean.

hooxs · 09-28-2012, 05:49 PM

!!!!!!!!!!!!

johnsfine · 09-28-2012, 05:54 PM

Quote:

Originally Posted by hooxs

Sir I'm Using Centos - 5.5 - x86_64

!

I don't have admin control of my Centos systems, so I can't check this. But I think the command to install what you need is:

Code:

yum install glibc.i386 glibc-devel.i386

If any Centos or RHEL experts are reading this, they might comment on that.