RE: Libnet 1.1.1 RC 5

Hi guys,

I believe those warnings are the result of the use of the "bad" label prior to defining p:

    if ((payload && !payload_s) || (!payload && payload_s))     {

        sprintf(l->err_buf, "%s(): payload inconsistency\n", __FUNCTION__);
        goto bad;
    }

    ...

    p = libnet_pblock_probe(l, ptag, n,
LIBNET_PBLOCK_ICMPV4_TIMXCEED_H);
    if (p == NULL)
    {

        return (-1);
    }

Going to 'bad' at that stage, from the compilers perspective, could theoretically return 'p' uninitialized:

Do you need help?

In addition to our free technical library, Pantek provides professional IT services to companies who utilize Open Source software: Learn more about Pantek's Technical Support offerings Place an order for 24/7/365 Technical Support here Learn more about Pantek, who we are, and what we do Chat with a Live Operator Related securityfocus.com Links bugtraq certification focus-bsd focus-ids focus-ih focus-linux focus-ms focus-sun focus-unix-other focus-virus forensics incidents libnet linux-secnews ms-secnews pen-test secpapers secprog sectools secureshell security-basics securityjobs sf-news vuln-dev webappsec Request more information about Pantek

bad:

    return (ptag ? ptag : libnet_pblock_update(l, p, h,

            LIBNET_PBLOCK_ICMPV4_TIMXCEED_H)); Thanks,

Darren Bounds
Security Consultant
Information Security Services
Intrusense Inc.  

--
Intrusense - Securing Business As Usual



-----Original Message-----
From: Mike Schiffman [mailto:mike@infonexus.com] 
Sent: Thursday, June 19, 2003 3:36 AM
To: 'Frédéric Raynal'
Cc: 'Darrin Miller'; libnet@lists.securityfocus.com
Subject: RE: Libnet 1.1.1 RC 5


Thanks Fred.  WRT the ICMP warnings -- I saw these and I'm also not sure
why the compiler complains.  Anyone smart out there?

tradecraft:~/Code/Libnet-1.1.1-RC-005/src> touch libnet_build_icmp.c;
make
gcc -DHAVE_CONFIG_H -I. -I. -I../include     -g -O2 -Wall -c
libnet_build_icmp.c
libnet_build_icmp.c: In function `libnet_build_icmpv4_unreach':
libnet_build_icmp.c:268: warning: `p' might be used uninitialized in
this function
libnet_build_icmp.c: In function `libnet_build_icmpv4_timeexceed':
libnet_build_icmp.c:367: warning: `p' might be used uninitialized in
this function
libnet_build_icmp.c: In function `libnet_build_icmpv4_redirect':
libnet_build_icmp.c:464: warning: `p' might be used uninitialized in
this function

--
Mike Schiffman, CISSP 
http://www.packetfactory.net/schiffman.html 

-----Original Message-----
From: Frédéric Raynal [mailto:pappy-ml@security-labs.org] 
Sent: Thursday, June 19, 2003 12:12 AM
To: Mike Schiffman
Cc: 'Darrin Miller'; libnet@lists.securityfocus.com
Subject: Re: Libnet 1.1.1 RC 5



On Wed, Jun 18, 2003 at 08:18:10PM -0700, Mike Schiffman wrote:

> Hrm, that's probably inside libnet_raw.c.  I develop on OpenBSD


> exclusively so and I think I rm'd a line I shouldn't have.  Anyone 

> have a patch yet?  If not I'll do it later.


--- Libnet-1.1.1-RC-005.old/src/libnet_raw.c	Thu Jun 19 08:59:25 2003
+++ Libnet-1.1.1-RC-005/src/libnet_raw.c	Thu Jun 19 09:03:40 2003
@@ -112,8 +112,11 @@
 libnet_open_raw6(libnet_t *l)
 {
 #if !(__WIN32__)
+     int one = 1;
 #if (__svr4__)
      void *oneptr = &one;
+#else
+    int *oneptr = &one;
 #endif  /* __svr4__ */
 #else
     BOOL one;



There are also warnings with the 3 patched icmp functions:

libnet_build_icmp.c: In function `libnet_build_icmpv4_unreach':
Do you need more help?
In addition to our free technical library, Pantek provides professional IT services to companies who utilize Open Source software:
Learn more about Pantek's Technical Support offerings
Place an order for 24/7/365 Technical Support here
Learn more about Pantek, who we are, and what we do
Chat with a Live Operator
Related securityfocus.com Links
bugtraq
certification
focus-bsd
focus-ids
focus-ih
focus-linux
focus-ms
focus-sun
focus-unix-other
focus-virus
forensics
incidents
libnet
linux-secnews
ms-secnews
pen-test
secpapers
secprog
sectools
secureshell
security-basics
securityjobs
sf-news
vuln-dev
webappsec
Request more information about Pantek
libnet_build_icmp.c:268: warning: `p' might be used uninitialized in
this function
libnet_build_icmp.c: In function `libnet_build_icmpv4_timeexceed':
libnet_build_icmp.c:367: warning: `p' might be used uninitialized in
this function
libnet_build_icmp.c: In function `libnet_build_icmpv4_redirect':
libnet_build_icmp.c:464: warning: `p' might be used uninitialized in
this function


But I really do not understand why ... so if someone has an idea (a
solution would be to "nullify" the pointers as soon as they are
declared).


A BGP-4 builder will arrive probably today, but I'll need help for
testing as I dont have the needed infrastructure for that.

	Fred Raynal

---------------------------------------------------------------------
To unsubscribe, e-mail: libnet-unsubscribe@securityfocus.com
For additional commands, e-mail: libnet-help@securityfocus.com



---------------------------------------------------------------------
To unsubscribe, e-mail: libnet-unsubscribe@securityfocus.com
For additional commands, e-mail: libnet-help@securityfocus.com




---------------------------------------------------------------------
To unsubscribe, e-mail: libnet-unsubscribe@securityfocus.com
For additional commands, e-mail: libnet-help@securityfocus.com