Bugtraq mailing list archives
Urgent !! Serious Linux Security Bug....
From: usa () win95 com (Jake the Prince)
Date: Sat, 19 Oct 1996 18:43:39 +0200
This is a multi-part message in MIME format. --------------BFF22A370E3 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Hi, Today we saw an email from Linus Torvalds advising of a problem with Linux and ping. Basically you can reboot a linux box remotely if some scenario's are right. From what we can tell and this has all been verified is: If anyone in the world with a Windows 95 machine can ping your Linux box they can potentially reboot that machine.. Hence a serious denial of service OR loss of data. Scenario: Win95 user types 'ping -l 65510 host.running.linux'. Result: That machine reboots OR freezes. On the Linux machine, you need to be running kernel version 2.0.7(It's the lowest we run) up to version 2.0.20(The highest we're running). With ping you can use value 65508-65527. We have extensively tested both of these. I'm sure there are thousands of Linux systems that could be affected. There IS a BETA patch out and it DOES work.. If you don't have that patch code as of yet, it's attached. Cyaz Jake The Prince PS..... Thanks to whoever found this serious bug... - /-----------------------------------------------------------\ | I have just one \|/ ____ \|/ | | thing to say... ~@-/ oO \-@~ Neener, neener, neener. | | /_( \__/ )_\ | | \__U_/ | | | | -*- Opp -*- (usa () win95 com) -*- USA_Direkt -*- | \-----------------------------------------------------------/ --------------BFF22A370E3 Content-Type: text/plain; charset=us-ascii; name="ping.bug" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="ping.bug" --- ip_fragment.c.old Mon Sep 16 22:14:52 1996 +++ ip_fragment.c Sat Oct 19 01:04:47 1996 @@ -366,7 +366,7 @@ { NETDEBUG(printk("Invalid fragment list: Fragment over size.\n")); ip_free(qp); - frag_kfree_skb(skb,FREE_WRITE); + kfree_skb(skb,FREE_WRITE); ip_statistics.IpReasmFails++; return NULL; } @@ -466,6 +466,18 @@ return NULL; } } + + /* + * Attempt to construct an oversize packet. + */ + + if(ntohs(iph->tot_len)+(int)offset>65535) + { + skb->sk = NULL; + frag_kfree_skb(skb, FREE_READ); + ip_statistics.IpReasmFails++; + return NULL; + } /* * Determine the position of this fragment. -- --------------BFF22A370E3--
Current thread:
- /usr/bin/solstice under solaris 5.5 Grant Kaufmann (Oct 18)
- Re: /usr/bin/solstice under solaris 5.5 Casper Dik (Oct 19)
- Urgent !! Serious Linux Security Bug.... Jake the Prince (Oct 19)
- Re: Urgent !! Serious Linux Security Bug.... The Cowzilla Man (Oct 19)
- Re: Urgent !! Serious Linux Security Bug.... TriumpH (Oct 20)
- Ping Crashes Erik Fichtner (Oct 22)
- Re: Urgent !! Serious Linux Security Bug.... Kim Alm (Oct 22)
- Re: Urgent !! Serious Linux Security Bug.... Darren Reed (Oct 22)
- <Possible follow-ups>
- /usr/bin/solstice under solaris 5.5 Scriptors of DOOM (Oct 18)