glibc getaddrinfo() stack overflow

[Nytro]

glibc getaddrinfo() stack overflow

From: Marcus Meissner <meissner () suse de>

Date: Wed, 3 Apr 2013 13:10:21 +0200

Hi,

A customer reported a glibc crash, which turned out to be a stack overflow in

getaddrinfo().

getaddrinfo() uses:

struct sort_result results[nresults];

with nresults controlled by the nameservice chain (DNS or /etc/hosts).

This will be visible mostly on threaded applications with smaller stacksizes,

or operating near out of stack.

Reproducer I tried:

$ for i in `seq 1 10000000`; do echo "ff00::$i a1" >>/etc/hosts; done

$ ulimit -s 1024

$ telnet a1

Segmentation fault

(clean out /etc/hosts again )

I am not sure you can usually push this amount of addresses via DNS for all

setups.

Andreas is currently pushing the patch to glibc GIT.

Reference:

https://bugzilla.novell.com/show_bug.cgi?id=813121

Ciao, Marcus

Sursa: oss-sec: CVE Request: glibc getaddrinfo() stack overflow