CVE-2010-4249: Medium severity Linux Linux kernel vulnerability
http://lkml.org/lkml/2010/11/23/395
Reported by Vegard Nossum: "I found this program lying around on my laptop. It kills my box (2.6.35) instantly by consuming a lot of memory (allocated by the kernel, so the process doesn't get killed by the OOM killer). As far as I can tell, the memory isn't being freed when the program exits either. Maybe it will eventually get cleaned up the UNIX socket garbage collector thing, but in that case it doesn't get called quickly enough to save my machine at least."
Reproducer: http://lkml.org/lkml/2010/11/23/395 Partial fix: http://lkml.org/lkml/2010/11/23/450 Remaining fix: http://marc.info/?l=linux-netdev&m=129059035929046&w=2
From Eric Dumazet: "we can eat all LOWMEM memory before unixgc() being called from unixreleasesock(). Moreover, the thread blocked in unixgc() can consume huge amount of time to perform cleanup because of huge working set.
One way to handle this is to have a sensible limit on unixtotinflight, tested from waitforunixgc() and to force a call to unixgc() if this limit is hit.
This solves the OOM and also reduce overall latencies, and should not slowdown normal workloads."
Acknowledgements:
Red Hat would like to thank Vegard Nossum for reporting this issue.
Other sources
The waitforunixgc function in net/unix/garbage.c in the Linux kernel before 2.6.37-rc3-next-20101125 does not properly select times for garbage collection of inflight sockets, which allows local users to cause a denial of service (system hang) via crafted use of the socketpair and sendmsg system calls for SOCKSEQPACKET sockets.
— Launchpad
Affected Software
Remediation
Patch Available
Patch Available
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Event History
Frequently Asked Questions
What is the severity of CVE-2010-4249?
CVE-2010-4249 is classified as a high severity vulnerability due to its potential to crash systems by consuming excessive memory.
Which Linux kernel versions are affected by CVE-2010-4249?
CVE-2010-4249 affects Linux kernel versions prior to 2.6.37, including the 2.6.35 version.
How do I fix CVE-2010-4249?
To resolve CVE-2010-4249, upgrade to at least Linux kernel version 2.6.37 or later.
What types of systems are vulnerable to CVE-2010-4249?
CVE-2010-4249 impacts systems running affected Linux kernel versions, including certain Debian and Fedora distributions.
What impact does CVE-2010-4249 have on a system?
CVE-2010-4249 can cause a denial of service by consuming a significant amount of memory, leading to system crashes.