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Code Execution Bug In Broadcom Wi-Fi Driver
2U*U2 writes to mention an EWeek article about an entry in the Month of Kernel Bugs. John Ellch has discovered a critical vulnerability in the Broadcom wireless driver: a driver used in machines from HP, Dell, Gateway, and eMachines. From the article: "[The bug] is a stack-based buffer overflow in the Broadcom BCMWL5.SYS wireless device driver that could be exploited by attackers to take complete control of a Wi-Fi-enabled laptop. The vulnerability is caused by improper handling of 802.11 probe responses containing a long SSID field and can lead to arbitrary kernel-mode code execution. The volunteer ZERT (Zero Day Emergency Response Team) warns that the flaw could be exploited wirelessly if a vulnerable machine is within range of the attacker."
...the BlackHat presentation this Johnny Cache gave was not just FUD, he really did find bugs in wireless drivers.
There's a discussion about having user space device drivers for usb wireless sticks and some other drivers as well for linux kernel. I hope this kind of attack vectors encourage kernel developers to go in this way. Keeping stuff in user space as much as it allows would again let Linux to be secure-by-design once again. Currently couple of tools (like wpa_supplicant) running in user space, and I wonder their situation in Windows kernel. If they are not (which I guess they are not -because microsoft is known to be putting huge code into kernel level) then that's a huge problem from security perspective.
C is the source of all these problems. Please stop using it.
It's not that simple. C is used in high performance code specifically because it's fast and compact. You get these improvements by avoiding needless length checking. Obviously there are cases where you _do_ need to length check buffers (and exploits are the result of not doing this), but you don't have to length check everything. If you ditch C in favour of a language that does the length checking for you then you will sacrifice speed and compactness since it will be checking _everything_.
What language would you suggest is more suitable for writing high performance kernel code?
http://blog.nexusuk.org