Linux Study Argues Monolithic OS Design Leads To Critical Exploits (osnews.com)
Long-time Slashdot reader Mike Bouma shares a paper (via OS News) making the case for "a small microkernel as the core of the trusted computing base, with OS services separated into mutually-protected components (servers) -- in contrast to 'monolithic' designs such as Linux, Windows or MacOS."
While intuitive, the benefits of the small trusted computing base have not been quantified to date. We address this by a study of critical Linux CVEs [PDF] where we examine whether they would be prevented or mitigated by a microkernel-based design. We find that almost all exploits are at least mitigated to less than critical severity, and 40% completely eliminated by an OS design based on a verified microkernel, such as seL4....
Our results provide very strong evidence that operating system structure has a strong effect on security. 96% of critical Linux exploits would not reach critical severity in a microkernel-based system, 57% would be reduced to low severity, the majority of which would be eliminated altogether if the system was based on a verified microkernel. Even without verification, a microkernel-based design alone would completely prevent 29% of exploits...
The conclusion is inevitable: From the security point of view, the monolithic OS design is flawed and a root cause of the majority of compromises. It is time for the world to move to an OS structure appropriate for 21st century security requirements.
Our results provide very strong evidence that operating system structure has a strong effect on security. 96% of critical Linux exploits would not reach critical severity in a microkernel-based system, 57% would be reduced to low severity, the majority of which would be eliminated altogether if the system was based on a verified microkernel. Even without verification, a microkernel-based design alone would completely prevent 29% of exploits...
The conclusion is inevitable: From the security point of view, the monolithic OS design is flawed and a root cause of the majority of compromises. It is time for the world to move to an OS structure appropriate for 21st century security requirements.
He was right then. At the time CPUs were slow. Now we have pretty fast CPUs, faster than most people need. The overhead for a microkernel isn't so bad now.
Don't let your ignorance get in the way of your mouth, either.
Having spent several thousand hours of my life dredging through Darwin's kernel interfaces, I can tell you the beating heart of Mach, the actual microkernel inside of MacOS, is literally dwarfed by the monstrous amounts of monolithic BSD and Mac bolt-ons.
In the end, I found the Mach aspect of Darwin served little purpose beyond making it more annoying to work in that Kernel. It sure didn't slow me down in my task of modifying the Kernel's page tables from user-space on an iPhone.
I love it when people who have no idea what they're talking about make such confident assertions.