[kevincox]

It is quite possible that Linux is the bigger target so it gets more focus. Vulnerabilities there are generally considered more valuable and notable. It would be very difficult to use these numbers to get a meaningful "more secure" stance as there are tons of variables.

[t-3]

From a quick search, Linux kernel is ~40 million loc, freebsd ~9 million, openbsd ~3 million. Number of bugs compared to lines of code leaves FreeBSD looking worse than Linux.

[mikem170]

I assume those are lines of code in just the kernels.

As an FYI to everyone: The OpenBSD and FreeBSD teams both maintain entire distributions, similar to Linux + Debian or Linux + Redhat. The OpenBSD team also owns a number of other projects - everything from OpenSSH to PF, OpenBGPD, OpenNTPD, OpenSMTPD, OpenIKED, LibreSSL, pledge and unveil, their own set of perl patches, etc.

I'd say that less lines of code seems to correlate with less bugs in absolute numbers, which works out as more secure for those who don't need the extra code.

[acdha]

Linux also has a ton of extra functionality so I think you’d also have to do some adjustment for “as a user would I be at risk?” versus “can I be a user because it supports my needs?” Some of that would be unfavorable for many users (e.g. a Linux user who is exposed due to a network protocol or file system they’ll never use) but that’s certainly not true of every feature.

[yjftsjthsd-h]

That cuts both ways, though. If the functionality is present by default but I'm not using it, that's just extra vulnerability surface. (Of course, if I do want that feature, then its absence is kinda a problem)

[acdha]

Hence the second sentence.

[hulitu]

Linux also has a ton of bloat. Configuring your own kernel has become an exercise in frustration because documentation is worse "There is no help for this kernel option" and a lot of things are enabled "by default".

[acdha]

Yes, that’s why I wrote the second sentence. However, it’s quite an exaggeration that it’s super hard to configure a kernel - distributions can do that for you (e.g. Amazon Linux disabled a bunch of drivers for hardware you’ll never have in EC2), modules can easily be disabled (common remediation for those IPsec accelerators earlier this year), and it’s not that hard to build your own kernels and distribute them on most popular distributions.

[dspillett]

If this is just counting the kernel, than Linux is probably a bigger target both i terms of current code size and the amount of churn in the codebase as things change over time. Some of the LPEs might (I've not checked) be in modules that are not commonly loaded, which mitigates their overall significance somewhat.

In the less likely even that this is counting what laymen would call Linux or BSD, i.e. both the kernel and common libraries & tools, then Linux definitely has a wider attack surface. Though some of that surface is shared as some userland parts are common to both.

As with your assessment, I'd agree that these flat numbers without looking for further context don't really give enough for a one-is-more-or-less-secure statement.