Where is the documentation for net.ipv4.conf.all.log_martians?

Question

Where is the documentation for net.ipv4.conf.all.log_martians sysctl setting? There are man pages for various other TCP/IP/UDP (man 7 tcp, man 7 upd, man 7 ip) settings, but I can't find the net.ipv4.conf.all.log_martians docs.

Note: I want official documentation from Linux; not random sites from google.

Solution

Things you find in the man pages are generally about programming, and the C API. Non-programming documentation is generally found in the kernel itself.

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/networking/ip-sysctl.txt?id=bb077d600689dbf9305758efed1e16775db1c84c#n843

And those random google sites aren't usually wrong. I'm sure you'll find that many of them are just online versions of the kernel documentation.