From owner-freebsd-net@freebsd.org  Wed Oct 21 14:59:54 2015
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Date: Wed, 21 Oct 2015 16:50:08 +0200 (CEST)
From: elof2@sentor.se
To: freebsd-net <freebsd-net@freebsd.org>
Subject: sysctl and signed net.bpf.maxbufsize variable
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Isn't this a bug?

# sysctl net.bpf.maxbufsize=3000000000
net.bpf.maxbufsize: 524288 -> -1294967296

No error message and exit status is 0.


Shouldn't net.bpf.maxbufsize be unsigned?



I would like sysctl to have a crude sanity control and return an error if 
you set a positive value but the result becomes negative.


...and also have some specific sanity control to test if you try to set a 
value waaaay out of bounds (like setting net.bpf.maxbufsize to a value greater 
than the maximum RAM).

/Elof