wither bounds checking for networking sysctls

While messing about with "sysctl_tcp_rto_min" I went back and forth a 
bit as to whether there should have been bounds checking (as did some of 
the folks who did some internal review for me).  That leads to the 
question - is it considered worthwhile to add a bit more bounds checking 
to sundry networking sysctls?

rick jones

On Thu, 30 Aug 2007 18:09:17 -0700
Rick Jones [off-list ref] wrote:

While messing about with "sysctl_tcp_rto_min" I went back and forth a 
bit as to whether there should have been bounds checking (as did some of 
the folks who did some internal review for me).  That leads to the 
question - is it considered worthwhile to add a bit more bounds checking 
to sundry networking sysctls?

rick jones

IMHO As long as the any value from sysctl doesn't crash kernel, we
should let it go. Enforcing RFC policy or inter-dependencies seems
likes a useless exercise.

Stephen Hemminger wrote:

On Thu, 30 Aug 2007 18:09:17 -0700
Rick Jones [off-list ref] wrote:

quoted

While messing about with "sysctl_tcp_rto_min" I went back and forth a 
bit as to whether there should have been bounds checking (as did some of 
the folks who did some internal review for me).  That leads to the 
question - is it considered worthwhile to add a bit more bounds checking 
to sundry networking sysctls?

rick jones

IMHO As long as the any value from sysctl doesn't crash kernel, we
should let it go. Enforcing RFC policy or inter-dependencies seems
likes a useless exercise.

I was thinking more along the lines of more fundamental things - like 
precluding negative values when something is clearly a positive.

rick jones

Rick Jones [off-list ref] writes:

Stephen Hemminger wrote:

quoted

On Thu, 30 Aug 2007 18:09:17 -0700
Rick Jones [off-list ref] wrote:

quoted

While messing about with "sysctl_tcp_rto_min" I went back and forth a bit as
to whether there should have been bounds checking (as did some of the folks
who did some internal review for me).  That leads to the question - is it
considered worthwhile to add a bit more bounds checking to sundry networking
sysctls?

rick jones

IMHO As long as the any value from sysctl doesn't crash kernel, we
should let it go. Enforcing RFC policy or inter-dependencies seems
likes a useless exercise.

I was thinking more along the lines of more fundamental things - like precluding
negative values when something is clearly a positive.

The sysctl infrastructure has some fairly simple support for
doing min/max type things.  So if it makes sense it isn't hard to
make proc_dointvec_minmax the method and then set extra1 to point to
the min and extra2 to be the max. 

Eric