Re: [PATCH v2 1/1] net: netlink: Fix multicast group storage allocation for families with more than one groups

[David Miller]

From: Matti Vaittinen <matti.vaittinen@xxxxxxxxx>
Date: Wed, 13 Jan 2016 09:54:12 +0200

> Hello again,
> 
>       Second version, Fixed the 'off by one' bug spotted by David.
> 
>       Br.
>         Matti Vaittinen
> 
> Multicast groups are stored in global buffer. Check for needed buffer size
> incorrectly compares buffer size to first id for family. This means that
> for families with more than one mcast id one may allocate too small buffer
> and end up writing rest of the groups to some unallocated memory. Fix the
> buffer size check to compare allocated space to last mcast id for the
> family.
> 
> Tested on ARM using kernel 3.14
> 
> Signed-off-by: Matti Vaittinen <matti.vaittinen@xxxxxxxxx>

I inadvertantly applied your original patch, so I'll just fix
the off-by-one error with a seperate commit.

Sorry for the confusion and thanks for fixing this.