Re: [PATCH net] ptp: limit number of virtual clocks per physical clock

[Paolo Abeni]

On 1/3/25 2:40 PM, Thomas Weißschuh wrote:
> The sysfs interface can be used to trigger arbitrarily large memory
> allocations. This can induce pressure on the VM layer to satisfy the
> request only to fail anyways.
> 
> Reported-by: cheung wall <zzqq0103.hey@xxxxxxxxx>
> Closes: https://lore.kernel.org/lkml/20250103091906.GD1977892@ZenIV/
> Fixes: 73f37068d540 ("ptp: support ptp physical/virtual clocks conversion")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> ---
> The limit is completely made up, let me know if there is something
> better.

I'm also unsure if such constant value is reasonable for all the
use-cases. Any additional feedback more than welcome.

In any case, I guess it would make sense to update
Documentation/ABI/testing/sysfs-ptp accordingly.

Thanks,

Paolo