Re: [PATCH] mpls, nospec: Sanitize array index in mpls_label_ok()

From: Dan Williams <redacted>
Date: Wed, 07 Feb 2018 22:34:24 -0800

mpls_label_ok() validates that the 'platform_label' array index from a
userspace netlink message payload is valid. Under speculation the
mpls_label_ok() result may not resolve in the CPU pipeline until after
the index is used to access an array element. Sanitize the index to zero
to prevent userspace-controlled arbitrary out-of-bounds speculation, a
precursor for a speculative execution side channel vulnerability.

Cc: <redacted>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric W. Biederman <redacted>
Signed-off-by: Dan Williams <redacted>

Applied, thank you.