From: Neil Horman <nhorman@tuxdriver.com>
Date: Tue, 11 Jun 2019 07:21:28 -0400

Based on comments from Xin, even after fixes for our recent syzbot
report of cookie memory leaks, its possible to get a resend of an INIT
chunk which would lead to us leaking cookie memory.

To ensure that we don't leak cookie memory, free any previously
allocated cookie first.

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Change notes
v1->v2
update subsystem tag in subject (davem)

Subsystem tag is "sctp: " which still isn't there :-)