netfilter: nf_tables: fix module unload race
We must first remove the nfnetlink protocol handler when nf_tables module is unloaded -- we don't want userspace to submit new change requests once we've started to tear down nft state. Furthermore, nfnetlink must not call any subsystem function after call_batch returned -EAGAIN. EAGAIN means the subsys mutex was dropped, so its unlikely but possible that nf_tables subsystem was removed due to 'rmmod nf_tables' on another cpu. Therefore, we must abort batch completely and not move on to next part of the batch. Last, we can't invoke ->abort unless we've checked that the subsystem is still registered. Change netns exit path of nf_tables to make sure any incompleted transaction gets removed on exit. Signed-off-by:Florian Westphal <fw@strlen.de> Signed-off-by:
Pablo Neira Ayuso <pablo@netfilter.org>
parent
215a31f1
Please register or sign in to comment