There a two issues with traversal:
1. Key lookup (tree search) cannot detect concurrent modifications and may
not find a result in case of parallel modification.
2. Worker does a lockless iteration. This is never safe.
Add a sequence counter and re-do the lookup under lock in case the
tree was modified / seqcount changed.
gc_worker bugs are addressed in the next patch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Florian Westphal
635a10f6d0