Commits
Tom Herbert committed 10e4ea75149
net: Fix race condition in store_rps_map There is a race condition in store_rps_map that allows jump label count in rps_needed to go below zero. This can happen when concurrently attempting to set and a clear map. Scenario: 1. rps_needed count is zero 2. New map is assigned by setting thread, but rps_needed count _not_ yet incremented (rps_needed count still zero) 2. Map is cleared by second thread, old_map set to that just assigned 3. Second thread performs static_key_slow_dec, rps_needed count now goes negative Fix is to increment or decrement rps_needed under the spinlock. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>