On 10/02/2017 09:20 PM, Eric Dumazet wrote:
From: Eric Dumazet <[email protected]>Starting from linux-4.4, 3WHS no longer takes the listener lock. Since this time, we might hit a use-after-free in sk_filter_charge(), if the filter we got in the memcpy() of the listener content just happened to be replaced by a thread changing listener BPF filter. To fix this, we need to make sure the filter refcount is not already zero before incrementing it again. Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") Signed-off-by: Eric Dumazet <[email protected]>
Thanks, Eric! Acked-by: Daniel Borkmann <[email protected]>
