5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> [ Upstream commit a0b39e2dc7017ac667b70bdeee5293e410fab2fb ] nft_counter_reset() resets the counter by subtracting the previously retrieved value from the counter. This is a write operation on the counter and as such it requires to be performed with a write sequence of nft_counter_seq to serialize against its possible reader. Update the packets/ bytes within write-sequence of nft_counter_seq. Fixes: d84701ecbcd6a ("netfilter: nft_counter: rework atomic dump and reset") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Reviewed-by: Florian Westphal <fw@xxxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/netfilter/nft_counter.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/netfilter/nft_counter.c b/net/netfilter/nft_counter.c index f6d4d0fa23a62..bf829fabf2785 100644 --- a/net/netfilter/nft_counter.c +++ b/net/netfilter/nft_counter.c @@ -105,11 +105,16 @@ static void nft_counter_reset(struct nft_counter_percpu_priv *priv, struct nft_counter *total) { struct nft_counter *this_cpu; + seqcount_t *myseq; local_bh_disable(); this_cpu = this_cpu_ptr(priv->counter); + myseq = this_cpu_ptr(&nft_counter_seq); + + write_seqcount_begin(myseq); this_cpu->packets -= total->packets; this_cpu->bytes -= total->bytes; + write_seqcount_end(myseq); local_bh_enable(); } -- 2.43.0