6.6-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 5a90c3c7268bf..b7aa4d2c8c22f 100644
--- a/net/netfilter/nft_counter.c
+++ b/net/netfilter/nft_counter.c
@@ -107,11 +107,16 @@ 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
