[PATCH 5.16 0380/1039] netfilter: nft_set_pipapo: allocate pcpu scratch maps on clone

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 16:48:17 EST


From: Florian Westphal <fw@xxxxxxxxx>

[ Upstream commit 23c54263efd7cb605e2f7af72717a2a951999217 ]

This is needed in case a new transaction is made that doesn't insert any
new elements into an already existing set.

Else, after second 'nft -f ruleset.txt', lookups in such a set will fail
because ->lookup() encounters raw_cpu_ptr(m->scratch) == NULL.

For the initial rule load, insertion of elements takes care of the
allocation, but for rule reloads this isn't guaranteed: we might not
have additions to the set.

Fixes: 3c4287f62044a90e ("nf_tables: Add set type for arbitrary concatenation of ranges")
Reported-by: etkaar <lists.netfilter.org@xxxxxxx>
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
Reviewed-by: Stefano Brivio <sbrivio@xxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/netfilter/nft_set_pipapo.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c
index dce866d93feed..2c8051d8cca69 100644
--- a/net/netfilter/nft_set_pipapo.c
+++ b/net/netfilter/nft_set_pipapo.c
@@ -1290,6 +1290,11 @@ static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)
if (!new->scratch_aligned)
goto out_scratch;
#endif
+ for_each_possible_cpu(i)
+ *per_cpu_ptr(new->scratch, i) = NULL;
+
+ if (pipapo_realloc_scratch(new, old->bsize_max))
+ goto out_scratch_realloc;

rcu_head_init(&new->rcu);

@@ -1334,6 +1339,9 @@ out_lt:
kvfree(dst->lt);
dst--;
}
+out_scratch_realloc:
+ for_each_possible_cpu(i)
+ kfree(*per_cpu_ptr(new->scratch, i));
#ifdef NFT_PIPAPO_ALIGN
free_percpu(new->scratch_aligned);
#endif
--
2.34.1