[PATCH 5.15 245/245] netfilter: nf_tables: cant schedule in nft_chain_validate

Greg Kroah-Hartman
2024-02-27T14:12:31Z

From: Florian Westphal <fw@strlen.de>

commit 314c82841602a111c04a7210c21dc77e0d560242 upstream.

Can be called via nft set element list iteration, which may acquire
rcu and/or bh read lock (depends on set type).

BUG: sleeping function called from invalid context at net/netfilter/nf_tables_api.c:3353
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 1232, name: nft
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
2 locks held by nft/1232:
#0: ffff8881180e3ea8 (&nft_net->commit_mutex){+.+.}-{3:3}, at: nf_tables_valid_genid
#1: ffffffff83f5f540 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire
Call Trace:
nft_chain_validate
nft_lookup_validate_setelem
nft_pipapo_walk
nft_lookup_validate
nft_chain_validate
nft_immediate_validate
nft_chain_validate
nf_tables_validate
nf_tables_abort

No choice but to move it to nf_tables_validate().

Fixes: 81ea01066741 ("netfilter: nf_tables: add rescheduling points during loop detection walks")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/netfilter/nf_tables_api.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3443,8 +3443,6 @@ int nft_chain_validate(const struct nft_
if (err < 0)
return err;
}
-
- cond_resched();
}

return 0;
@@ -3468,6 +3466,8 @@ static int nft_table_validate(struct net
err = nft_chain_validate(&ctx, chain);
if (err < 0)
return err;
+
+ cond_resched();
}

return 0;