From 936206e3f6ff411581e615e930263d6f8b78df9d Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 7 Apr 2026 17:00:01 +0200 Subject: netfilter: nfnetlink_queue: make hash table per queue Sharing a global hash table among all queues is tempting, but it can cause crash: BUG: KASAN: slab-use-after-free in nfqnl_recv_verdict+0x11ac/0x15e0 [nfnetlink_queue] [..] nfqnl_recv_verdict+0x11ac/0x15e0 [nfnetlink_queue] nfnetlink_rcv_msg+0x46a/0x930 kmem_cache_alloc_node_noprof+0x11e/0x450 struct nf_queue_entry is freed via kfree, but parallel cpu can still encounter such an nf_queue_entry when walking the list. Alternative fix is to free the nf_queue_entry via kfree_rcu() instead, but as we have to alloc/free for each skb this will cause more mem pressure. Cc: Scott Mitchell Fixes: e19079adcd26 ("netfilter: nfnetlink_queue: optimize verdict lookup with hash table") Signed-off-by: Florian Westphal --- include/net/netfilter/nf_queue.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include') diff --git a/include/net/netfilter/nf_queue.h b/include/net/netfilter/nf_queue.h index 45eb26b2e95b..d17035d14d96 100644 --- a/include/net/netfilter/nf_queue.h +++ b/include/net/netfilter/nf_queue.h @@ -23,7 +23,6 @@ struct nf_queue_entry { struct nf_hook_state state; bool nf_ct_is_unconfirmed; u16 size; /* sizeof(entry) + saved route keys */ - u16 queue_num; /* extra space to store route keys */ }; -- cgit v1.2.3