This is a note to let you know that I've just added the patch titled netfilter: nf_tables: fix null deref due to zeroed list head to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: netfilter-nf_tables-fix-null-deref-due-to-zeroed-list-head.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 580077855a40741cf511766129702d97ff02f4d9 Mon Sep 17 00:00:00 2001 From: Florian Westphal <fw@xxxxxxxxx> Date: Tue, 9 Aug 2022 18:34:02 +0200 Subject: netfilter: nf_tables: fix null deref due to zeroed list head From: Florian Westphal <fw@xxxxxxxxx> commit 580077855a40741cf511766129702d97ff02f4d9 upstream. In nf_tables_updtable, if nf_tables_table_enable returns an error, nft_trans_destroy is called to free the transaction object. nft_trans_destroy() calls list_del(), but the transaction was never placed on a list -- the list head is all zeroes, this results in a null dereference: BUG: KASAN: null-ptr-deref in nft_trans_destroy+0x26/0x59 Call Trace: nft_trans_destroy+0x26/0x59 nf_tables_newtable+0x4bc/0x9bc [..] Its sane to assume that nft_trans_destroy() can be called on the transaction object returned by nft_trans_alloc(), so make sure the list head is initialised. Fixes: 55dd6f93076b ("netfilter: nf_tables: use new transaction infrastructure to handle table") Reported-by: mingi cho <mgcho.minic@xxxxxxxxx> Signed-off-by: Florian Westphal <fw@xxxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/netfilter/nf_tables_api.c | 1 + 1 file changed, 1 insertion(+) --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -114,6 +114,7 @@ static struct nft_trans *nft_trans_alloc if (trans == NULL) return NULL; + INIT_LIST_HEAD(&trans->list); trans->msg_type = msg_type; trans->ctx = *ctx; Patches currently in stable-queue which might be from fw@xxxxxxxxx are queue-5.10/netfilter-nf_tables-fix-null-deref-due-to-zeroed-list-head.patch