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 @@ -119,6 +119,7 @@ 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;