[PATCH 5.11 054/210] ethernet/netronome/nfp: Fix a use after free in nfp_bpf_ctrl_msg_rx

Greg Kroah-Hartman
2021-04-12T09:31:10Z

From: Lv Yunlong <lyl2019@mail.ustc.edu.cn>

commit 6e5a03bcba44e080a6bf300194a68ce9bb1e5184 upstream.

In nfp_bpf_ctrl_msg_rx, if
nfp_ccm_get_type(skb) == NFP_CCM_TYPE_BPF_BPF_EVENT is true, the skb
will be freed. But the skb is still used by nfp_ccm_rx(&bpf->ccm, skb).

My patch adds a return when the skb was freed.

Fixes: bcf0cafab44fd ("nfp: split out common control message handling code")
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/netronome/nfp/bpf/cmsg.c | 1 +
1 file changed, 1 insertion(+)

--- a/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/cmsg.c
@@ -454,6 +454,7 @@ void nfp_bpf_ctrl_msg_rx(struct nfp_app
dev_consume_skb_any(skb);
else
dev_kfree_skb_any(skb);
+ return;
}

nfp_ccm_rx(&bpf->ccm, skb);