Re: [syzbot] [PATCH net] nfc: nci: Fix uninit-value in nci_dev_up

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Subject: [PATCH net] nfc: nci: Fix uninit-value in nci_dev_up
Author: ryasuoka@xxxxxxxxxx

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 9f8413c4a66f2fb776d3dc3c9ed20bf435eb305e

diff --git a/net/nfc/nci/ntf.c b/net/nfc/nci/ntf.c
index 994a0a1efb58..efdd733fc676 100644
--- a/net/nfc/nci/ntf.c
+++ b/net/nfc/nci/ntf.c
@@ -759,6 +759,9 @@ void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb)
 {
 	__u16 ntf_opcode = nci_opcode(skb->data);
 
+	if (unlikely(!nci_plen(skb->data)))
+		goto end;
+
 	pr_debug("NCI RX: MT=ntf, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n",
 		 nci_pbf(skb->data),
 		 nci_opcode_gid(ntf_opcode),