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

[syzbot <syzbot+7ea9413ea6749baf5574@syzkaller.appspotmail.com>]

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

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

diff --git a/net/nfc/nci/ntf.c b/net/nfc/nci/ntf.c
index 994a0a1efb58..56624387e253 100644
--- a/net/nfc/nci/ntf.c
+++ b/net/nfc/nci/ntf.c
@@ -765,6 +765,9 @@ void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb)
 		 nci_opcode_oid(ntf_opcode),
 		 nci_plen(skb->data));
 
+	if (!nci_plen(skb->data))
+		goto end;
+
 	/* strip the nci control header */
 	skb_pull(skb, NCI_CTRL_HDR_SIZE);