Re: [syzbot] [PATCH] Test for aea6bf908d73

[syzbot <syzbot+bbe84a4010eeea00982d@syzkaller.appspotmail.com>]

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Subject: [PATCH] Test for aea6bf908d73
Author: eadavis@qq.com

please test uaf in nfc_alloc_send_skb

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git aea6bf908d73

diff --git a/net/nfc/llcp_core.c b/net/nfc/llcp_core.c
index 1dac28136e6a..016364890357 100644
--- a/net/nfc/llcp_core.c
+++ b/net/nfc/llcp_core.c
@@ -1640,11 +1640,14 @@ int nfc_llcp_register_device(struct nfc_dev *ndev)
 void nfc_llcp_unregister_device(struct nfc_dev *dev)
 {
 	struct nfc_llcp_local *local = nfc_llcp_remove_local(dev);
+	struct nfc_llcp_sock *nls;
 
 	if (local == NULL) {
 		pr_debug("No such device\n");
 		return;
 	}
+	nls = container_of(local, struct nfc_llcp_sock, local);
+	nls->local = NULL;
 
 	local_cleanup(local);