[PATCH 4.4 17/44] nfc: fix error handling of nfc_proto_register()

[Greg Kroah-Hartman]

From: Ziyang Xuan <william.xuanziyang@xxxxxxxxxx>

commit 0911ab31896f0e908540746414a77dd63912748d upstream.

When nfc proto id is using, nfc_proto_register() return -EBUSY error
code, but forgot to unregister proto. Fix it by adding proto_unregister()
in the error handling case.

Fixes: c7fe3b52c128 ("NFC: add NFC socket family")
Signed-off-by: Ziyang Xuan <william.xuanziyang@xxxxxxxxxx>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20211013034932.2833737-1-william.xuanziyang@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/nfc/af_nfc.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/net/nfc/af_nfc.c
+++ b/net/nfc/af_nfc.c
@@ -72,6 +72,9 @@ int nfc_proto_register(const struct nfc_
 		proto_tab[nfc_proto->id] = nfc_proto;
 	write_unlock(&proto_tab_lock);
 
+	if (rc)
+		proto_unregister(nfc_proto->proto);
+
 	return rc;
 }
 EXPORT_SYMBOL(nfc_proto_register);