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Date:   Wed, 14 Sep 2022 14:07:50 -0700
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Subject: [PATCH v2] staging: rtl8192u: Fix return type of ieee80211_xmit
From:   Nathan Huckleberry <nhuck@google.com>
To:     nhuck@google.com
Cc:     error27@gmail.com, gregkh@linuxfoundation.org,
        linux-kernel@vger.kernel.org, linux-staging@lists.linux.dev,
        llvm@lists.linux.dev, nathan@kernel.org, ndesaulniers@google.com,
        trix@redhat.com
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The ndo_start_xmit field in net_device_ops is expected to be of type
netdev_tx_t (*ndo_start_xmit)(struct sk_buff *skb, struct net_device *dev).

The mismatched return type breaks forward edge kCFI since the underlying
function definition does not match the function hook definition.

The return type of ieee80211_xmit should be changed from int to
netdev_tx_t.

Reported-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/1703
Cc: llvm@lists.linux.dev
Signed-off-by: Nathan Huckleberry <nhuck@google.com>
---

Changes v1 -> v2:
- Updated header file
- Added reviewed-by tag

 drivers/staging/rtl8192u/ieee80211/ieee80211.h    | 2 +-
 drivers/staging/rtl8192u/ieee80211/ieee80211_tx.c | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211.h b/drivers/staging/rtl8192u/ieee80211/ieee80211.h
index b577f9c81f85..9cd4b1896745 100644
--- a/drivers/staging/rtl8192u/ieee80211/ieee80211.h
+++ b/drivers/staging/rtl8192u/ieee80211/ieee80211.h
@@ -2178,7 +2178,7 @@ int ieee80211_set_encryption(struct ieee80211_device *ieee);
 int ieee80211_encrypt_fragment(struct ieee80211_device *ieee,
 			       struct sk_buff *frag, int hdr_len);
 
-int ieee80211_xmit(struct sk_buff *skb, struct net_device *dev);
+netdev_tx_t ieee80211_xmit(struct sk_buff *skb, struct net_device *dev);
 void ieee80211_txb_free(struct ieee80211_txb *txb);
 
 
diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211_tx.c b/drivers/staging/rtl8192u/ieee80211/ieee80211_tx.c
index 8602e3a6c837..e4b6454809a0 100644
--- a/drivers/staging/rtl8192u/ieee80211/ieee80211_tx.c
+++ b/drivers/staging/rtl8192u/ieee80211/ieee80211_tx.c
@@ -526,7 +526,7 @@ static void ieee80211_query_seqnum(struct ieee80211_device *ieee,
 	}
 }
 
-int ieee80211_xmit(struct sk_buff *skb, struct net_device *dev)
+netdev_tx_t ieee80211_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct ieee80211_device *ieee = netdev_priv(dev);
 	struct ieee80211_txb *txb = NULL;
@@ -822,13 +822,13 @@ int ieee80211_xmit(struct sk_buff *skb, struct net_device *dev)
 			if ((*ieee->hard_start_xmit)(txb, dev) == 0) {
 				stats->tx_packets++;
 				stats->tx_bytes += __le16_to_cpu(txb->payload_size);
-				return 0;
+				return NETDEV_TX_OK;
 			}
 			ieee80211_txb_free(txb);
 		}
 	}
 
-	return 0;
+	return NETDEV_TX_OK;
 
  failed:
 	spin_unlock_irqrestore(&ieee->lock, flags);
-- 
2.37.2.789.g6183377224-goog