Re: [PATCH v3] staging: r8188eu: Fix return type of rtw_xmit_entry

From: Philipp Hortmann
Date: Thu Sep 15 2022 - 01:23:02 EST


On 9/14/22 23:16, Nathan Huckleberry wrote:
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 rtw_xmit_entry should be changed from int to
netdev_tx_t.

Reported-by: Dan Carpenter <error27@xxxxxxxxx>
Link: https://github.com/ClangBuiltLinux/linux/issues/1703
Cc: llvm@xxxxxxxxxxxxxxx
Signed-off-by: Nathan Huckleberry <nhuck@xxxxxxxxxx>
Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
---

Changes v1 -> v2:
- Rebased onto linux-next/master

Changes v2 -> v3:
- Updated header file
- Add reviewed-by tag

drivers/staging/r8188eu/core/rtw_xmit.c | 4 ++--
drivers/staging/r8188eu/include/rtw_xmit.h | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/r8188eu/core/rtw_xmit.c b/drivers/staging/r8188eu/core/rtw_xmit.c
index 98864fc55b25..ea13f11b231b 100644
--- a/drivers/staging/r8188eu/core/rtw_xmit.c
+++ b/drivers/staging/r8188eu/core/rtw_xmit.c
@@ -2289,7 +2289,7 @@ static int rtw_mlcst2unicst(struct adapter *padapter, struct sk_buff *skb)
return true;
}
-int rtw_xmit_entry(struct sk_buff *pkt, struct net_device *pnetdev)
+netdev_tx_t rtw_xmit_entry(struct sk_buff *pkt, struct net_device *pnetdev)
{
struct adapter *padapter = (struct adapter *)rtw_netdev_priv(pnetdev);
struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
@@ -2323,5 +2323,5 @@ int rtw_xmit_entry(struct sk_buff *pkt, struct net_device *pnetdev)
dev_kfree_skb_any(pkt);
exit:
- return 0;
+ return NETDEV_TX_OK;
}
diff --git a/drivers/staging/r8188eu/include/rtw_xmit.h b/drivers/staging/r8188eu/include/rtw_xmit.h
index 8f54c41ba927..82efcd54af3f 100644
--- a/drivers/staging/r8188eu/include/rtw_xmit.h
+++ b/drivers/staging/r8188eu/include/rtw_xmit.h
@@ -368,6 +368,6 @@ int rtw_ack_tx_wait(struct xmit_priv *pxmitpriv, u32 timeout_ms);
void rtw_ack_tx_done(struct xmit_priv *pxmitpriv, int status);
void rtw_xmit_complete(struct adapter *padapter, struct xmit_frame *pxframe);
-int rtw_xmit_entry(struct sk_buff *pkt, struct net_device *pnetdev);
+netdev_tx_t rtw_xmit_entry(struct sk_buff *pkt, struct net_device *pnetdev);
#endif /* _RTL871X_XMIT_H_ */

Tested-by: Philipp Hortmann <philipp.g.hortmann@xxxxxxxxx> # Edimax N150