[PATCH] Staging: rtl8192e: Fix return type of rtllib_xmit

[PATCH] Staging: rtl8192e: Fix return type of rtllib_xmit

[Nathan Huckleberry]

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 rtllib_xmit should be changed from int to
netdev_tx_t.

Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1703
Cc: llvm@lists.linux.dev
Signed-off-by: Nathan Huckleberry <nhuck@google.com>
---
 drivers/staging/rtl8192e/rtllib_tx.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/rtl8192e/rtllib_tx.c b/drivers/staging/rtl8192e/rtllib_tx.c
index 42f81b23a144..1b665afd309e 100644
--- a/drivers/staging/rtl8192e/rtllib_tx.c
+++ b/drivers/staging/rtl8192e/rtllib_tx.c
@@ -543,7 +543,7 @@ static u8 rtllib_current_rate(struct rtllib_device *ieee)
 		return ieee->rate & 0x7F;
 }
 
-static int rtllib_xmit_inter(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t rtllib_xmit_inter(struct sk_buff *skb, struct net_device *dev)
 {
 	struct rtllib_device *ieee = (struct rtllib_device *)
 				     netdev_priv_rsl(dev);
@@ -946,13 +946,13 @@ static int rtllib_xmit_inter(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;
 			}
 			rtllib_txb_free(txb);
 		}
 	}
 
-	return 0;
+	return NETDEV_TX_OK;
 
  failed:
 	spin_unlock_irqrestore(&ieee->lock, flags);
@@ -962,7 +962,7 @@ static int rtllib_xmit_inter(struct sk_buff *skb, struct net_device *dev)
 
 }
 
-int rtllib_xmit(struct sk_buff *skb, struct net_device *dev)
+netdev_tx_t rtllib_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	memset(skb->cb, 0, sizeof(skb->cb));
 	return rtllib_xmit_inter(skb, dev);
-- 
2.37.2.789.g6183377224-goog

Re: [PATCH] Staging: rtl8192e: Fix return type of rtllib_xmit

[Philipp Hortmann]

On 9/12/22 23:45, 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 rtllib_xmit should be changed from int to
> netdev_tx_t.
> 
> Reported-by: Dan Carpenter<error27@gmail.com>
> Link:https://github.com/ClangBuiltLinux/linux/issues/1703
> Cc:llvm@lists.linux.dev
> Signed-off-by: Nathan Huckleberry<nhuck@google.com>
> ---
>   drivers/staging/rtl8192e/rtllib_tx.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/staging/rtl8192e/rtllib_tx.c b/drivers/staging/rtl8192e/rtllib_tx.c
> index 42f81b23a144..1b665afd309e 100644
> --- a/drivers/staging/rtl8192e/rtllib_tx.c
> +++ b/drivers/staging/rtl8192e/rtllib_tx.c

Hi,

I cannot apply your patch.

Applying: Staging: rtl8192e: Fix return type of rtllib_xmit
error: patch failed: drivers/staging/rtl8192e/rtllib_tx.c:962
error: drivers/staging/rtl8192e/rtllib_tx.c: patch does not apply
Patch failed at 0001 Staging: rtl8192e: Fix return type of rtllib_xmit

git remote show origin
* remote origin
   Fetch URL: 
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
...
my branch: staging-testing

Bye Philipp

Re: [PATCH] Staging: rtl8192e: Fix return type of rtllib_xmit

[Nathan Huckleberry]

Looks like this has already been fixed in commit
513d9a61156d79dd0979c4ad400c8587f52cbb9d

On Tue, Sep 13, 2022 at 11:48 AM Philipp Hortmann
<philipp.g.hortmann@gmail.com> wrote:
>
> On 9/12/22 23:45, 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 rtllib_xmit should be changed from int to
> > netdev_tx_t.
> >
> > Reported-by: Dan Carpenter<error27@gmail.com>
> > Link:https://github.com/ClangBuiltLinux/linux/issues/1703
> > Cc:llvm@lists.linux.dev
> > Signed-off-by: Nathan Huckleberry<nhuck@google.com>
> > ---
> >   drivers/staging/rtl8192e/rtllib_tx.c | 8 ++++----
> >   1 file changed, 4 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/staging/rtl8192e/rtllib_tx.c b/drivers/staging/rtl8192e/rtllib_tx.c
> > index 42f81b23a144..1b665afd309e 100644
> > --- a/drivers/staging/rtl8192e/rtllib_tx.c
> > +++ b/drivers/staging/rtl8192e/rtllib_tx.c
>
> Hi,
>
> I cannot apply your patch.
>
> Applying: Staging: rtl8192e: Fix return type of rtllib_xmit
> error: patch failed: drivers/staging/rtl8192e/rtllib_tx.c:962
> error: drivers/staging/rtl8192e/rtllib_tx.c: patch does not apply
> Patch failed at 0001 Staging: rtl8192e: Fix return type of rtllib_xmit
>
> git remote show origin
> * remote origin
>    Fetch URL:
> git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
> ...
> my branch: staging-testing
>
> Bye Philipp