diff mbox series

[1/6,next] orinoco: Avoid clashing function prototypes

Message ID 2387e02ae7f31388f24041cae8d02d5e12151708.1666038048.git.gustavoars@kernel.org
State New
Headers
Series Avoid clashing function prototypes |

Commit Message

Gustavo A. R. Silva Oct. 17, 2022, 8:33 p.m. UTC 
  When built with Control Flow Integrity, function prototypes between
caller and function declaration must match. These mismatches are visible
at compile time with the new -Wcast-function-type-strict in Clang[1].

Fix a total of 53 warnings like these:

drivers/net/wireless/intersil/orinoco/wext.c:1379:27: warning: cast from 'int (*)(struct net_device *, struct iw_request_info *, struct iw_param *, char *)' to 'iw_handler' (aka 'int (*)(struct net_device *, struct iw_request_info *, union iwreq_data *, char *)') converts to incompatible function type [-Wcast-function-type-strict]
        IW_HANDLER(SIOCGIWPOWER,        (iw_handler)orinoco_ioctl_getpower),
                                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

../net/wireless/wext-compat.c:1607:33: warning: cast from 'int (*)(struct net_device *, struct iw_request_info *, struct iw_point *, char *)' to 'iw_handler' (aka 'int (*)(struct net_device *, struct iw_request_info *, union iwreq_data *, char *)') converts to incompatible function type [-Wcast-function-type-strict]
        [IW_IOCTL_IDX(SIOCSIWGENIE)]    = (iw_handler) cfg80211_wext_siwgenie,
                                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The orinoco Wireless Extension handler callbacks (iw_handler) use a
union for the data argument. Actually use the union and perform explicit
member selection in the function body instead of having a function
prototype mismatch. No significant binary differences were seen
before/after changes.

Link: https://github.com/KSPP/linux/issues/234
Link: https://reviews.llvm.org/D134831 [1]
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
 drivers/net/wireless/intersil/orinoco/wext.c | 109 +++++++++++--------
 1 file changed, 62 insertions(+), 47 deletions(-)

Comments

Kees Cook Oct. 18, 2022, 2:26 a.m. UTC | #1 
On Mon, Oct 17, 2022 at 03:33:01PM -0500, Gustavo A. R. Silva wrote:
> When built with Control Flow Integrity, function prototypes between
> caller and function declaration must match. These mismatches are visible
> at compile time with the new -Wcast-function-type-strict in Clang[1].
> 
> Fix a total of 53 warnings like these:
> 
> drivers/net/wireless/intersil/orinoco/wext.c:1379:27: warning: cast from 'int (*)(struct net_device *, struct iw_request_info *, struct iw_param *, char *)' to 'iw_handler' (aka 'int (*)(struct net_device *, struct iw_request_info *, union iwreq_data *, char *)') converts to incompatible function type [-Wcast-function-type-strict]
>         IW_HANDLER(SIOCGIWPOWER,        (iw_handler)orinoco_ioctl_getpower),
>                                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> ../net/wireless/wext-compat.c:1607:33: warning: cast from 'int (*)(struct net_device *, struct iw_request_info *, struct iw_point *, char *)' to 'iw_handler' (aka 'int (*)(struct net_device *, struct iw_request_info *, union iwreq_data *, char *)') converts to incompatible function type [-Wcast-function-type-strict]
>         [IW_IOCTL_IDX(SIOCSIWGENIE)]    = (iw_handler) cfg80211_wext_siwgenie,
>                                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Thank you for working on these! Was this conversion done manually, via
coccinelle, or something else?

> The orinoco Wireless Extension handler callbacks (iw_handler) use a
> union for the data argument. Actually use the union and perform explicit
> member selection in the function body instead of having a function
> prototype mismatch. No significant binary differences were seen
> before/after changes.

What does "significant" mean here? :P Anything related to line counts
can just be ignored. But I'd expect the .text output of
drivers/net/wireless/intersil/orinoco/wext.o before/after to be
identical.

> [...]
>  	IW_HANDLER(SIOCSIWRTS,		(iw_handler)cfg80211_wext_siwrts),
^^^ I think these are fixed explicitly later, but maybe better to just
collapse them into this patch?

> [...]
> @@ -1391,15 +1406,15 @@ static const iw_handler	orinoco_handler[] = {
>    Added typecasting since we no longer use iwreq_data -- Moustafa
>   */
>  static const iw_handler	orinoco_private_handler[] = {
> -	[0] = (iw_handler)orinoco_ioctl_reset,
> -	[1] = (iw_handler)orinoco_ioctl_reset,
> -	[2] = (iw_handler)orinoco_ioctl_setport3,
> -	[3] = (iw_handler)orinoco_ioctl_getport3,
> -	[4] = (iw_handler)orinoco_ioctl_setpreamble,
> -	[5] = (iw_handler)orinoco_ioctl_getpreamble,
> -	[6] = (iw_handler)orinoco_ioctl_setibssport,
> -	[7] = (iw_handler)orinoco_ioctl_getibssport,
> -	[9] = (iw_handler)orinoco_ioctl_getrid,
> +	[0] = orinoco_ioctl_reset,
> +	[1] = orinoco_ioctl_reset,
> +	[2] = orinoco_ioctl_setport3,
> +	[3] = orinoco_ioctl_getport3,
> +	[4] = orinoco_ioctl_setpreamble,
> +	[5] = orinoco_ioctl_getpreamble,
> +	[6] = orinoco_ioctl_setibssport,
> +	[7] = orinoco_ioctl_getibssport,
> +	[9] = orinoco_ioctl_getrid,

Oops, I broke atmel. These really are 0-indexed...

 static const iw_handler atmel_private_handler[] =
 {
-	NULL,				/* SIOCIWFIRSTPRIV */
+	IW_HANDLER(SIOCIWFIRSTPRIV,	NULL),
 };
 
I'll send a fix!
diff mbox series

Patch

diff --git a/drivers/net/wireless/intersil/orinoco/wext.c b/drivers/net/wireless/intersil/orinoco/wext.c
index 4a01260027bc..b8eb5d60192f 100644
--- a/drivers/net/wireless/intersil/orinoco/wext.c
+++ b/drivers/net/wireless/intersil/orinoco/wext.c
@@ -154,9 +154,10 @@  static struct iw_statistics *orinoco_get_wireless_stats(struct net_device *dev)
 
 static int orinoco_ioctl_setwap(struct net_device *dev,
 				struct iw_request_info *info,
-				struct sockaddr *ap_addr,
+				union iwreq_data *wrqu,
 				char *extra)
 {
+	struct sockaddr *ap_addr = &wrqu->ap_addr;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int err = -EINPROGRESS;		/* Call commit handler */
 	unsigned long flags;
@@ -213,9 +214,10 @@  static int orinoco_ioctl_setwap(struct net_device *dev,
 
 static int orinoco_ioctl_getwap(struct net_device *dev,
 				struct iw_request_info *info,
-				struct sockaddr *ap_addr,
+				union iwreq_data *wrqu,
 				char *extra)
 {
+	struct sockaddr *ap_addr = &wrqu->ap_addr;
 	struct orinoco_private *priv = ndev_priv(dev);
 
 	int err = 0;
@@ -234,9 +236,10 @@  static int orinoco_ioctl_getwap(struct net_device *dev,
 
 static int orinoco_ioctl_setiwencode(struct net_device *dev,
 				     struct iw_request_info *info,
-				     struct iw_point *erq,
+				     union iwreq_data *wrqu,
 				     char *keybuf)
 {
+	struct iw_point *erq = &wrqu->encoding;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int index = (erq->flags & IW_ENCODE_INDEX) - 1;
 	int setindex = priv->tx_key;
@@ -325,9 +328,10 @@  static int orinoco_ioctl_setiwencode(struct net_device *dev,
 
 static int orinoco_ioctl_getiwencode(struct net_device *dev,
 				     struct iw_request_info *info,
-				     struct iw_point *erq,
+				     union iwreq_data *wrqu,
 				     char *keybuf)
 {
+	struct iw_point *erq = &wrqu->encoding;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int index = (erq->flags & IW_ENCODE_INDEX) - 1;
 	unsigned long flags;
@@ -361,9 +365,10 @@  static int orinoco_ioctl_getiwencode(struct net_device *dev,
 
 static int orinoco_ioctl_setessid(struct net_device *dev,
 				  struct iw_request_info *info,
-				  struct iw_point *erq,
+				  union iwreq_data *wrqu,
 				  char *essidbuf)
 {
+	struct iw_point *erq = &wrqu->essid;
 	struct orinoco_private *priv = ndev_priv(dev);
 	unsigned long flags;
 
@@ -392,9 +397,10 @@  static int orinoco_ioctl_setessid(struct net_device *dev,
 
 static int orinoco_ioctl_getessid(struct net_device *dev,
 				  struct iw_request_info *info,
-				  struct iw_point *erq,
+				  union iwreq_data *wrqu,
 				  char *essidbuf)
 {
+	struct iw_point *erq = &wrqu->essid;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int active;
 	int err = 0;
@@ -420,9 +426,10 @@  static int orinoco_ioctl_getessid(struct net_device *dev,
 
 static int orinoco_ioctl_setfreq(struct net_device *dev,
 				 struct iw_request_info *info,
-				 struct iw_freq *frq,
+				 union iwreq_data *wrqu,
 				 char *extra)
 {
+	struct iw_freq *frq = &wrqu->freq;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int chan = -1;
 	unsigned long flags;
@@ -469,9 +476,10 @@  static int orinoco_ioctl_setfreq(struct net_device *dev,
 
 static int orinoco_ioctl_getfreq(struct net_device *dev,
 				 struct iw_request_info *info,
-				 struct iw_freq *frq,
+				 union iwreq_data *wrqu,
 				 char *extra)
 {
+	struct iw_freq *frq = &wrqu->freq;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int tmp;
 
@@ -488,9 +496,10 @@  static int orinoco_ioctl_getfreq(struct net_device *dev,
 
 static int orinoco_ioctl_getsens(struct net_device *dev,
 				 struct iw_request_info *info,
-				 struct iw_param *srq,
+				 union iwreq_data *wrqu,
 				 char *extra)
 {
+	struct iw_param *srq = &wrqu->sens;
 	struct orinoco_private *priv = ndev_priv(dev);
 	struct hermes *hw = &priv->hw;
 	u16 val;
@@ -517,9 +526,10 @@  static int orinoco_ioctl_getsens(struct net_device *dev,
 
 static int orinoco_ioctl_setsens(struct net_device *dev,
 				 struct iw_request_info *info,
-				 struct iw_param *srq,
+				 union iwreq_data *wrqu,
 				 char *extra)
 {
+	struct iw_param *srq = &wrqu->sens;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int val = srq->value;
 	unsigned long flags;
@@ -540,9 +550,10 @@  static int orinoco_ioctl_setsens(struct net_device *dev,
 
 static int orinoco_ioctl_setrate(struct net_device *dev,
 				 struct iw_request_info *info,
-				 struct iw_param *rrq,
+				 union iwreq_data *wrqu,
 				 char *extra)
 {
+	struct iw_param *rrq = &wrqu->bitrate;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int ratemode;
 	int bitrate; /* 100s of kilobits */
@@ -574,9 +585,10 @@  static int orinoco_ioctl_setrate(struct net_device *dev,
 
 static int orinoco_ioctl_getrate(struct net_device *dev,
 				 struct iw_request_info *info,
-				 struct iw_param *rrq,
+				 union iwreq_data *wrqu,
 				 char *extra)
 {
+	struct iw_param *rrq = &wrqu->bitrate;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int err = 0;
 	int bitrate, automatic;
@@ -610,9 +622,10 @@  static int orinoco_ioctl_getrate(struct net_device *dev,
 
 static int orinoco_ioctl_setpower(struct net_device *dev,
 				  struct iw_request_info *info,
-				  struct iw_param *prq,
+				  union iwreq_data *wrqu,
 				  char *extra)
 {
+	struct iw_param *prq = &wrqu->power;
 	struct orinoco_private *priv = ndev_priv(dev);
 	int err = -EINPROGRESS;		/* Call commit handler */
 	unsigned long flags;
@@ -664,9 +677,10 @@  static int orinoco_ioctl_setpower(struct net_device *dev,
 
 static int orinoco_ioctl_getpower(struct net_device *dev,
 				  struct iw_request_info *info,
-				  struct iw_param *prq,
+				  union iwreq_data *wrqu,
 				  char *extra)
 {
+	struct iw_param *prq = &wrqu->power;
 	struct orinoco_private *priv = ndev_priv(dev);
 	struct hermes *hw = &priv->hw;
 	int err = 0;
@@ -1097,7 +1111,7 @@  static int orinoco_ioctl_set_mlme(struct net_device *dev,
 
 static int orinoco_ioctl_reset(struct net_device *dev,
 			       struct iw_request_info *info,
-			       void *wrqu,
+			       union iwreq_data *wrqu,
 			       char *extra)
 {
 	struct orinoco_private *priv = ndev_priv(dev);
@@ -1121,7 +1135,7 @@  static int orinoco_ioctl_reset(struct net_device *dev,
 
 static int orinoco_ioctl_setibssport(struct net_device *dev,
 				     struct iw_request_info *info,
-				     void *wrqu,
+				     union iwreq_data *wrqu,
 				     char *extra)
 
 {
@@ -1143,7 +1157,7 @@  static int orinoco_ioctl_setibssport(struct net_device *dev,
 
 static int orinoco_ioctl_getibssport(struct net_device *dev,
 				     struct iw_request_info *info,
-				     void *wrqu,
+				     union iwreq_data *wrqu,
 				     char *extra)
 {
 	struct orinoco_private *priv = ndev_priv(dev);
@@ -1155,7 +1169,7 @@  static int orinoco_ioctl_getibssport(struct net_device *dev,
 
 static int orinoco_ioctl_setport3(struct net_device *dev,
 				  struct iw_request_info *info,
-				  void *wrqu,
+				  union iwreq_data *wrqu,
 				  char *extra)
 {
 	struct orinoco_private *priv = ndev_priv(dev);
@@ -1201,7 +1215,7 @@  static int orinoco_ioctl_setport3(struct net_device *dev,
 
 static int orinoco_ioctl_getport3(struct net_device *dev,
 				  struct iw_request_info *info,
-				  void *wrqu,
+				  union iwreq_data *wrqu,
 				  char *extra)
 {
 	struct orinoco_private *priv = ndev_priv(dev);
@@ -1213,7 +1227,7 @@  static int orinoco_ioctl_getport3(struct net_device *dev,
 
 static int orinoco_ioctl_setpreamble(struct net_device *dev,
 				     struct iw_request_info *info,
-				     void *wrqu,
+				     union iwreq_data *wrqu,
 				     char *extra)
 {
 	struct orinoco_private *priv = ndev_priv(dev);
@@ -1245,7 +1259,7 @@  static int orinoco_ioctl_setpreamble(struct net_device *dev,
 
 static int orinoco_ioctl_getpreamble(struct net_device *dev,
 				     struct iw_request_info *info,
-				     void *wrqu,
+				     union iwreq_data *wrqu,
 				     char *extra)
 {
 	struct orinoco_private *priv = ndev_priv(dev);
@@ -1265,9 +1279,10 @@  static int orinoco_ioctl_getpreamble(struct net_device *dev,
  * For Wireless Tools 25 and 26 append "dummy" are the end. */
 static int orinoco_ioctl_getrid(struct net_device *dev,
 				struct iw_request_info *info,
-				struct iw_point *data,
+				union iwreq_data *wrqu,
 				char *extra)
 {
+	struct iw_point *data = &wrqu->data;
 	struct orinoco_private *priv = ndev_priv(dev);
 	struct hermes *hw = &priv->hw;
 	int rid = data->flags;
@@ -1303,7 +1318,7 @@  static int orinoco_ioctl_getrid(struct net_device *dev,
 /* Commit handler, called after set operations */
 static int orinoco_ioctl_commit(struct net_device *dev,
 				struct iw_request_info *info,
-				void *wrqu,
+				union iwreq_data *wrqu,
 				char *extra)
 {
 	struct orinoco_private *priv = ndev_priv(dev);
@@ -1347,36 +1362,36 @@  static const struct iw_priv_args orinoco_privtab[] = {
  */
 
 static const iw_handler	orinoco_handler[] = {
-	IW_HANDLER(SIOCSIWCOMMIT,	(iw_handler)orinoco_ioctl_commit),
+	IW_HANDLER(SIOCSIWCOMMIT,	orinoco_ioctl_commit),
 	IW_HANDLER(SIOCGIWNAME,		(iw_handler)cfg80211_wext_giwname),
-	IW_HANDLER(SIOCSIWFREQ,		(iw_handler)orinoco_ioctl_setfreq),
-	IW_HANDLER(SIOCGIWFREQ,		(iw_handler)orinoco_ioctl_getfreq),
+	IW_HANDLER(SIOCSIWFREQ,		orinoco_ioctl_setfreq),
+	IW_HANDLER(SIOCGIWFREQ,		orinoco_ioctl_getfreq),
 	IW_HANDLER(SIOCSIWMODE,		(iw_handler)cfg80211_wext_siwmode),
 	IW_HANDLER(SIOCGIWMODE,		(iw_handler)cfg80211_wext_giwmode),
-	IW_HANDLER(SIOCSIWSENS,		(iw_handler)orinoco_ioctl_setsens),
-	IW_HANDLER(SIOCGIWSENS,		(iw_handler)orinoco_ioctl_getsens),
+	IW_HANDLER(SIOCSIWSENS,		orinoco_ioctl_setsens),
+	IW_HANDLER(SIOCGIWSENS,		orinoco_ioctl_getsens),
 	IW_HANDLER(SIOCGIWRANGE,	(iw_handler)cfg80211_wext_giwrange),
 	IW_HANDLER(SIOCSIWSPY,		iw_handler_set_spy),
 	IW_HANDLER(SIOCGIWSPY,		iw_handler_get_spy),
 	IW_HANDLER(SIOCSIWTHRSPY,	iw_handler_set_thrspy),
 	IW_HANDLER(SIOCGIWTHRSPY,	iw_handler_get_thrspy),
-	IW_HANDLER(SIOCSIWAP,		(iw_handler)orinoco_ioctl_setwap),
-	IW_HANDLER(SIOCGIWAP,		(iw_handler)orinoco_ioctl_getwap),
+	IW_HANDLER(SIOCSIWAP,		orinoco_ioctl_setwap),
+	IW_HANDLER(SIOCGIWAP,		orinoco_ioctl_getwap),
 	IW_HANDLER(SIOCSIWSCAN,		(iw_handler)cfg80211_wext_siwscan),
 	IW_HANDLER(SIOCGIWSCAN,		(iw_handler)cfg80211_wext_giwscan),
-	IW_HANDLER(SIOCSIWESSID,	(iw_handler)orinoco_ioctl_setessid),
-	IW_HANDLER(SIOCGIWESSID,	(iw_handler)orinoco_ioctl_getessid),
-	IW_HANDLER(SIOCSIWRATE,		(iw_handler)orinoco_ioctl_setrate),
-	IW_HANDLER(SIOCGIWRATE,		(iw_handler)orinoco_ioctl_getrate),
+	IW_HANDLER(SIOCSIWESSID,	orinoco_ioctl_setessid),
+	IW_HANDLER(SIOCGIWESSID,	orinoco_ioctl_getessid),
+	IW_HANDLER(SIOCSIWRATE,		orinoco_ioctl_setrate),
+	IW_HANDLER(SIOCGIWRATE,		orinoco_ioctl_getrate),
 	IW_HANDLER(SIOCSIWRTS,		(iw_handler)cfg80211_wext_siwrts),
 	IW_HANDLER(SIOCGIWRTS,		(iw_handler)cfg80211_wext_giwrts),
 	IW_HANDLER(SIOCSIWFRAG,		(iw_handler)cfg80211_wext_siwfrag),
 	IW_HANDLER(SIOCGIWFRAG,		(iw_handler)cfg80211_wext_giwfrag),
 	IW_HANDLER(SIOCGIWRETRY,	(iw_handler)cfg80211_wext_giwretry),
-	IW_HANDLER(SIOCSIWENCODE,	(iw_handler)orinoco_ioctl_setiwencode),
-	IW_HANDLER(SIOCGIWENCODE,	(iw_handler)orinoco_ioctl_getiwencode),
-	IW_HANDLER(SIOCSIWPOWER,	(iw_handler)orinoco_ioctl_setpower),
-	IW_HANDLER(SIOCGIWPOWER,	(iw_handler)orinoco_ioctl_getpower),
+	IW_HANDLER(SIOCSIWENCODE,	orinoco_ioctl_setiwencode),
+	IW_HANDLER(SIOCGIWENCODE,	orinoco_ioctl_getiwencode),
+	IW_HANDLER(SIOCSIWPOWER,	orinoco_ioctl_setpower),
+	IW_HANDLER(SIOCGIWPOWER,	orinoco_ioctl_getpower),
 	IW_HANDLER(SIOCSIWGENIE,	orinoco_ioctl_set_genie),
 	IW_HANDLER(SIOCGIWGENIE,	orinoco_ioctl_get_genie),
 	IW_HANDLER(SIOCSIWMLME,		orinoco_ioctl_set_mlme),
@@ -1391,15 +1406,15 @@  static const iw_handler	orinoco_handler[] = {
   Added typecasting since we no longer use iwreq_data -- Moustafa
  */
 static const iw_handler	orinoco_private_handler[] = {
-	[0] = (iw_handler)orinoco_ioctl_reset,
-	[1] = (iw_handler)orinoco_ioctl_reset,
-	[2] = (iw_handler)orinoco_ioctl_setport3,
-	[3] = (iw_handler)orinoco_ioctl_getport3,
-	[4] = (iw_handler)orinoco_ioctl_setpreamble,
-	[5] = (iw_handler)orinoco_ioctl_getpreamble,
-	[6] = (iw_handler)orinoco_ioctl_setibssport,
-	[7] = (iw_handler)orinoco_ioctl_getibssport,
-	[9] = (iw_handler)orinoco_ioctl_getrid,
+	[0] = orinoco_ioctl_reset,
+	[1] = orinoco_ioctl_reset,
+	[2] = orinoco_ioctl_setport3,
+	[3] = orinoco_ioctl_getport3,
+	[4] = orinoco_ioctl_setpreamble,
+	[5] = orinoco_ioctl_getpreamble,
+	[6] = orinoco_ioctl_setibssport,
+	[7] = orinoco_ioctl_getibssport,
+	[9] = orinoco_ioctl_getrid,
 };
 
 const struct iw_handler_def orinoco_handler_def = {