From 02ae6a7034d7b2e3d89e33d73da10a1f156789a0 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Tue, 8 Nov 2022 14:23:55 -0600 Subject: wifi: cfg80211: Avoid clashing function prototypes 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 73 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, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ../drivers/net/wireless/intersil/orinoco/wext.c:1390:27: error: incompatible function pointer types initializing 'const iw_handler' (aka 'int (*const)(struct net_device *, struct iw_request_info *, union iwreq_data *, char *)') with an expression of type 'int (struct net_device *, struct iw_request_info *, struct iw_param *, char *)' [-Wincompatible-function-pointer-types] IW_HANDLER(SIOCGIWRETRY, cfg80211_wext_giwretry), ^~~~~~~~~~~~~~~~~~~~~~ The cfg80211 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. There are no resulting binary differences before/after changes. These changes were made partly manually and partly with the help of Coccinelle. Link: https://github.com/KSPP/linux/issues/234 Link: https://reviews.llvm.org/D134831 [1] Signed-off-by: Gustavo A. R. Silva Reviewed-by: Kees Cook Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/a68822bf8dd587988131bb6a295280cb4293f05d.1667934775.git.gustavoars@kernel.org --- net/wireless/scan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/wireless/scan.c') diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 806a5f1330ff..853619bc0f1a 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -3229,8 +3229,9 @@ static int ieee80211_scan_results(struct cfg80211_registered_device *rdev, int cfg80211_wext_giwscan(struct net_device *dev, struct iw_request_info *info, - struct iw_point *data, char *extra) + union iwreq_data *wrqu, char *extra) { + struct iw_point *data = &wrqu->data; struct cfg80211_registered_device *rdev; int res; -- cgit v1.2.3