* [PATCH net] cfg80211: fix callback type mismatches in wext-compat
@ 2020-11-17 20:59 Sami Tolvanen
2020-11-17 21:44 ` Kees Cook
2020-11-20 19:18 ` Kees Cook
0 siblings, 2 replies; 6+ messages in thread
From: Sami Tolvanen @ 2020-11-17 20:59 UTC (permalink / raw)
To: Johannes Berg, David S. Miller, Jakub Kicinski
Cc: Kees Cook, linux-wireless, netdev, linux-kernel, Sami Tolvanen,
Sedat Dilek
Instead of casting callback functions to type iw_handler, which trips
indirect call checking with Clang's Control-Flow Integrity (CFI), add
stub functions with the correct function type for the callbacks.
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
net/wireless/wext-compat.c | 103 +++++++++++++++++++++++++------------
1 file changed, 71 insertions(+), 32 deletions(-)
diff --git a/net/wireless/wext-compat.c b/net/wireless/wext-compat.c
index 78f2927ead7f..cf54c6e5b397 100644
--- a/net/wireless/wext-compat.c
+++ b/net/wireless/wext-compat.c
@@ -1472,39 +1472,78 @@ static int cfg80211_wext_siwpmksa(struct net_device *dev,
}
}
+#define DEFINE_WEXT_COMPAT_STUB(func, type) \
+ static int __ ## func(struct net_device *dev, \
+ struct iw_request_info *info, \
+ union iwreq_data *wrqu, \
+ char *extra) \
+ { \
+ return func(dev, info, (type *)wrqu, extra); \
+ }
+
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwname, char)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwfreq, struct iw_freq)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwfreq, struct iw_freq)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwmode, u32)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwmode, u32)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwrange, struct iw_point)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwap, struct sockaddr)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwap, struct sockaddr)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwmlme, struct iw_point)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwscan, struct iw_point)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwessid, struct iw_point)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwessid, struct iw_point)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwrate, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwrate, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwrts, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwrts, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwfrag, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwfrag, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwretry, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwretry, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwencode, struct iw_point)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwencode, struct iw_point)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwpower, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwpower, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwgenie, struct iw_point)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwauth, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwauth, struct iw_param)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwencodeext, struct iw_point)
+DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwpmksa, struct iw_point)
+
static const iw_handler cfg80211_handlers[] = {
- [IW_IOCTL_IDX(SIOCGIWNAME)] = (iw_handler) cfg80211_wext_giwname,
- [IW_IOCTL_IDX(SIOCSIWFREQ)] = (iw_handler) cfg80211_wext_siwfreq,
- [IW_IOCTL_IDX(SIOCGIWFREQ)] = (iw_handler) cfg80211_wext_giwfreq,
- [IW_IOCTL_IDX(SIOCSIWMODE)] = (iw_handler) cfg80211_wext_siwmode,
- [IW_IOCTL_IDX(SIOCGIWMODE)] = (iw_handler) cfg80211_wext_giwmode,
- [IW_IOCTL_IDX(SIOCGIWRANGE)] = (iw_handler) cfg80211_wext_giwrange,
- [IW_IOCTL_IDX(SIOCSIWAP)] = (iw_handler) cfg80211_wext_siwap,
- [IW_IOCTL_IDX(SIOCGIWAP)] = (iw_handler) cfg80211_wext_giwap,
- [IW_IOCTL_IDX(SIOCSIWMLME)] = (iw_handler) cfg80211_wext_siwmlme,
- [IW_IOCTL_IDX(SIOCSIWSCAN)] = (iw_handler) cfg80211_wext_siwscan,
- [IW_IOCTL_IDX(SIOCGIWSCAN)] = (iw_handler) cfg80211_wext_giwscan,
- [IW_IOCTL_IDX(SIOCSIWESSID)] = (iw_handler) cfg80211_wext_siwessid,
- [IW_IOCTL_IDX(SIOCGIWESSID)] = (iw_handler) cfg80211_wext_giwessid,
- [IW_IOCTL_IDX(SIOCSIWRATE)] = (iw_handler) cfg80211_wext_siwrate,
- [IW_IOCTL_IDX(SIOCGIWRATE)] = (iw_handler) cfg80211_wext_giwrate,
- [IW_IOCTL_IDX(SIOCSIWRTS)] = (iw_handler) cfg80211_wext_siwrts,
- [IW_IOCTL_IDX(SIOCGIWRTS)] = (iw_handler) cfg80211_wext_giwrts,
- [IW_IOCTL_IDX(SIOCSIWFRAG)] = (iw_handler) cfg80211_wext_siwfrag,
- [IW_IOCTL_IDX(SIOCGIWFRAG)] = (iw_handler) cfg80211_wext_giwfrag,
- [IW_IOCTL_IDX(SIOCSIWTXPOW)] = (iw_handler) cfg80211_wext_siwtxpower,
- [IW_IOCTL_IDX(SIOCGIWTXPOW)] = (iw_handler) cfg80211_wext_giwtxpower,
- [IW_IOCTL_IDX(SIOCSIWRETRY)] = (iw_handler) cfg80211_wext_siwretry,
- [IW_IOCTL_IDX(SIOCGIWRETRY)] = (iw_handler) cfg80211_wext_giwretry,
- [IW_IOCTL_IDX(SIOCSIWENCODE)] = (iw_handler) cfg80211_wext_siwencode,
- [IW_IOCTL_IDX(SIOCGIWENCODE)] = (iw_handler) cfg80211_wext_giwencode,
- [IW_IOCTL_IDX(SIOCSIWPOWER)] = (iw_handler) cfg80211_wext_siwpower,
- [IW_IOCTL_IDX(SIOCGIWPOWER)] = (iw_handler) cfg80211_wext_giwpower,
- [IW_IOCTL_IDX(SIOCSIWGENIE)] = (iw_handler) cfg80211_wext_siwgenie,
- [IW_IOCTL_IDX(SIOCSIWAUTH)] = (iw_handler) cfg80211_wext_siwauth,
- [IW_IOCTL_IDX(SIOCGIWAUTH)] = (iw_handler) cfg80211_wext_giwauth,
- [IW_IOCTL_IDX(SIOCSIWENCODEEXT)]= (iw_handler) cfg80211_wext_siwencodeext,
- [IW_IOCTL_IDX(SIOCSIWPMKSA)] = (iw_handler) cfg80211_wext_siwpmksa,
+ [IW_IOCTL_IDX(SIOCGIWNAME)] = __cfg80211_wext_giwname,
+ [IW_IOCTL_IDX(SIOCSIWFREQ)] = __cfg80211_wext_siwfreq,
+ [IW_IOCTL_IDX(SIOCGIWFREQ)] = __cfg80211_wext_giwfreq,
+ [IW_IOCTL_IDX(SIOCSIWMODE)] = __cfg80211_wext_siwmode,
+ [IW_IOCTL_IDX(SIOCGIWMODE)] = __cfg80211_wext_giwmode,
+ [IW_IOCTL_IDX(SIOCGIWRANGE)] = __cfg80211_wext_giwrange,
+ [IW_IOCTL_IDX(SIOCSIWAP)] = __cfg80211_wext_siwap,
+ [IW_IOCTL_IDX(SIOCGIWAP)] = __cfg80211_wext_giwap,
+ [IW_IOCTL_IDX(SIOCSIWMLME)] = __cfg80211_wext_siwmlme,
+ [IW_IOCTL_IDX(SIOCSIWSCAN)] = cfg80211_wext_siwscan,
+ [IW_IOCTL_IDX(SIOCGIWSCAN)] = __cfg80211_wext_giwscan,
+ [IW_IOCTL_IDX(SIOCSIWESSID)] = __cfg80211_wext_siwessid,
+ [IW_IOCTL_IDX(SIOCGIWESSID)] = __cfg80211_wext_giwessid,
+ [IW_IOCTL_IDX(SIOCSIWRATE)] = __cfg80211_wext_siwrate,
+ [IW_IOCTL_IDX(SIOCGIWRATE)] = __cfg80211_wext_giwrate,
+ [IW_IOCTL_IDX(SIOCSIWRTS)] = __cfg80211_wext_siwrts,
+ [IW_IOCTL_IDX(SIOCGIWRTS)] = __cfg80211_wext_giwrts,
+ [IW_IOCTL_IDX(SIOCSIWFRAG)] = __cfg80211_wext_siwfrag,
+ [IW_IOCTL_IDX(SIOCGIWFRAG)] = __cfg80211_wext_giwfrag,
+ [IW_IOCTL_IDX(SIOCSIWTXPOW)] = cfg80211_wext_siwtxpower,
+ [IW_IOCTL_IDX(SIOCGIWTXPOW)] = cfg80211_wext_giwtxpower,
+ [IW_IOCTL_IDX(SIOCSIWRETRY)] = __cfg80211_wext_siwretry,
+ [IW_IOCTL_IDX(SIOCGIWRETRY)] = __cfg80211_wext_giwretry,
+ [IW_IOCTL_IDX(SIOCSIWENCODE)] = __cfg80211_wext_siwencode,
+ [IW_IOCTL_IDX(SIOCGIWENCODE)] = __cfg80211_wext_giwencode,
+ [IW_IOCTL_IDX(SIOCSIWPOWER)] = __cfg80211_wext_siwpower,
+ [IW_IOCTL_IDX(SIOCGIWPOWER)] = __cfg80211_wext_giwpower,
+ [IW_IOCTL_IDX(SIOCSIWGENIE)] = __cfg80211_wext_siwgenie,
+ [IW_IOCTL_IDX(SIOCSIWAUTH)] = __cfg80211_wext_siwauth,
+ [IW_IOCTL_IDX(SIOCGIWAUTH)] = __cfg80211_wext_giwauth,
+ [IW_IOCTL_IDX(SIOCSIWENCODEEXT)]= __cfg80211_wext_siwencodeext,
+ [IW_IOCTL_IDX(SIOCSIWPMKSA)] = __cfg80211_wext_siwpmksa,
};
const struct iw_handler_def cfg80211_wext_handler = {
base-commit: 9c87c9f41245baa3fc4716cf39141439cf405b01
--
2.29.2.299.gdc1121823c-goog
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH net] cfg80211: fix callback type mismatches in wext-compat
2020-11-17 20:59 [PATCH net] cfg80211: fix callback type mismatches in wext-compat Sami Tolvanen
@ 2020-11-17 21:44 ` Kees Cook
2020-11-17 22:07 ` Sami Tolvanen
2020-11-20 19:18 ` Kees Cook
1 sibling, 1 reply; 6+ messages in thread
From: Kees Cook @ 2020-11-17 21:44 UTC (permalink / raw)
To: Sami Tolvanen
Cc: Johannes Berg, David S. Miller, Jakub Kicinski, linux-wireless,
netdev, linux-kernel, Sedat Dilek
On Tue, Nov 17, 2020 at 12:59:02PM -0800, Sami Tolvanen wrote:
> Instead of casting callback functions to type iw_handler, which trips
> indirect call checking with Clang's Control-Flow Integrity (CFI), add
> stub functions with the correct function type for the callbacks.
Oh, wow. iw_handler with union iwreq_data look like really nasty hacks.
Aren't those just totally bypassing type checking? Where do the
callbacks actually happen? I couldn't find them...
>
> Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
> ---
> net/wireless/wext-compat.c | 103 +++++++++++++++++++++++++------------
> 1 file changed, 71 insertions(+), 32 deletions(-)
>
> diff --git a/net/wireless/wext-compat.c b/net/wireless/wext-compat.c
> index 78f2927ead7f..cf54c6e5b397 100644
> --- a/net/wireless/wext-compat.c
> +++ b/net/wireless/wext-compat.c
> @@ -1472,39 +1472,78 @@ static int cfg80211_wext_siwpmksa(struct net_device *dev,
> }
> }
>
> +#define DEFINE_WEXT_COMPAT_STUB(func, type) \
> + static int __ ## func(struct net_device *dev, \
> + struct iw_request_info *info, \
> + union iwreq_data *wrqu, \
> + char *extra) \
> + { \
> + return func(dev, info, (type *)wrqu, extra); \
> + }
> +
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwname, char)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwfreq, struct iw_freq)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwfreq, struct iw_freq)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwmode, u32)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwmode, u32)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwrange, struct iw_point)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwap, struct sockaddr)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwap, struct sockaddr)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwmlme, struct iw_point)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwscan, struct iw_point)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwessid, struct iw_point)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwessid, struct iw_point)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwrate, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwrate, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwrts, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwrts, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwfrag, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwfrag, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwretry, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwretry, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwencode, struct iw_point)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwencode, struct iw_point)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwpower, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwpower, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwgenie, struct iw_point)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_giwauth, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwauth, struct iw_param)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwencodeext, struct iw_point)
> +DEFINE_WEXT_COMPAT_STUB(cfg80211_wext_siwpmksa, struct iw_point)
> +
> static const iw_handler cfg80211_handlers[] = {
> - [IW_IOCTL_IDX(SIOCGIWNAME)] = (iw_handler) cfg80211_wext_giwname,
> - [IW_IOCTL_IDX(SIOCSIWFREQ)] = (iw_handler) cfg80211_wext_siwfreq,
> - [IW_IOCTL_IDX(SIOCGIWFREQ)] = (iw_handler) cfg80211_wext_giwfreq,
> - [IW_IOCTL_IDX(SIOCSIWMODE)] = (iw_handler) cfg80211_wext_siwmode,
> - [IW_IOCTL_IDX(SIOCGIWMODE)] = (iw_handler) cfg80211_wext_giwmode,
> - [IW_IOCTL_IDX(SIOCGIWRANGE)] = (iw_handler) cfg80211_wext_giwrange,
> - [IW_IOCTL_IDX(SIOCSIWAP)] = (iw_handler) cfg80211_wext_siwap,
> - [IW_IOCTL_IDX(SIOCGIWAP)] = (iw_handler) cfg80211_wext_giwap,
> - [IW_IOCTL_IDX(SIOCSIWMLME)] = (iw_handler) cfg80211_wext_siwmlme,
> - [IW_IOCTL_IDX(SIOCSIWSCAN)] = (iw_handler) cfg80211_wext_siwscan,
> - [IW_IOCTL_IDX(SIOCGIWSCAN)] = (iw_handler) cfg80211_wext_giwscan,
> - [IW_IOCTL_IDX(SIOCSIWESSID)] = (iw_handler) cfg80211_wext_siwessid,
> - [IW_IOCTL_IDX(SIOCGIWESSID)] = (iw_handler) cfg80211_wext_giwessid,
> - [IW_IOCTL_IDX(SIOCSIWRATE)] = (iw_handler) cfg80211_wext_siwrate,
> - [IW_IOCTL_IDX(SIOCGIWRATE)] = (iw_handler) cfg80211_wext_giwrate,
> - [IW_IOCTL_IDX(SIOCSIWRTS)] = (iw_handler) cfg80211_wext_siwrts,
> - [IW_IOCTL_IDX(SIOCGIWRTS)] = (iw_handler) cfg80211_wext_giwrts,
> - [IW_IOCTL_IDX(SIOCSIWFRAG)] = (iw_handler) cfg80211_wext_siwfrag,
> - [IW_IOCTL_IDX(SIOCGIWFRAG)] = (iw_handler) cfg80211_wext_giwfrag,
> - [IW_IOCTL_IDX(SIOCSIWTXPOW)] = (iw_handler) cfg80211_wext_siwtxpower,
> - [IW_IOCTL_IDX(SIOCGIWTXPOW)] = (iw_handler) cfg80211_wext_giwtxpower,
> - [IW_IOCTL_IDX(SIOCSIWRETRY)] = (iw_handler) cfg80211_wext_siwretry,
> - [IW_IOCTL_IDX(SIOCGIWRETRY)] = (iw_handler) cfg80211_wext_giwretry,
> - [IW_IOCTL_IDX(SIOCSIWENCODE)] = (iw_handler) cfg80211_wext_siwencode,
> - [IW_IOCTL_IDX(SIOCGIWENCODE)] = (iw_handler) cfg80211_wext_giwencode,
> - [IW_IOCTL_IDX(SIOCSIWPOWER)] = (iw_handler) cfg80211_wext_siwpower,
> - [IW_IOCTL_IDX(SIOCGIWPOWER)] = (iw_handler) cfg80211_wext_giwpower,
> - [IW_IOCTL_IDX(SIOCSIWGENIE)] = (iw_handler) cfg80211_wext_siwgenie,
> - [IW_IOCTL_IDX(SIOCSIWAUTH)] = (iw_handler) cfg80211_wext_siwauth,
> - [IW_IOCTL_IDX(SIOCGIWAUTH)] = (iw_handler) cfg80211_wext_giwauth,
> - [IW_IOCTL_IDX(SIOCSIWENCODEEXT)]= (iw_handler) cfg80211_wext_siwencodeext,
> - [IW_IOCTL_IDX(SIOCSIWPMKSA)] = (iw_handler) cfg80211_wext_siwpmksa,
> + [IW_IOCTL_IDX(SIOCGIWNAME)] = __cfg80211_wext_giwname,
> + [IW_IOCTL_IDX(SIOCSIWFREQ)] = __cfg80211_wext_siwfreq,
> + [IW_IOCTL_IDX(SIOCGIWFREQ)] = __cfg80211_wext_giwfreq,
> + [IW_IOCTL_IDX(SIOCSIWMODE)] = __cfg80211_wext_siwmode,
> + [IW_IOCTL_IDX(SIOCGIWMODE)] = __cfg80211_wext_giwmode,
> + [IW_IOCTL_IDX(SIOCGIWRANGE)] = __cfg80211_wext_giwrange,
> + [IW_IOCTL_IDX(SIOCSIWAP)] = __cfg80211_wext_siwap,
> + [IW_IOCTL_IDX(SIOCGIWAP)] = __cfg80211_wext_giwap,
> + [IW_IOCTL_IDX(SIOCSIWMLME)] = __cfg80211_wext_siwmlme,
> + [IW_IOCTL_IDX(SIOCSIWSCAN)] = cfg80211_wext_siwscan,
> + [IW_IOCTL_IDX(SIOCGIWSCAN)] = __cfg80211_wext_giwscan,
> + [IW_IOCTL_IDX(SIOCSIWESSID)] = __cfg80211_wext_siwessid,
> + [IW_IOCTL_IDX(SIOCGIWESSID)] = __cfg80211_wext_giwessid,
> + [IW_IOCTL_IDX(SIOCSIWRATE)] = __cfg80211_wext_siwrate,
> + [IW_IOCTL_IDX(SIOCGIWRATE)] = __cfg80211_wext_giwrate,
> + [IW_IOCTL_IDX(SIOCSIWRTS)] = __cfg80211_wext_siwrts,
> + [IW_IOCTL_IDX(SIOCGIWRTS)] = __cfg80211_wext_giwrts,
> + [IW_IOCTL_IDX(SIOCSIWFRAG)] = __cfg80211_wext_siwfrag,
> + [IW_IOCTL_IDX(SIOCGIWFRAG)] = __cfg80211_wext_giwfrag,
> + [IW_IOCTL_IDX(SIOCSIWTXPOW)] = cfg80211_wext_siwtxpower,
> + [IW_IOCTL_IDX(SIOCGIWTXPOW)] = cfg80211_wext_giwtxpower,
> + [IW_IOCTL_IDX(SIOCSIWRETRY)] = __cfg80211_wext_siwretry,
> + [IW_IOCTL_IDX(SIOCGIWRETRY)] = __cfg80211_wext_giwretry,
> + [IW_IOCTL_IDX(SIOCSIWENCODE)] = __cfg80211_wext_siwencode,
> + [IW_IOCTL_IDX(SIOCGIWENCODE)] = __cfg80211_wext_giwencode,
> + [IW_IOCTL_IDX(SIOCSIWPOWER)] = __cfg80211_wext_siwpower,
> + [IW_IOCTL_IDX(SIOCGIWPOWER)] = __cfg80211_wext_giwpower,
> + [IW_IOCTL_IDX(SIOCSIWGENIE)] = __cfg80211_wext_siwgenie,
> + [IW_IOCTL_IDX(SIOCSIWAUTH)] = __cfg80211_wext_siwauth,
> + [IW_IOCTL_IDX(SIOCGIWAUTH)] = __cfg80211_wext_giwauth,
> + [IW_IOCTL_IDX(SIOCSIWENCODEEXT)]= __cfg80211_wext_siwencodeext,
> + [IW_IOCTL_IDX(SIOCSIWPMKSA)] = __cfg80211_wext_siwpmksa,
> };
>
> const struct iw_handler_def cfg80211_wext_handler = {
>
> base-commit: 9c87c9f41245baa3fc4716cf39141439cf405b01
> --
> 2.29.2.299.gdc1121823c-goog
>
--
Kees Cook
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH net] cfg80211: fix callback type mismatches in wext-compat
2020-11-17 21:44 ` Kees Cook
@ 2020-11-17 22:07 ` Sami Tolvanen
2020-11-20 19:26 ` Kees Cook
0 siblings, 1 reply; 6+ messages in thread
From: Sami Tolvanen @ 2020-11-17 22:07 UTC (permalink / raw)
To: Kees Cook
Cc: Johannes Berg, David S. Miller, Jakub Kicinski, linux-wireless,
netdev, LKML, Sedat Dilek
On Tue, Nov 17, 2020 at 1:45 PM Kees Cook <keescook@chromium.org> wrote:
>
> On Tue, Nov 17, 2020 at 12:59:02PM -0800, Sami Tolvanen wrote:
> > Instead of casting callback functions to type iw_handler, which trips
> > indirect call checking with Clang's Control-Flow Integrity (CFI), add
> > stub functions with the correct function type for the callbacks.
>
> Oh, wow. iw_handler with union iwreq_data look like really nasty hacks.
> Aren't those just totally bypassing type checking? Where do the
> callbacks actually happen? I couldn't find them...
The callbacks to these happen in ioctl_standard_call in wext-core.c.
Sami
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH net] cfg80211: fix callback type mismatches in wext-compat
2020-11-17 22:07 ` Sami Tolvanen
@ 2020-11-20 19:26 ` Kees Cook
2020-11-20 21:33 ` Johannes Berg
0 siblings, 1 reply; 6+ messages in thread
From: Kees Cook @ 2020-11-20 19:26 UTC (permalink / raw)
To: Sami Tolvanen
Cc: Johannes Berg, David S. Miller, Jakub Kicinski, linux-wireless,
netdev, LKML, Sedat Dilek
On Tue, Nov 17, 2020 at 02:07:43PM -0800, Sami Tolvanen wrote:
> On Tue, Nov 17, 2020 at 1:45 PM Kees Cook <keescook@chromium.org> wrote:
> >
> > On Tue, Nov 17, 2020 at 12:59:02PM -0800, Sami Tolvanen wrote:
> > > Instead of casting callback functions to type iw_handler, which trips
> > > indirect call checking with Clang's Control-Flow Integrity (CFI), add
> > > stub functions with the correct function type for the callbacks.
> >
> > Oh, wow. iw_handler with union iwreq_data look like really nasty hacks.
> > Aren't those just totally bypassing type checking? Where do the
> > callbacks actually happen? I couldn't find them...
>
> The callbacks to these happen in ioctl_standard_call in wext-core.c.
Thanks! If this is all the 'old compat' code, this patch looks fine. I
think new stuff should probably encode types in some fashion (rather
than via wrappers).
--
Kees Cook
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH net] cfg80211: fix callback type mismatches in wext-compat
2020-11-20 19:26 ` Kees Cook
@ 2020-11-20 21:33 ` Johannes Berg
0 siblings, 0 replies; 6+ messages in thread
From: Johannes Berg @ 2020-11-20 21:33 UTC (permalink / raw)
To: Kees Cook, Sami Tolvanen
Cc: David S. Miller, Jakub Kicinski, linux-wireless, netdev, LKML,
Sedat Dilek
On Fri, 2020-11-20 at 11:26 -0800, Kees Cook wrote:
> On Tue, Nov 17, 2020 at 02:07:43PM -0800, Sami Tolvanen wrote:
> > On Tue, Nov 17, 2020 at 1:45 PM Kees Cook <keescook@chromium.org> wrote:
> > > On Tue, Nov 17, 2020 at 12:59:02PM -0800, Sami Tolvanen wrote:
> > > > Instead of casting callback functions to type iw_handler, which trips
> > > > indirect call checking with Clang's Control-Flow Integrity (CFI), add
> > > > stub functions with the correct function type for the callbacks.
> > >
> > > Oh, wow. iw_handler with union iwreq_data look like really nasty hacks.
> > > Aren't those just totally bypassing type checking? Where do the
> > > callbacks actually happen? I couldn't find them...
> >
> > The callbacks to these happen in ioctl_standard_call in wext-core.c.
>
> Thanks! If this is all the 'old compat' code, this patch looks fine. I
> think new stuff should probably encode types in some fashion (rather
> than via wrappers).
Everything mentioning wext has been deprecated for something like 15
years ... so yeah. But people still use it :(
johannes
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH net] cfg80211: fix callback type mismatches in wext-compat
2020-11-17 20:59 [PATCH net] cfg80211: fix callback type mismatches in wext-compat Sami Tolvanen
2020-11-17 21:44 ` Kees Cook
@ 2020-11-20 19:18 ` Kees Cook
1 sibling, 0 replies; 6+ messages in thread
From: Kees Cook @ 2020-11-20 19:18 UTC (permalink / raw)
To: Sami Tolvanen
Cc: Johannes Berg, David S. Miller, Jakub Kicinski, linux-wireless,
netdev, linux-kernel, Sedat Dilek
On Tue, Nov 17, 2020 at 12:59:02PM -0800, Sami Tolvanen wrote:
> Instead of casting callback functions to type iw_handler, which trips
> indirect call checking with Clang's Control-Flow Integrity (CFI), add
> stub functions with the correct function type for the callbacks.
>
> Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
--
Kees Cook
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-11-20 21:34 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-11-17 20:59 [PATCH net] cfg80211: fix callback type mismatches in wext-compat Sami Tolvanen
2020-11-17 21:44 ` Kees Cook
2020-11-17 22:07 ` Sami Tolvanen
2020-11-20 19:26 ` Kees Cook
2020-11-20 21:33 ` Johannes Berg
2020-11-20 19:18 ` Kees Cook
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