[PATCH 0/6] staging: rtl8188eu and rtl8723bs - some fixes and cleanups

[PATCH 0/6] staging: rtl8188eu and rtl8723bs - some fixes and cleanups

[Larry Finger]

It was recently reported that staging drivers rtl8188eu and rtl8723bs
contained a security flaw because a parameter had not been checked.
The following patches fix that flaw and cleans up the routines.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>


Larry Finger (6):
  staging: rtl8188eu: Fix potential security hole
  staging: rtl8723bs: Fix potential security hole
  staging: rtl8188eu: Fix potential overuse of kernel memory
  staging: rtl8723bs: Fix potential overuse of kernel memory
  staging: rtl8188eu: Remove some unneeded goto statements
  staging: rtl8723bs: Remove unneeded goto statements

 .../staging/rtl8188eu/os_dep/ioctl_linux.c    | 40 +++++-----------
 .../staging/rtl8723bs/os_dep/ioctl_linux.c    | 47 +++++--------------
 2 files changed, 24 insertions(+), 63 deletions(-)

-- 
2.25.0

[PATCH 1/6] staging: rtl8188eu: Fix potential security hole

[Larry Finger]

In routine rtw_hostapd_ioctl(), the user-controlled p->length is assumed
to be at least the size of struct ieee_param size, but this assumption is
never checked. This could result in out-of-bounds read/write on kernel
heap in case a p->length less than the size of struct ieee_param is
specified by the user. If p->length is allowed to be greater than the size
of the struct, then a malicious user could be wasting kernel memory.
Fixes commit a2c60d42d97c ("Add files for new driver - part 16").

Reported by: Pietro Oliva <pietroliva@gmail.com>
Cc: Pietro Oliva <pietroliva@gmail.com>
Cc: Stable <stable@vger.kernel.org>
Fixes: a2c60d42d97c ("Add files for new driver - part 16").
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
---
 drivers/staging/rtl8188eu/os_dep/ioctl_linux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c b/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c
index 9b6ea86d1dcf..7d21f5799640 100644
--- a/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c
+++ b/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c
@@ -2796,7 +2796,7 @@ static int rtw_hostapd_ioctl(struct net_device *dev, struct iw_point *p)
 		goto out;
 	}
 
-	if (!p->pointer) {
+	if (!p->pointer || p->length != sizeof(struct ieee_param)) {
 		ret = -EINVAL;
 		goto out;
 	}
-- 
2.25.0

[PATCH 2/6] staging: rtl8723bs: Fix potential security hole

[Larry Finger]

In routine rtw_hostapd_ioctl(), the user-controlled p->length is assumed
to be at least the size of struct ieee_param size, but this assumption is
never checked. This could result in out-of-bounds read/write on kernel
heap in case a p->length less than the size of struct ieee_param is
specified by the user. If p->length is allowed to be greater than the size
of the struct, then a malicious user could be wasting kernel memory.
Fixes commit 554c0a3abf216 ("0taging: Add rtl8723bs sdio wifi driver").

Reported by: Pietro Oliva <pietroliva@gmail.com>
Cc: Pietro Oliva <pietroliva@gmail.com>
Cc: Stable <stable@vger.kernel.org>
Fixes 554c0a3abf216 ("0taging: Add rtl8723bs sdio wifi driver").
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
---
 drivers/staging/rtl8723bs/os_dep/ioctl_linux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
index db6528a01229..3128766dd50e 100644
--- a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
+++ b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
@@ -4207,7 +4207,7 @@ static int rtw_hostapd_ioctl(struct net_device *dev, struct iw_point *p)
 
 
 	/* if (p->length < sizeof(struct ieee_param) || !p->pointer) { */
-	if (!p->pointer) {
+	if (!p->pointer || p->length != sizeof(*param)) {
 		ret = -EINVAL;
 		goto out;
 	}
-- 
2.25.0

[PATCH 3/6] staging: rtl8188eu: Fix potential overuse of kernel memory

[Larry Finger]

In routine wpa_supplicant_ioctl(), the user-controlled p->length is
checked to be at least the size of struct ieee_param size, but the code
does not detect the case where p->length is greater than the size
of the struct, thus a malicious user could be wasting kernel memory.
Fixes commit a2c60d42d97c ("Add files for new driver - part 16").

Reported by: Pietro Oliva <pietroliva@gmail.com>
Cc: Pietro Oliva <pietroliva@gmail.com>
Cc: Stable <stable@vger.kernel.org>
Fixes commit a2c60d42d97c ("Add files for new driver - part 16").
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
---
 drivers/staging/rtl8188eu/os_dep/ioctl_linux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c b/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c
index 7d21f5799640..acca3ae8b254 100644
--- a/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c
+++ b/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c
@@ -2009,7 +2009,7 @@ static int wpa_supplicant_ioctl(struct net_device *dev, struct iw_point *p)
 	struct ieee_param *param;
 	uint ret = 0;
 
-	if (p->length < sizeof(struct ieee_param) || !p->pointer) {
+	if (!p->pointer || p->length != sizeof(struct ieee_param)) {
 		ret = -EINVAL;
 		goto out;
 	}
-- 
2.25.0

[PATCH 4/6] staging: rtl8723bs: Fix potential overuse of kernel memory

[Larry Finger]

In routine wpa_supplicant_ioctl(), the user-controlled p->length is
checked to be at least the size of struct ieee_param size, but the code
does not detect the case where p->length is greater than the size
of the struct, thus a malicious user could be wasting kernel memory.
Fixes commit 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver").

Reported by: Pietro Oliva <pietroliva@gmail.com>
Cc: Pietro Oliva <pietroliva@gmail.com>
Cc: Stable <stable@vger.kernel.org>
Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver").
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
-# Please enter the commit message for your changes. Lines starting
---
 drivers/staging/rtl8723bs/os_dep/ioctl_linux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
index 3128766dd50e..2ac0d84f090e 100644
--- a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
+++ b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
@@ -3373,7 +3373,7 @@ static int wpa_supplicant_ioctl(struct net_device *dev, struct iw_point *p)
 
 	/* down(&ieee->wx_sem); */
 
-	if (p->length < sizeof(struct ieee_param) || !p->pointer) {
+	if (!p->pointer || p->length != sizeof(struct ieee_param)) {
 		ret = -EINVAL;
 		goto out;
 	}
-- 
2.25.0

[PATCH 5/6] staging: rtl8188eu: Remove some unneeded goto statements

[Larry Finger]

In routines rtw_hostapd_ioctl() and wpa_supplicant_ioctl(), several
error conditions involve setting a variable indicating the error,
followed by a goto. The code following the target of that goto merely
returns the value. It is simpler, therefore to return the error value
immediately, and eliminate the got  target.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Pietro Oliva <pietroliva@gmail.com>
---
 .../staging/rtl8188eu/os_dep/ioctl_linux.c    | 40 ++++++-------------
 1 file changed, 12 insertions(+), 28 deletions(-)

diff --git a/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c b/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c
index acca3ae8b254..ba53959e1303 100644
--- a/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c
+++ b/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c
@@ -2009,21 +2009,16 @@ static int wpa_supplicant_ioctl(struct net_device *dev, struct iw_point *p)
 	struct ieee_param *param;
 	uint ret = 0;
 
-	if (!p->pointer || p->length != sizeof(struct ieee_param)) {
-		ret = -EINVAL;
-		goto out;
-	}
+	if (!p->pointer || p->length != sizeof(struct ieee_param))
+		return -EINVAL;
 
 	param = (struct ieee_param *)rtw_malloc(p->length);
-	if (!param) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	if (!param)
+		return -ENOMEM;
 
 	if (copy_from_user(param, p->pointer, p->length)) {
 		kfree(param);
-		ret = -EFAULT;
-		goto out;
+		return -EFAULT;
 	}
 
 	switch (param->cmd) {
@@ -2054,9 +2049,6 @@ static int wpa_supplicant_ioctl(struct net_device *dev, struct iw_point *p)
 		ret = -EFAULT;
 
 	kfree(param);
-
-out:
-
 	return ret;
 }
 
@@ -2791,26 +2783,19 @@ static int rtw_hostapd_ioctl(struct net_device *dev, struct iw_point *p)
 	* so, we just check hw_init_completed
 	*/
 
-	if (!padapter->hw_init_completed) {
-		ret = -EPERM;
-		goto out;
-	}
+	if (!padapter->hw_init_completed)
+		return -EPERM;
 
-	if (!p->pointer || p->length != sizeof(struct ieee_param)) {
-		ret = -EINVAL;
-		goto out;
-	}
+	if (!p->pointer || p->length != sizeof(struct ieee_param))
+		return -EINVAL;
 
 	param = (struct ieee_param *)rtw_malloc(p->length);
-	if (!param) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	if (!param)
+		return -ENOMEM;
 
 	if (copy_from_user(param, p->pointer, p->length)) {
 		kfree(param);
-		ret = -EFAULT;
-		goto out;
+		return -EFAULT;
 	}
 
 	switch (param->cmd) {
@@ -2865,7 +2850,6 @@ static int rtw_hostapd_ioctl(struct net_device *dev, struct iw_point *p)
 	if (ret == 0 && copy_to_user(p->pointer, param, p->length))
 		ret = -EFAULT;
 	kfree(param);
-out:
 	return ret;
 }
 #endif
-- 
2.25.0

[PATCH 6/6] staging: rtl8723bs: Remove unneeded goto statements

[Larry Finger]

In routines rtw_hostapd_ioctl() and wpa_supplicant_ioctl(), several
error conditions involve setting a variable indicating the error,
followed by a goto. The code following the target of that goto merely
returns the value. It is simpler, therefore to return the error value
immediately, and eliminate the got  target.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Pietro Oliva <pietroliva@gmail.com>
---
 .../staging/rtl8723bs/os_dep/ioctl_linux.c    | 47 +++++--------------
 1 file changed, 12 insertions(+), 35 deletions(-)

diff --git a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
index 2ac0d84f090e..9b9038e7deb1 100644
--- a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
+++ b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
@@ -3373,21 +3373,16 @@ static int wpa_supplicant_ioctl(struct net_device *dev, struct iw_point *p)
 
 	/* down(&ieee->wx_sem); */
 
-	if (!p->pointer || p->length != sizeof(struct ieee_param)) {
-		ret = -EINVAL;
-		goto out;
-	}
+	if (!p->pointer || p->length != sizeof(struct ieee_param))
+		return -EINVAL;
 
 	param = rtw_malloc(p->length);
-	if (param == NULL) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	if (param == NULL)
+		return -ENOMEM;
 
 	if (copy_from_user(param, p->pointer, p->length)) {
 		kfree(param);
-		ret = -EFAULT;
-		goto out;
+		return -EFAULT;
 	}
 
 	switch (param->cmd) {
@@ -3421,12 +3416,8 @@ static int wpa_supplicant_ioctl(struct net_device *dev, struct iw_point *p)
 
 	kfree(param);
 
-out:
-
 	/* up(&ieee->wx_sem); */
-
 	return ret;
-
 }
 
 static int rtw_set_encryption(struct net_device *dev, struct ieee_param *param, u32 param_len)
@@ -4200,28 +4191,19 @@ static int rtw_hostapd_ioctl(struct net_device *dev, struct iw_point *p)
 	* so, we just check hw_init_completed
 	*/
 
-	if (!padapter->hw_init_completed) {
-		ret = -EPERM;
-		goto out;
-	}
-
+	if (!padapter->hw_init_completed)
+		return -EPERM;
 
-	/* if (p->length < sizeof(struct ieee_param) || !p->pointer) { */
-	if (!p->pointer || p->length != sizeof(*param)) {
-		ret = -EINVAL;
-		goto out;
-	}
+	if (!p->pointer || p->length != sizeof(*param))
+		return -EINVAL;
 
 	param = rtw_malloc(p->length);
-	if (param == NULL) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	if (param == NULL)
+		return -ENOMEM;
 
 	if (copy_from_user(param, p->pointer, p->length)) {
 		kfree(param);
-		ret = -EFAULT;
-		goto out;
+		return -EFAULT;
 	}
 
 	/* DBG_871X("%s, cmd =%d\n", __func__, param->cmd); */
@@ -4321,13 +4303,8 @@ static int rtw_hostapd_ioctl(struct net_device *dev, struct iw_point *p)
 	if (ret == 0 && copy_to_user(p->pointer, param, p->length))
 		ret = -EFAULT;
 
-
 	kfree(param);
-
-out:
-
 	return ret;
-
 }
 
 static int rtw_wx_set_priv(struct net_device *dev,
-- 
2.25.0

Re: [PATCH 4/6] staging: rtl8723bs: Fix potential overuse of kernel memory

[Greg KH]

On Mon, Feb 10, 2020 at 12:02:33PM -0600, Larry Finger wrote:
> In routine wpa_supplicant_ioctl(), the user-controlled p->length is
> checked to be at least the size of struct ieee_param size, but the code
> does not detect the case where p->length is greater than the size
> of the struct, thus a malicious user could be wasting kernel memory.
> Fixes commit 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver").
> 
> Reported by: Pietro Oliva <pietroliva@gmail.com>
> Cc: Pietro Oliva <pietroliva@gmail.com>
> Cc: Stable <stable@vger.kernel.org>
> Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver").
> Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
> -# Please enter the commit message for your changes. Lines starting
> ---

Funny line :)

I'll go edit it...

thanks,

greg k-h