From: Dan Carpenter Date: Mon, 3 Feb 2014 22:38:35 +0000 (+0300) Subject: staging: r8188eu: overflow in rtw_p2p_get_go_device_address() X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e6ff3f4e6d258021fe041d7acf5d013c26bf387b;p=linux-beck.git staging: r8188eu: overflow in rtw_p2p_get_go_device_address() The go_devadd_str[] array is two characters too small to hold the address so we corrupt memory. I've changed the user space API slightly and I don't have a way to test if this breaks anything. In the original code we truncated away the last digit of the address and the NUL terminator so it was already a bit broken. Signed-off-by: Dan Carpenter Acked-by: Larry Finger Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c b/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c index 684bc8107a48..4ad80ae1067f 100644 --- a/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c +++ b/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c @@ -3164,9 +3164,7 @@ static int rtw_p2p_get_go_device_address(struct net_device *dev, u8 *p2pie; uint p2pielen = 0, attr_contentlen = 0; u8 attr_content[100] = {0x00}; - - u8 go_devadd_str[17 + 10] = {0x00}; - /* +10 is for the str "go_devadd =", we have to clear it at wrqu->data.pointer */ + u8 go_devadd_str[17 + 12] = {}; /* Commented by Albert 20121209 */ /* The input data is the GO's interface address which the application wants to know its device address. */ @@ -3223,12 +3221,12 @@ static int rtw_p2p_get_go_device_address(struct net_device *dev, spin_unlock_bh(&pmlmepriv->scanned_queue.lock); if (!blnMatch) - sprintf(go_devadd_str, "\n\ndev_add = NULL"); + snprintf(go_devadd_str, sizeof(go_devadd_str), "\n\ndev_add = NULL"); else - sprintf(go_devadd_str, "\n\ndev_add =%.2X:%.2X:%.2X:%.2X:%.2X:%.2X", + snprintf(go_devadd_str, sizeof(go_devadd_str), "\n\ndev_add =%.2X:%.2X:%.2X:%.2X:%.2X:%.2X", attr_content[0], attr_content[1], attr_content[2], attr_content[3], attr_content[4], attr_content[5]); - if (copy_to_user(wrqu->data.pointer, go_devadd_str, 10 + 17)) + if (copy_to_user(wrqu->data.pointer, go_devadd_str, sizeof(go_devadd_str))) return -EFAULT; return ret; }