Commit d4ac6403 authored by Dan Carpenter's avatar Dan Carpenter Committed by Greg Kroah-Hartman
Browse files

staging: rtl8188eu: fix potential memory corruption in rtw_check_beacon_data() 



The "ie_len" is a value in the 1-255 range that comes from the user.  We
have to cap it to ensure that it's not too large or it could lead to
memory corruption.

Fixes: 9a7fe54d ("staging: r8188eu: Add source files for new driver - part 1")
Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/YEHyQCrFZKTXyT7J@mwanda


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 87107518

drivers/staging/rtl8188eu/core/rtw_ap.c

+5 −0
Original line number Diff line number Diff line
@@ -791,6 +791,7 @@ int rtw_check_beacon_data(struct adapter *padapter, u8 *pbuf, int len) 
	p = rtw_get_ie(ie + _BEACON_IE_OFFSET_, WLAN_EID_SSID, &ie_len,

		       pbss_network->ie_length - _BEACON_IE_OFFSET_);

	if (p && ie_len > 0) {

		ie_len = min_t(int, ie_len, sizeof(pbss_network->ssid.ssid));

		memset(&pbss_network->ssid, 0, sizeof(struct ndis_802_11_ssid));

		memcpy(pbss_network->ssid.ssid, p + 2, ie_len);

		pbss_network->ssid.ssid_length = ie_len;
@@ -811,6 +812,7 @@ int rtw_check_beacon_data(struct adapter *padapter, u8 *pbuf, int len) 
	p = rtw_get_ie(ie + _BEACON_IE_OFFSET_, WLAN_EID_SUPP_RATES, &ie_len,

		       pbss_network->ie_length - _BEACON_IE_OFFSET_);

	if (p) {

		ie_len = min_t(int, ie_len, NDIS_802_11_LENGTH_RATES_EX);

		memcpy(supportRate, p + 2, ie_len);

		supportRateNum = ie_len;

	}
@@ -819,6 +821,8 @@ int rtw_check_beacon_data(struct adapter *padapter, u8 *pbuf, int len) 
	p = rtw_get_ie(ie + _BEACON_IE_OFFSET_, WLAN_EID_EXT_SUPP_RATES,

		       &ie_len, pbss_network->ie_length - _BEACON_IE_OFFSET_);

	if (p) {

		ie_len = min_t(int, ie_len,

			       NDIS_802_11_LENGTH_RATES_EX - supportRateNum);

		memcpy(supportRate + supportRateNum, p + 2, ie_len);

		supportRateNum += ie_len;

	}
@@ -934,6 +938,7 @@ int rtw_check_beacon_data(struct adapter *padapter, u8 *pbuf, int len) 


		pht_cap->mcs.rx_mask[0] = 0xff;

		pht_cap->mcs.rx_mask[1] = 0x0;

		ie_len = min_t(int, ie_len, sizeof(pmlmepriv->htpriv.ht_cap));

		memcpy(&pmlmepriv->htpriv.ht_cap, p + 2, ie_len);

	}