From 60bdb51d44faf3723aa037e501eb84d500fb4dfd Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 3 Jun 2020 13:19:58 +0300 Subject: [PATCH] Staging: rtl8723bs: prevent buffer overflow in update_sta_support_rate() commit b65a2d8c8614386f7e8d38ea150749f8a862f431 upstream. The "ie_len" variable is in the 0-255 range and it comes from the network. If it's over NDIS_802_11_LENGTH_RATES_EX (16) then that will lead to memory corruption. Fixes: 554c0a3abf21 ("staging: Add rtl8723bs sdio wifi driver") Signed-off-by: Dan Carpenter Cc: stable Link: https://lore.kernel.org/r/20200603101958.GA1845750@mwanda Signed-off-by: Greg Kroah-Hartman --- drivers/staging/rtl8723bs/core/rtw_wlan_util.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/staging/rtl8723bs/core/rtw_wlan_util.c b/drivers/staging/rtl8723bs/core/rtw_wlan_util.c index ea3ea2a..f6678ba 100644 --- a/drivers/staging/rtl8723bs/core/rtw_wlan_util.c +++ b/drivers/staging/rtl8723bs/core/rtw_wlan_util.c @@ -1845,12 +1845,14 @@ int update_sta_support_rate(struct adapter *padapter, u8 *pvar_ie, uint var_ie_l pIE = (struct ndis_80211_var_ie *)rtw_get_ie(pvar_ie, _SUPPORTEDRATES_IE_, &ie_len, var_ie_len); if (!pIE) return _FAIL; + if (ie_len > sizeof(pmlmeinfo->FW_sta_info[cam_idx].SupportedRates)) + return _FAIL; memcpy(pmlmeinfo->FW_sta_info[cam_idx].SupportedRates, pIE->data, ie_len); supportRateNum = ie_len; pIE = (struct ndis_80211_var_ie *)rtw_get_ie(pvar_ie, _EXT_SUPPORTEDRATES_IE_, &ie_len, var_ie_len); - if (pIE) + if (pIE && (ie_len <= sizeof(pmlmeinfo->FW_sta_info[cam_idx].SupportedRates) - supportRateNum)) memcpy((pmlmeinfo->FW_sta_info[cam_idx].SupportedRates + supportRateNum), pIE->data, ie_len); return _SUCCESS; -- 2.7.4