[PATCH 4.19 123/131] Staging: rtl8723bs: prevent buffer overflow in update_sta_support_rate()
From: Sasha Levin <sashal@kernel.org>
Date: 2020-06-29 20:09:51
Also in:
stable
Subsystem:
staging subsystem, the rest · Maintainers:
Greg Kroah-Hartman, Linus Torvalds
From: Dan Carpenter <redacted>
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 <redacted>
Cc: stable <redacted>
Link: https://lore.kernel.org/r/20200603101958.GA1845750@mwanda (local)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
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 2c65af319a604..6c6bf03ac38aa 100644
--- a/drivers/staging/rtl8723bs/core/rtw_wlan_util.c
+++ b/drivers/staging/rtl8723bs/core/rtw_wlan_util.c@@ -1856,12 +1856,14 @@ 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;
--
2.25.1