This is a note to let you know that I've just added the patch titled Staging: rtl8723bs: prevent buffer overflow in update_sta_support_rate() to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: staging-rtl8723bs-prevent-buffer-overflow-in-update_sta_support_rate.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From b65a2d8c8614386f7e8d38ea150749f8a862f431 Mon Sep 17 00:00:00 2001 From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Date: Wed, 3 Jun 2020 13:19:58 +0300 Subject: Staging: rtl8723bs: prevent buffer overflow in update_sta_support_rate() From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> 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 <dan.carpenter@xxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200603101958.GA1845750@mwanda Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/rtl8723bs/core/rtw_wlan_util.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/staging/rtl8723bs/core/rtw_wlan_util.c +++ b/drivers/staging/rtl8723bs/core/rtw_wlan_util.c @@ -1904,12 +1904,14 @@ int update_sta_support_rate(struct adapt pIE = (struct ndis_80211_var_ie *)rtw_get_ie(pvar_ie, _SUPPORTEDRATES_IE_, &ie_len, var_ie_len); if (pIE == NULL) 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; Patches currently in stable-queue which might be from dan.carpenter@xxxxxxxxxx are queue-4.14/staging-rtl8723bs-prevent-buffer-overflow-in-update_sta_support_rate.patch queue-4.14/mm-slab-use-memzero_explicit-in-kzfree.patch queue-4.14/usb-gadget-udc-potential-oops-in-error-handling-code.patch