From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> commit d4ac640322b06095128a5c45ba4a1e80929fe7f3 upstream. 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: 9a7fe54ddc3a ("staging: r8188eu: Add source files for new driver - part 1") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/YEHyQCrFZKTXyT7J@mwanda Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/rtl8188eu/core/rtw_ap.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/staging/rtl8188eu/core/rtw_ap.c +++ b/drivers/staging/rtl8188eu/core/rtw_ap.c @@ -791,6 +791,7 @@ int rtw_check_beacon_data(struct adapter p = rtw_get_ie(ie + _BEACON_IE_OFFSET_, _SSID_IE_, &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 p = rtw_get_ie(ie + _BEACON_IE_OFFSET_, _SUPPORTEDRATES_IE_, &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 p = rtw_get_ie(ie + _BEACON_IE_OFFSET_, _EXT_SUPPORTEDRATES_IE_, &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 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); }