4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arend Van Spriel <arend.vanspriel@xxxxxxxxxxxx> commit ded89912156b1a47d940a0c954c43afbabd0c42c upstream. User-space can choose to omit NL80211_ATTR_SSID and only provide raw IE TLV data. When doing so it can provide SSID IE with length exceeding the allowed size. The driver further processes this IE copying it into a local variable without checking the length. Hence stack can be corrupted and used as exploit. Reported-by: Daxing Guo <freener.gdx@xxxxxxxxx> Reviewed-by: Hante Meuleman <hante.meuleman@xxxxxxxxxxxx> Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@xxxxxxxxxxxx> Reviewed-by: Franky Lin <franky.lin@xxxxxxxxxxxx> Signed-off-by: Arend van Spriel <arend.vanspriel@xxxxxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Signed-off-by: Juerg Haefliger <juerg.haefliger@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/brcm80211/brcmfmac/cfg80211.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/wireless/brcm80211/brcmfmac/cfg80211.c +++ b/drivers/net/wireless/brcm80211/brcmfmac/cfg80211.c @@ -4102,7 +4102,7 @@ brcmf_cfg80211_start_ap(struct wiphy *wi (u8 *)&settings->beacon.head[ie_offset], settings->beacon.head_len - ie_offset, WLAN_EID_SSID); - if (!ssid_ie) + if (!ssid_ie || ssid_ie->len > IEEE80211_MAX_SSID_LEN) return -EINVAL; memcpy(ssid_le.SSID, ssid_ie->data, ssid_ie->len); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html