From: Ganapathi Bhat gbhat@marvell.com
[ Upstream commit 3d94a4a8373bf5f45cf5f939e88b8354dbf2311b ]
mwifiex_process_country_ie() function parse elements of bss descriptor in beacon packet. When processing WLAN_EID_COUNTRY element, there is no upper limit check for country_ie_len before calling memcpy. The destination buffer domain_info->triplet is an array of length MWIFIEX_MAX_TRIPLET_802_11D(83). The remote attacker can build a fake AP with the same ssid as real AP, and send malicous beacon packet with long WLAN_EID_COUNTRY elemen (country_ie_len > 83). Attacker can force STA connect to fake AP on a different channel. When the victim STA connects to fake AP, will trigger the heap buffer overflow. Fix this by checking for length and if found invalid, don not connect to the AP.
This fix addresses CVE-2019-14895.
Reported-by: huangwen huangwenabc@gmail.com Signed-off-by: Ganapathi Bhat gbhat@marvell.com Signed-off-by: Kalle Valo kvalo@codeaurora.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/marvell/mwifiex/sta_ioctl.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/marvell/mwifiex/sta_ioctl.c b/drivers/net/wireless/marvell/mwifiex/sta_ioctl.c index a8043d76152a..f88a953b3cd5 100644 --- a/drivers/net/wireless/marvell/mwifiex/sta_ioctl.c +++ b/drivers/net/wireless/marvell/mwifiex/sta_ioctl.c @@ -271,6 +271,14 @@ static int mwifiex_process_country_ie(struct mwifiex_private *priv, "11D: skip setting domain info in FW\n"); return 0; } + + if (country_ie_len > + (IEEE80211_COUNTRY_STRING_LEN + MWIFIEX_MAX_TRIPLET_802_11D)) { + mwifiex_dbg(priv->adapter, ERROR, + "11D: country_ie_len overflow!, deauth AP\n"); + return -EINVAL; + } + memcpy(priv->adapter->country_code, &country_ie[2], 2);
domain_info->country_code[0] = country_ie[2]; @@ -314,8 +322,9 @@ int mwifiex_bss_start(struct mwifiex_private *priv, struct cfg80211_bss *bss, priv->scan_block = false;
if (bss) { - if (adapter->region_code == 0x00) - mwifiex_process_country_ie(priv, bss); + if (adapter->region_code == 0x00 && + mwifiex_process_country_ie(priv, bss)) + return -EINVAL;
/* Allocate and fill new bss descriptor */ bss_desc = kzalloc(sizeof(struct mwifiex_bssdescriptor),