From 41eedf39dfb145fb8fa04cd5b799f7bdc7679696 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 1 Mar 2012 10:02:08 +0300 Subject: [PATCH] rndis_wlan: integer overflows in rndis_wlan_do_link_up_work() If "offset" is negative then we can get past this check: if (offset > CONTROL_BUFFER_SIZE) Or if we pick a very high "req_ie_len" then we can get around the check: if (offset + req_ie_len > CONTROL_BUFFER_SIZE) I made "resp_ie_len" and "req_ie_len" unsigned. I don't know if it was intentional that they were signed in the original. Signed-off-by: Dan Carpenter Acked-by: Jussi Kivilinna Signed-off-by: John W. Linville --- drivers/net/wireless/rndis_wlan.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/rndis_wlan.c b/drivers/net/wireless/rndis_wlan.c index a330c69..dde45ef 100644 --- a/drivers/net/wireless/rndis_wlan.c +++ b/drivers/net/wireless/rndis_wlan.c @@ -2755,9 +2755,10 @@ static void rndis_wlan_do_link_up_work(struct usbnet *usbdev) struct rndis_wlan_private *priv = get_rndis_wlan_priv(usbdev); struct ndis_80211_assoc_info *info = NULL; u8 bssid[ETH_ALEN]; - int resp_ie_len, req_ie_len; + unsigned int resp_ie_len, req_ie_len; + unsigned int offset; u8 *req_ie, *resp_ie; - int ret, offset; + int ret; bool roamed = false; bool match_bss; @@ -2785,7 +2786,9 @@ static void rndis_wlan_do_link_up_work(struct usbnet *usbdev) ret = get_association_info(usbdev, info, CONTROL_BUFFER_SIZE); if (!ret) { req_ie_len = le32_to_cpu(info->req_ie_length); - if (req_ie_len > 0) { + if (req_ie_len > CONTROL_BUFFER_SIZE) + req_ie_len = CONTROL_BUFFER_SIZE; + if (req_ie_len != 0) { offset = le32_to_cpu(info->offset_req_ies); if (offset > CONTROL_BUFFER_SIZE) @@ -2799,7 +2802,9 @@ static void rndis_wlan_do_link_up_work(struct usbnet *usbdev) } resp_ie_len = le32_to_cpu(info->resp_ie_length); - if (resp_ie_len > 0) { + if (resp_ie_len > CONTROL_BUFFER_SIZE) + resp_ie_len = CONTROL_BUFFER_SIZE; + if (resp_ie_len != 0) { offset = le32_to_cpu(info->offset_resp_ies); if (offset > CONTROL_BUFFER_SIZE) -- 2.7.4