lkml.org 
[lkml]   [2023]   [Jul]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH v2] wifi: mwifiex: Fix OOB and integer underflow in mwifiex_process_mgmt_packet
Date
Hi, this vulnerability has been reported to and discussed with chromeos teams,
the detail analysis, see comments in below code:
mwifiex_process_sta_rx_packet makes sure rx_pkt_offset + rx_pkt_length <= skb->len
In mwifiex_process_mgmt_packet:

rx_pd = (struct rxpd *)skb->data;

// skb->len -= rx_pkt_offset, skb->len == rx_pkt_length
skb_pull(skb, le16_to_cpu(rx_pd->rx_pkt_offset));
// skb->len == rx_pkt_length - 2, if set rx_pkt_length == 4, skb->len == 2
skb_pull(skb, sizeof(pkt_len));

pkt_len = le16_to_cpu(rx_pd->rx_pkt_length);

//skip..

// now skb->len == 2, skb->data + 24 is oob from skb buffer
// skb->data + 30 is oob from skb buffer
// pkt_len == 4, so underflow
memmove(skb->data + sizeof(struct ieee80211_hdr_3addr),
skb->data + sizeof(struct ieee80211_hdr),
pkt_len - sizeof(struct ieee80211_hdr));

On MT8173 chromebook, the arm64 memmove.S / memcpy.S code logical
cause memove(dst, src, -x) a possible exploitable oob write vulnerability
not only a unexploitable crash

\
 
 \ /
  Last update: 2023-07-10 17:03    [W:0.033 / U:0.800 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site