mwifiex_update_bss_desc_with_ie() records raw pointers to the HT Capabilities, HT Operation, VHT Capabilities, VHT Operation, 20/40 BSS Coexistence and Operating Mode Notification elements taken straight out of a beacon/probe-response buffer, without checking that each element is long enough for the fixed-size structure that later consumers read. The buffer is a tight kmemdup() of the on-air IEs (beacon_buf_size == ies->len), so a truncated element placed last leaves the stored pointer one past the end of the allocation. At association time these pointers are dereferenced at fixed offsets regardless of the on-air length: mwifiex_cmd_append_11n_tlv() memcpy()s sizeof(struct ieee80211_ht_cap) (26 bytes) from bcn_ht_cap and reads bcn_ht_oper->ht_param, and mwifiex_cmd_append_11ac_tlv() memcpy()s sizeof(struct ieee80211_vht_cap) (12 bytes) from bcn_vht_cap and reads bcn_vht_oper->chan_width. A nearby AP (rogue / evil-twin; an open SSID needs no credentials) advertising a BSS with a truncated HT/VHT cap element therefore triggers a slab out-of-bounds read on the victim's association attempt. This out-of-bounds read is the primary issue. For the HT-Cap copy the over-read bytes are additionally placed into the outgoing association request, so a limited amount of adjacent heap memory can leak over the air. In station mode this is small (single-digit bytes), because mwifiex_fill_cap_info() rewrites most of the copied HT-Cap before transmission; the leak is a secondary effect. mwifiex_set_sta_ht_cap() has the same missing-length pattern: in uAP mode it reads two bytes of ieee80211_ht_cap.cap_info from a cfg80211_find_ie(WLAN_EID_HT_CAPABILITY) result in a client association request without checking the element length, a 1-2 byte out-of-bounds read (used only to select an A-MSDU size, not leaked). Reject (skip) any of these elements whose payload is shorter than the structure the driver later reads, matching the length validation the FH/DS/CF/IBSS parameter-set cases in the same beacon parser already perform. No dynamic reproducer: mwifiex is a fullmac driver for Marvell hardware with no mac80211_hwsim equivalent, so this was confirmed by source and structure-offset analysis only. Found by 0sec automated security-research tooling (https://0sec.ai). Fixes: 5e6e3a92b9a4 ("wireless: mwifiex: initial commit for Marvell mwifiex driver") Cc: stable@vger.kernel.org Assisted-by: 0sec:claude-opus-4-8 Signed-off-by: Doruk Tan Ozturk --- drivers/net/wireless/marvell/mwifiex/scan.c | 12 ++++++++++++ drivers/net/wireless/marvell/mwifiex/util.c | 2 +- 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/marvell/mwifiex/scan.c b/drivers/net/wireless/marvell/mwifiex/scan.c index 97c0ec3b822e..997e7e19525b 100644 --- a/drivers/net/wireless/marvell/mwifiex/scan.c +++ b/drivers/net/wireless/marvell/mwifiex/scan.c @@ -1384,6 +1384,8 @@ int mwifiex_update_bss_desc_with_ie(struct mwifiex_adapter *adapter, bss_entry->beacon_buf); break; case WLAN_EID_HT_CAPABILITY: + if (element_len < sizeof(struct ieee80211_ht_cap)) + break; bss_entry->bcn_ht_cap = (struct ieee80211_ht_cap *) (current_ptr + sizeof(struct ieee_types_header)); @@ -1392,6 +1394,8 @@ int mwifiex_update_bss_desc_with_ie(struct mwifiex_adapter *adapter, bss_entry->beacon_buf); break; case WLAN_EID_HT_OPERATION: + if (element_len < sizeof(struct ieee80211_ht_operation)) + break; bss_entry->bcn_ht_oper = (struct ieee80211_ht_operation *)(current_ptr + sizeof(struct ieee_types_header)); @@ -1400,6 +1404,8 @@ int mwifiex_update_bss_desc_with_ie(struct mwifiex_adapter *adapter, bss_entry->beacon_buf); break; case WLAN_EID_VHT_CAPABILITY: + if (element_len < sizeof(struct ieee80211_vht_cap)) + break; bss_entry->disable_11ac = false; bss_entry->bcn_vht_cap = (void *)(current_ptr + @@ -1409,6 +1415,8 @@ int mwifiex_update_bss_desc_with_ie(struct mwifiex_adapter *adapter, bss_entry->beacon_buf); break; case WLAN_EID_VHT_OPERATION: + if (element_len < sizeof(struct ieee80211_vht_operation)) + break; bss_entry->bcn_vht_oper = (void *)(current_ptr + sizeof(struct ieee_types_header)); @@ -1417,6 +1425,8 @@ int mwifiex_update_bss_desc_with_ie(struct mwifiex_adapter *adapter, bss_entry->beacon_buf); break; case WLAN_EID_BSS_COEX_2040: + if (!element_len) + break; bss_entry->bcn_bss_co_2040 = current_ptr; bss_entry->bss_co_2040_offset = (u16) (current_ptr - bss_entry->beacon_buf); @@ -1427,6 +1437,8 @@ int mwifiex_update_bss_desc_with_ie(struct mwifiex_adapter *adapter, (u16) (current_ptr - bss_entry->beacon_buf); break; case WLAN_EID_OPMODE_NOTIF: + if (!element_len) + break; bss_entry->oper_mode = (void *)current_ptr; bss_entry->oper_mode_offset = (u16)((u8 *)bss_entry->oper_mode - diff --git a/drivers/net/wireless/marvell/mwifiex/util.c b/drivers/net/wireless/marvell/mwifiex/util.c index 7d3631d21223..844223c04e2e 100644 --- a/drivers/net/wireless/marvell/mwifiex/util.c +++ b/drivers/net/wireless/marvell/mwifiex/util.c @@ -721,7 +721,7 @@ mwifiex_set_sta_ht_cap(struct mwifiex_private *priv, const u8 *ies, ht_cap_ie = (void *)cfg80211_find_ie(WLAN_EID_HT_CAPABILITY, ies, ies_len); - if (ht_cap_ie) { + if (ht_cap_ie && ht_cap_ie->len >= sizeof(struct ieee80211_ht_cap)) { ht_cap = (void *)(ht_cap_ie + 1); node->is_11n_enabled = 1; node->max_amsdu = le16_to_cpu(ht_cap->cap_info) & -- 2.43.0