In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: mld: stop TX during firmware restart
When iwlwifi firmware crashes (e.g., NMI_INTERRUPT_UNKNOWN on Intel
BE201/Wi-Fi 7), iwl_mld_nic_error() sets mld->fw_status.in_hw_restart
to true. However, iwl_mld_tx_from_txq() does not check this flag before
dequeuing frames from mac80211 and pushing them to the transport layer.
Since the firmware is dead, iwl_trans_tx() returns -EIO for each frame,
which then gets freed immediately. Under high-throughput conditions
(e.g., Tailscale UDP traffic or active SSH sessions), this creates a
tight dequeue-send-fail-free loop that wastes CPU cycles and generates
rapid skb allocation churn, leading to memory pressure from slab
fragmentation.
The RX path already has this guard (iwl_mld_rx_mpdu checks
in_hw_restart at rx.c:1906), and so does the TXQ allocation worker
(iwl_mld_add_txqs_wk at tx.c:156). Add the same guard to
iwl_mld_tx_from_txq() to stop all TX during firmware restart.
Frames left in mac80211's TXQs are naturally drained after restart
completes, when queue reallocation triggers iwl_mld_tx_from_txq()
via iwl_mld_add_txq_list(), or when new upper-layer traffic invokes
wake_tx_queue.
Tested on ASUS Zenbook 14 UX3405CA with Intel BE201 (Wi-Fi 7) on
kernel 6.19.5 where the firmware crashes approximately every 10-15
minutes under Tailscale traffic.
References
Configurations
No configuration.
History
20 Jul 2026, 15:17
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.5 |
19 Jul 2026, 16:17
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-07-19 16:17
Updated : 2026-07-20 15:17
NVD link : CVE-2026-64175
Mitre link : CVE-2026-64175
CVE.ORG link : CVE-2026-64175
JSON object : View
Products Affected
No product.
CWE
No CWE.