In the Linux kernel, the following vulnerability has been resolved:
wifi: zd1211rw: Fix potential NULL pointer dereference in zd_mac_tx_to_dev()
There is a potential NULL pointer dereference in zd_mac_tx_to_dev(). For
example, the following is possible:
T0 T1
zd_mac_tx_to_dev()
/* len == skb_queue_len(q) */
while (len > ZD_MAC_MAX_ACK_WAITERS) {
filter_ack()
spin_lock_irqsave(&q->lock, flags);
/* position == skb_queue_len(q) */
for (i=1; i<position; i++)
skb = __skb_dequeue(q)
if (mac->type == NL80211_IFTYPE_AP)
skb = __skb_dequeue(q);
spin_unlock_irqrestore(&q->lock, flags);
skb_dequeue() -> NULL
Since there is a small gap between checking skb queue length and skb being
unconditionally dequeued in zd_mac_tx_to_dev(), skb_dequeue() can return NULL.
Then the pointer is passed to zd_mac_tx_status() where it is dereferenced.
In order to avoid potential NULL pointer dereference due to situations like
above, check if skb is not NULL before passing it to zd_mac_tx_status().
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Metrics
Affected Vendors & Products
References
History
Mon, 18 Aug 2025 21:00:00 +0000
Type | Values Removed | Values Added |
---|---|---|
First Time appeared |
Linux
Linux linux Kernel |
|
Vendors & Products |
Linux
Linux linux Kernel |
Sat, 16 Aug 2025 11:15:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Description | In the Linux kernel, the following vulnerability has been resolved: wifi: zd1211rw: Fix potential NULL pointer dereference in zd_mac_tx_to_dev() There is a potential NULL pointer dereference in zd_mac_tx_to_dev(). For example, the following is possible: T0 T1 zd_mac_tx_to_dev() /* len == skb_queue_len(q) */ while (len > ZD_MAC_MAX_ACK_WAITERS) { filter_ack() spin_lock_irqsave(&q->lock, flags); /* position == skb_queue_len(q) */ for (i=1; i<position; i++) skb = __skb_dequeue(q) if (mac->type == NL80211_IFTYPE_AP) skb = __skb_dequeue(q); spin_unlock_irqrestore(&q->lock, flags); skb_dequeue() -> NULL Since there is a small gap between checking skb queue length and skb being unconditionally dequeued in zd_mac_tx_to_dev(), skb_dequeue() can return NULL. Then the pointer is passed to zd_mac_tx_status() where it is dereferenced. In order to avoid potential NULL pointer dereference due to situations like above, check if skb is not NULL before passing it to zd_mac_tx_status(). Found by Linux Verification Center (linuxtesting.org) with SVACE. | |
Title | wifi: zd1211rw: Fix potential NULL pointer dereference in zd_mac_tx_to_dev() | |
References |
|
|

Status: PUBLISHED
Assigner: Linux
Published: 2025-08-16T10:55:00.254Z
Updated: 2025-08-16T10:55:00.254Z
Reserved: 2025-04-16T04:51:24.023Z
Link: CVE-2025-38513

No data.

Status : Awaiting Analysis
Published: 2025-08-16T11:15:44.383
Modified: 2025-08-18T20:16:28.750
Link: CVE-2025-38513

No data.