CVE-2026-98827

In the Linux kernel, the following vulnerability has been resolved:

wifi: ath9k htc: bound TX aggregation to MAX TX BUF SIZE

hif usb tx() dequeues up to MAX TX AGGR NUM (20) frames into a single tx buf of MAX TX BUF SIZE (32768) bytes, limiting the batch by record count but never by cumulative byte length.

With large frames (MTU 2304), 20 aggregated frames of 2292 bytes each exceed the allocation (20 * 2296 = 45920 bytes), so the memcpy() in the loop writes up to 13152 bytes past tx buf->buf before usb submit urb().

Peek the queue head and stop before copying any record that would cross MAX TX BUF SIZE, then dispatch the current batch. Leftover skbs remain queued and are drained on the next URB completion.

The byte bound changes the loop's exit semantics: it can now exit before i == tx skb cnt - 1. Stock only finalized tx buf->len on that last index (len += offset), so an early break would submit a URB holding only the last record's length while every dequeued skb is freed on completion, silently dropping frames. Make tx buf->len a running total and advance tx buf->offset per record instead; the stride round up(nskb->len + 4, 4) is identical to the stock stride when the loop runs to completion.

Tested on hardware with an MTU 2304 flood: the loop stops at record 15 (len = 32144, offset = 32144, within 32768), no oversized URB is submitted, and MTU 1500 pings pass 20/20.