AZL-97068

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

net: atlantic: free RX pages of consumed but not refilled buffers

aqringrxdeinit() only walks [swhead, swtail), the region posted to hardware. Since the page reuse strategy was added, a cleaned RX buffer keeps its page (and its DMA mapping) in the ring for reuse, and refill is batched: aqringrxfill() returns early until AQCFGRXREFILLTHRES slots are free. Slots that were consumed but not yet reposted therefore sit in the complementary [swtail, swhead) gap with a live page, and the deinit walk never visits them: up to a refill batch worth of pages and DMA mappings leak on every interface down.

Walk the whole ring instead and release whatever is still there. Also bail out if the buffer ring is already gone: a partial aqptpringalloc() failure frees the ring but leaves aqnic set, so aqptpring_deinit() still gets here on the unwind path.