{"id":21267,"date":"2026-09-12T04:30:57","date_gmt":"2026-09-11T20:30:57","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-80934"},"modified":"2026-09-12T04:30:57","modified_gmt":"2026-09-11T20:30:57","slug":"cve-2026-80934","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-80934","title":{"rendered":"CVE-2026-80934 &#8211; In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mt76: mt7996: f"},"content":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>wifi: mt76: mt7996: fix TX DMA mapping leak for AddBA req frames<\/p>\n<p>mt7996\/mt7992 hand the firmware a HW MAC-TXP for AddBA req action frames<br \/>\n(MT_TXD7_MAC_TXD, set in mt7996_mac_write_txwi_80211()), but are otherwise<br \/>\nFW-TXP devices. On tx free mt76_connac_txp_skb_unmap() therefore decodes<br \/>\nthe per-frame txp as a struct mt76_connac_fw_txp. For a MAC-TXP the<br \/>\nfw_txp.nbuf byte aliases the AddBA TID word (MT_TXP1_TID_ADDBA), which is<br \/>\nalways zero, so the unmap loop runs zero times and the skb DMA mapping in<br \/>\nbuf[1] is never unmapped. buf[1].skip_unmap is set unconditionally, so the<br \/>\ngeneric DMA-ring cleanup skips it as well.<\/p>\n<p>Each AddBA req therefore leaks one TX DMA mapping, roughly one per<br \/>\n(re)association. With WED enabled these mappings are bounced through the<br \/>\nWED swiotlb pool, so under continuous client reconnect churn the pool is<br \/>\nexhausted after ~1-2 days, after which DMA mapping fails for WED, the WiFi<br \/>\nMCU and other on-SoC consumers.<\/p>\n<p>Keep the deferred (token release) unmap that the design relies on, and add<br \/>\nan mt7996-specific txp unmap that inspects MT_TXD7_MAC_TXD and unmaps<br \/>\nbuf[1] from the MAC-TXP layout for those frames, delegating to<br \/>\nmt76_connac_txp_skb_unmap() otherwise.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>wifi: mt76: mt7996: fix TX DMA mapping leak for AddBA req frames<\/p>\n<p>mt7996\/mt7992 hand the firmware a HW MAC-TXP for AddBA req action<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-21267","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/21267","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=21267"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21267"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21267"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}