{"id":"CVE-2026-80825","revision":"121cf6eb1c6c4d809c8bef61b24a076e","records":[{"revision":"121cf6eb1c6c4d809c8bef61b24a076e","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-80825","aliases":[],"title":"wifi: mt76: mt7925: ensure tx headroom in usb_sdio_tx_prepare_skb","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mt76: mt7925: ensure tx headroom in usb_sdio_tx_prepare_skb\n\nmt7925_usb_sdio_tx_prepare_skb() pushes a TX descriptor and a USB\nheader onto every skb and assumes the headroom for them is already\nthere. That holds for locally generated traffic, where mac80211\nreserves hw->extra_tx_headroom, but forwarded frames are sent through\nieee80211_8023_xmit(), which does not reserve it. Bridge a wired\ninterface to an mt7925u AP and the first forwarded frame that arrives\nshort panics the kernel:\n\n skbuff: skb_under_panic: len:415 put:4 tail:0x19b end:0x640 dev:wlan1\n kernel BUG at net/core/skbuff.c:212!\n Call trace:\n  skb_panic+0x58/0x60 (P)\n  skb_push+0x58/0x60\n  mt7925_usb_sdio_tx_prepare_skb+0xf8/0x1b8 [mt7925_common]\n  mt76u_tx_queue_skb+0xa0/0x1f8 [mt76_usb]\n  __mt76_tx_queue_skb+0x54/0xe8 [mt76]\n  mt76_txq_schedule.part.0+0x204/0x478 [mt76]\n  mt76_txq_schedule_all+0x50/0x80 [mt76]\n  mt792x_tx_worker+0x68/0x100 [mt792x_lib]\n  __mt76_worker_fn+0x84/0x150 [mt76]\n\nWhether a given setup hits it depends on how much headroom the ingress\nnetdev leaves in its rx skbs. Reproduced on a Raspberry Pi 5 bridging\nonboard ethernet to a Netgear A9000; originally reported on an MT7986\nrouter running OpenWrt. Nick Morrow's testing on a Pi 4 (bcmgenet),\nwhich leaves more headroom, helped narrow the trigger to the ingress\npath.\n\nThe same bug was fixed on mt7921 by commit 98c4d0abf5c4 (\"mt76:\nmt7921: don't assume adequate headroom for SDIO headers\"), but mt7925\nwas copied from mt7921 without the fix. Add the same guard here.","state":0,"publishedAt":"2026-09-04T15:54:29.224+00:00","modifiedAt":"2026-10-19T08:44:17.799+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/net/wireless/mediatek/mt76/mt7925/mac.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"c948b5da6bbec742b433138e3e3f9537a85af2e5\",\n                            \"lessThan\": \"9a72b180f0575e41471e088e09bddc4b73d6dee2\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c948b5da6bbec742b433138e3e3f9537a85af2e5\",\n                            \"lessThan\": \"22edb6786127271aeba7abd30f152977c605c6a3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c948b5da6bbec742b433138e3e3f9537a85af2e5\",\n                            \"lessThan\": \"8d481f93588932a95f657671d4e1601b90d130cc\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c948b5da6bbec742b433138e3e3f9537a85af2e5\",\n                            \"lessThan\": \"e5e8fc11a7ac578f16079f855b7fffc1649d053c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c948b5da6bbec742b433138e3e3f9537a85af2e5\",\n                            \"lessThan\": \"ef3e34874d2332d0f63e72c2c35ce5c93568c125\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/net/wireless/mediatek/mt76/mt7925/mac.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.7\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.7\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.108\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.49\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.13\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.3\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/9a72b180f0575e41471e088e09bddc4b73d6dee2","https://git.kernel.org/stable/c/22edb6786127271aeba7abd30f152977c605c6a3","https://git.kernel.org/stable/c/8d481f93588932a95f657671d4e1601b90d130cc","https://git.kernel.org/stable/c/e5e8fc11a7ac578f16079f855b7fffc1649d053c","https://git.kernel.org/stable/c/ef3e34874d2332d0f63e72c2c35ce5c93568c125"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-80825","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-80825","identifiers":["CVE-2026-80825"]},"retained":false,"historicalAffected":[]}],"coverage":[]}