{"id":17365,"date":"2026-09-05T02:31:02","date_gmt":"2026-09-04T18:31:02","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-80861"},"modified":"2026-09-05T02:31:02","modified_gmt":"2026-09-04T18:31:02","slug":"cve-2026-80861","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-80861","title":{"rendered":"CVE-2026-80861 &#8211; In the Linux kernel, the following vulnerability has been resolved:\n\nusb: xhci: bail out o"},"content":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>usb: xhci: bail out of setup if the controller is inaccessible<\/p>\n<p>xhci_gen_setup() locates the operational registers using the capability<br \/>\nlength read from the very first register:<\/p>\n<p>\txhci-&gt;op_regs = hcd-&gt;regs +<br \/>\n\t\tHC_LENGTH(readl(&amp;xhci-&gt;cap_regs-&gt;hc_capbase));<\/p>\n<p>If the controller is dead or has dropped off the bus, that read returns<br \/>\n~0, HC_LENGTH() truncates it to 0xff, and op_regs ends up 0xff bytes<br \/>\npast the page-aligned MMIO base, i.e. unaligned. The first access<br \/>\nthrough it, xhci_halt() -&gt; xhci_handshake() reading op_regs-&gt;status, is<br \/>\nthen an unaligned readl() on device memory. arm64 faults on unaligned<br \/>\ndevice accesses, so instead of xhci_handshake() catching the all-ones<br \/>\nvalue and returning -ENODEV, setup oopses:<\/p>\n<p>  xhci-pci-renesas 0005:08:00.0: Unable to change power state from D3cold to D0, device inaccessible<br \/>\n  xhci-pci-renesas 0005:08:00.0: xHCI Host Controller<br \/>\n  xhci-pci-renesas 0005:08:00.0: new USB bus registered, assigned bus number 1<br \/>\n  Unable to handle kernel paging request at virtual address ffff80030a770103<br \/>\n    ESR = 0x0000000096000021<br \/>\n    FSC = 0x21: alignment fault<br \/>\n  Internal error: Oops: 0000000096000021 [#1]  SMP<br \/>\n  pc : xhci_halt [xhci_hcd]<br \/>\n  Call trace:<br \/>\n   xhci_halt<br \/>\n   xhci_gen_setup<br \/>\n   xhci_pci_setup<br \/>\n   usb_add_hcd<br \/>\n   usb_hcd_pci_probe<br \/>\n   xhci_pci_common_probe<br \/>\n   xhci_pci_renesas_probe<\/p>\n<p>This was hit with a Renesas uPD720201 that failed to power up (&#8220;Unable<br \/>\nto change power state from D3cold to D0, device inaccessible&#8221;) yet still<br \/>\nreached the HCD probe path.<\/p>\n<p>Read the capability register once, and if it reads back the all-ones<br \/>\nvalue (as xhci_handshake() and xhci_reset() already test for), abort<br \/>\nsetup with -ENODEV before op_regs is derived from it. Reading it once<br \/>\nalso avoids re-reading a register that may change under a concurrent<br \/>\nhot-removal.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>usb: xhci: bail out of setup if the controller is inaccessible<\/p>\n<p>xhci_gen_setup() locates the operational registers using the capabi<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-17365","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/17365","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=17365"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=17365"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=17365"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}