{"id":"CVE-2026-98262","summary":"ata: libahci: clear PxCLBU and PxFBU for AHCI_HFLAG_32BIT_ONLY","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nata: libahci: clear PxCLBU and PxFBU for AHCI_HFLAG_32BIT_ONLY\n\nA user reported that commit 105c42566a55 (\"ata: ahci: force 32-bit DMA for\nJMicron JMB582/JMB585\") made the JMicron JMB585 unusable on his board.\n\nThe failure is seen as soon as the ahci driver is probed, and booting with\niommu=off does not solve the problem.\n\nLooking at the AHCI specification, PxCLBU and PxFBU are both read only '0'\nfor HBAs that do not support 64-bit addressing.\n\nFor HBAs that do support 64-bit addressing, the registers are read write,\nwith a reset value that is Implementation Specific.\n\nWhen using the AHCI_HFLAG_32BIT_ONLY flag, the HBA does support 64-bit\naddressing, and a 32-bit DMA mask is set by simply clearing HOST_CAP_64.\nThus, in this case, we need to explicitly clear the registers to 0.","modified":"2026-10-07T02:47:33.792970008Z","published":"2026-10-06T08:45:26.118Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98262.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/0191c9ff23ef1678dbfb5ad253a2dee92feb5d71"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4719424bb7cb9f20b73986bcb72dd528f0e5c6eb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7912ad8fb5233bb8cfe21d50df639c7f4854ff9d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/82e47533221d4746947b74d2e79a478c36c6433a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8f510f68208a1f673d7c7234a687be4671490e9c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a5a8b4737f68bbac8aa0685af0c8921e6003c22b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b28a17d4a9bb0aa38b48681c3927b012ba40eabe"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b691a3e244278362e552439d6d3ee5a5d3703488"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98262.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98262"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"c7a42156d99bcea7f8173ba7a6034bbaa2ecb77c"},{"fixed":"0191c9ff23ef1678dbfb5ad253a2dee92feb5d71"},{"fixed":"8f510f68208a1f673d7c7234a687be4671490e9c"},{"fixed":"4719424bb7cb9f20b73986bcb72dd528f0e5c6eb"},{"fixed":"a5a8b4737f68bbac8aa0685af0c8921e6003c22b"},{"fixed":"b28a17d4a9bb0aa38b48681c3927b012ba40eabe"},{"fixed":"b691a3e244278362e552439d6d3ee5a5d3703488"},{"fixed":"7912ad8fb5233bb8cfe21d50df639c7f4854ff9d"},{"fixed":"82e47533221d4746947b74d2e79a478c36c6433a"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98262.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.22"},{"fixed":"5.10.271"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.222"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.189"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.158"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.112"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.54"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98262.json"}}],"schema_version":"1.9.0"}