{"id":"CVE-2026-74472","summary":"ublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()\n\nublk_ctrl_add_dev() memcpy()s the userspace ublksrv_ctrl_dev_info into\nub-\u003edev_info and then fixes up the fields the driver owns, but misses\n-\u003estate and -\u003eublksrv_pid.\n\nA device added with -\u003estate = UBLK_S_DEV_LIVE passes the\n\"-\u003estate != UBLK_S_DEV_DEAD\" test that ublk_stop_dev_unlocked() uses as its\nproxy for \"a disk is attached\", while -\u003eub_disk is still NULL, so DEL_DEV\nright after ADD_DEV oopses in del_gendisk().  UBLK_S_DEV_QUIESCED plus\nUBLK_F_USER_RECOVERY dies one step earlier, in ublk_force_abort_dev().  A\npoisoned -\u003estate also gets START_USER_RECOVERY and the char device\nread/write path onto a device that was never started, and wedges START_DEV\nat -EEXIST.  A poisoned -\u003eublksrv_pid just makes GET_DEV_INFO report an\nunrelated task as the ublk server.\n\nReset both after the memcpy(), as ublk_detach_disk() does.  Userspace only\never reads these back, so correcting them silently breaks nothing.\n\nADD_DEV has copied -\u003estate in unsanitized since ublk was merged, but back\nthen it was harmless: the gendisk was allocated during ADD_DEV, and both\nteardown and the START_DEV -EEXIST check keyed off disk_live() rather than\n-\u003estate.  The oops became reachable once the disk allocation moved to\nSTART_DEV and those checks switched to -\u003estate.","modified":"2026-08-18T03:31:23.101593201Z","published":"2026-08-15T12:27:08.759Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74472.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/127033b79383a3e78361d7e971588aa8849f5124"},{"type":"WEB","url":"https://git.kernel.org/stable/c/205feb72e5beb3140e4e1403b6cff30cf739bab9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b67ce16b26ad0f14cfd6071013840aa95f823bea"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e65848e4ce352bac9e3465099354c8b8f845391f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ee41b00858ca65b4428e99efe39a4277c1f043d2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74472.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74472"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6d9e6dfdf3b207701471f364121c67eefb000682"},{"fixed":"ee41b00858ca65b4428e99efe39a4277c1f043d2"},{"fixed":"b67ce16b26ad0f14cfd6071013840aa95f823bea"},{"fixed":"205feb72e5beb3140e4e1403b6cff30cf739bab9"},{"fixed":"127033b79383a3e78361d7e971588aa8849f5124"},{"fixed":"e65848e4ce352bac9e3465099354c8b8f845391f"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74472.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.0.0"},{"fixed":"6.6.151"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.103"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.44"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74472.json"}}],"schema_version":"1.9.0"}