{"id":"CVE-2026-74472","state":"PUBLISHED","title":"ublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()","description":"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->dev_info and then fixes up the fields the driver owns, but misses\n->state and ->ublksrv_pid.\n\nA device added with ->state = UBLK_S_DEV_LIVE passes the\n\"->state != UBLK_S_DEV_DEAD\" test that ublk_stop_dev_unlocked() uses as its\nproxy for \"a disk is attached\", while ->ub_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 ->state 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 ->ublksrv_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 ->state 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->state.  The oops became reachable once the disk allocation moved to\nSTART_DEV and those checks switched to ->state.","publishedAt":"2026-08-15T12:27:08.759Z","updatedAt":"2026-08-19T16:37:23.182Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"787c944502e7e63d20a9201bada77e0dd924f458","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"ee41b00858ca65b4428e99efe39a4277c1f043d2","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"b67ce16b26ad0f14cfd6071013840aa95f823bea","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"205feb72e5beb3140e4e1403b6cff30cf739bab9","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"127033b79383a3e78361d7e971588aa8849f5124","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"e65848e4ce352bac9e3465099354c8b8f845391f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/block/ublk_drv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.0","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.151","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.103","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.44","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.8","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/block/ublk_drv.c"]}],"references":["https://git.kernel.org/stable/c/787c944502e7e63d20a9201bada77e0dd924f458","https://git.kernel.org/stable/c/ee41b00858ca65b4428e99efe39a4277c1f043d2","https://git.kernel.org/stable/c/b67ce16b26ad0f14cfd6071013840aa95f823bea","https://git.kernel.org/stable/c/205feb72e5beb3140e4e1403b6cff30cf739bab9","https://git.kernel.org/stable/c/127033b79383a3e78361d7e971588aa8849f5124","https://git.kernel.org/stable/c/e65848e4ce352bac9e3465099354c8b8f845391f"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74472.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74472","state":"PUBLISHED","datePublished":"2026-08-15T12:27:08.759Z","dateUpdated":"2026-08-19T16:37:23.182Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.902Z"},"containers":{"cna":{"title":"ublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()","descriptions":[{"lang":"en","value":"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->dev_info and then fixes up the fields the driver owns, but misses\n->state and ->ublksrv_pid.\n\nA device added with ->state = UBLK_S_DEV_LIVE passes the\n\"->state != UBLK_S_DEV_DEAD\" test that ublk_stop_dev_unlocked() uses as its\nproxy for \"a disk is attached\", while ->ub_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 ->state 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 ->ublksrv_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 ->state 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->state.  The oops became reachable once the disk allocation moved to\nSTART_DEV and those checks switched to ->state."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"787c944502e7e63d20a9201bada77e0dd924f458","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"ee41b00858ca65b4428e99efe39a4277c1f043d2","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"b67ce16b26ad0f14cfd6071013840aa95f823bea","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"205feb72e5beb3140e4e1403b6cff30cf739bab9","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"127033b79383a3e78361d7e971588aa8849f5124","versionType":"git"},{"version":"6d9e6dfdf3b207701471f364121c67eefb000682","status":"affected","lessThan":"e65848e4ce352bac9e3465099354c8b8f845391f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/block/ublk_drv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.0","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.151","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.103","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.44","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.8","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/block/ublk_drv.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/787c944502e7e63d20a9201bada77e0dd924f458"},{"url":"https://git.kernel.org/stable/c/ee41b00858ca65b4428e99efe39a4277c1f043d2"},{"url":"https://git.kernel.org/stable/c/b67ce16b26ad0f14cfd6071013840aa95f823bea"},{"url":"https://git.kernel.org/stable/c/205feb72e5beb3140e4e1403b6cff30cf739bab9"},{"url":"https://git.kernel.org/stable/c/127033b79383a3e78361d7e971588aa8849f5124"},{"url":"https://git.kernel.org/stable/c/e65848e4ce352bac9e3465099354c8b8f845391f"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-19T16:37:23.182Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.1.183"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.6.151"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.12.103"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.18.44"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"7.1.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}