{"id":"CVE-2026-89974","summary":"nvme-fc: fix double free of fabrics options when nvme_add_ctrl() fails","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnvme-fc: fix double free of fabrics options when nvme_add_ctrl() fails\n\nnvmf_create_ctrl() owns the fabrics options and frees them whenever\n-\u003ecreate_ctrl() returns an error, so a transport must not free them on\nits own error paths.  nvme-fc tracks this by testing ctrl-\u003ectrl.opts in\nnvme_fc_ctrl_free(), which requires nvme_fc_init_ctrl() to clear that\npointer on every error exit.\n\nThe coupling is implicit, and commit 1a9e218195a5 (\"nvme: split device\nadd from initialization\") broke it by adding a second error exit.  When\nnvme_add_ctrl() fails, nvme_fc_init_ctrl() jumps to out_put_ctrl:, past\nthe \"ctrl-\u003ectrl.opts = NULL\" that only sits on the fail_ctrl: path, so\nnvme_fc_ctrl_free() frees the options and nvmf_create_ctrl() frees them\na second time:\n\n  BUG: KASAN: slab-use-after-free in nvmf_free_options+0x30/0x190\n   nvmf_free_options+0x30/0x190 drivers/nvme/host/fabrics.c:1284\n   nvmf_create_ctrl drivers/nvme/host/fabrics.c:1374 [inline]\n  Freed by task 5534:\n   nvme_fc_ctrl_free drivers/nvme/host/fc.c:2374 [inline]\n   nvme_fc_init_ctrl+0xe17/0x1450 drivers/nvme/host/fc.c:3605\n\nnvme_add_ctrl() fails when dev_set_name() cannot allocate, so this is\nreachable under memory pressure or fault injection.  Without KASAN the\noptions are freed twice.\n\nRather than clear the pointer on the second exit as well, derive\nownership the way nvme-tcp, nvme-rdma and nvme-loop do, from list\nmembership: their free_ctrl leaves the options alone unless the\ncontroller made it onto the transport list.\n\nThe list cannot simply be populated on the success path as it is there.\nnvme-fc runs the initial connect synchronously via flush_delayed_work(),\nand the controller has to be reachable on rport-\u003ectrl_list for the whole\nof it: nvme_fc_unregister_remoteport() needs to find it to signal\nconnectivity loss, nvme_fc_match_disconn_ls() matches an incoming\nDisconnect Association LS against ctrl-\u003eassociation_id, which is only\nassigned during that window, nvme_fc_resume_controller() needs it on\nremoteport re-registration, and nvme_fc_existing_controller() uses it to\nreject a duplicate connect racing the one in flight.\n\nKeep the insertion where it is and add a fail_unlist: label, falling\ninto fail_ctrl:, for the error paths that run after it.  The earlier\nerror paths never reach the insertion and keep using fail_ctrl:\ndirectly, so the list is only touched where the controller is actually\non it.\n\nnvme_fc_ctrl_free() cannot use the plain \"goto free_ctrl\" the other\ntransports use, because it still has to put_device(), release the rport\nreference and free the ida entry for resources taken before the\ninsertion.  Sample list_empty() under rport-\u003elock instead.\n\nctrl-\u003ectrl.opts also stays valid for the whole teardown now.  That is\nnot the bug being fixed, but it removes some fragility around the old\nidiom: nvme_free_ctrl() calls nvme_auth_free() before -\u003efree_ctrl(), and\nctrl_max_dhchaps() dereferences ctrl-\u003eopts without a NULL check when\nctrl-\u003edhchap_ctxs is set, which nvme-fc permits since NVMF_ALLOWED_OPTS\nallows the dhchap options.  The nvme sysfs attributes that dereference\nctrl-\u003eopts, such as hostnqn and address, evaluate their is_visible()\ntest once at device_add() time and stay readable until\ncdev_device_del().","modified":"2026-09-18T03:46:40.754247530Z","published":"2026-09-16T10:32:53.124Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89974.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/56e6279266f6962bb2d38a54397e3c605165b0c5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5f89d68c00ccd1b25151da0bf660012380c2bad9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7df913a7ced5d7349f0b23bdcf25ad54fe83a1c1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8bd14aa065112b4d523bea690027c7527a6224f6"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89974.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89974"},{"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":"1a9e218195a55d0a31e8cbe263aa2f618580ef1d"},{"fixed":"8bd14aa065112b4d523bea690027c7527a6224f6"},{"fixed":"7df913a7ced5d7349f0b23bdcf25ad54fe83a1c1"},{"fixed":"5f89d68c00ccd1b25151da0bf660012380c2bad9"},{"fixed":"56e6279266f6962bb2d38a54397e3c605165b0c5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89974.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.11.0"},{"fixed":"6.12.110"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.51"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89974.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}