{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-21805","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-12-29T08:45:45.771Z","datePublished":"2025-02-27T20:00:58.290Z","dateUpdated":"2026-08-05T11:54:34.615Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T11:54:34.615Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rtrs: Add missing deinit() call\n\nA warning is triggered when repeatedly connecting and disconnecting the\nrnbd:\n list_add corruption. prev->next should be next (ffff88800b13e480), but was ffff88801ecd1338. (prev=ffff88801ecd1340).\n WARNING: CPU: 1 PID: 36562 at lib/list_debug.c:32 __list_add_valid_or_report+0x7f/0xa0\n Workqueue: ib_cm cm_work_handler [ib_cm]\n RIP: 0010:__list_add_valid_or_report+0x7f/0xa0\n  ? __list_add_valid_or_report+0x7f/0xa0\n  ib_register_event_handler+0x65/0x93 [ib_core]\n  rtrs_srv_ib_dev_init+0x29/0x30 [rtrs_server]\n  rtrs_ib_dev_find_or_add+0x124/0x1d0 [rtrs_core]\n  __alloc_path+0x46c/0x680 [rtrs_server]\n  ? rtrs_rdma_connect+0xa6/0x2d0 [rtrs_server]\n  ? rcu_is_watching+0xd/0x40\n  ? __mutex_lock+0x312/0xcf0\n  ? get_or_create_srv+0xad/0x310 [rtrs_server]\n  ? rtrs_rdma_connect+0xa6/0x2d0 [rtrs_server]\n  rtrs_rdma_connect+0x23c/0x2d0 [rtrs_server]\n  ? __lock_release+0x1b1/0x2d0\n  cma_cm_event_handler+0x4a/0x1a0 [rdma_cm]\n  cma_ib_req_handler+0x3a0/0x7e0 [rdma_cm]\n  cm_process_work+0x28/0x1a0 [ib_cm]\n  ? _raw_spin_unlock_irq+0x2f/0x50\n  cm_req_handler+0x618/0xa60 [ib_cm]\n  cm_work_handler+0x71/0x520 [ib_cm]\n\nCommit 667db86bcbe8 (\"RDMA/rtrs: Register ib event handler\") introduced a\nnew element .deinit but never used it at all. Fix it by invoking the\n`deinit()` to appropriately unregister the IB event handler."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL"},"scenarios":[{"lang":"en","value":"AV:N - The rtrs server listens on IN6ADDR_ANY for RDMA CM connection requests and processes remote peers' connect-request private data in `rtrs_rdma_connect()`, which drives both the allocation and the free of the affected object; over RoCEv2 (UDP) and iWARP (TCP) this is IP-routable rather than fabric-local.\nAC:L - The dangling `ib_event_handler` is left registered on every teardown of the last path — deterministic, with no race to win and no precondition outside the attacker's control, since the attacker drives both the connect (register) and the disconnect (free) sides at will.\nPR:N - RTRS performs no authentication whatsoever; `rtrs_srv_rdma_cm_handler()` hands an unauthenticated CONNECT_REQUEST directly to `rtrs_rdma_connect()`, which validates only a magic constant and version before reaching `rtrs_ib_dev_find_or_add()`.\nUI:N - Exploitation requires only that the attacker open and tear down RDMA connections to the listening server; no action by any local user or administrator is involved.\nS:U - The corruption and its consequences are confined to the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The freed `rtrs_ib_dev` remains linked in the IB core's device-wide handler list, so list traversal and the `handler->handler()` dispatch dereference attacker-groomable freed heap memory in the generic kmalloc-96 cache, yielding read and control primitives suitable for disclosing arbitrary kernel memory.\nI:H - `ib_register_event_handler()`'s `list_add_tail()` and any peer handler's `list_del()` write through pointers in the freed object, and `ib_dispatch_event_clients()` calls a function pointer read from it — giving both a write primitive and a direct control-flow hijack after heap spraying.\nA:H - The immediate observed effect is list corruption (WARNING with CONFIG_DEBUG_LIST, silent corruption and subsequent oops/panic without it), and any dispatched IB async event calls into freed memory, crashing the kernel."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/ulp/rtrs/rtrs.c"],"versions":[{"version":"667db86bcbe82e789d82c2e8c8c40756ec2e1999","lessThan":"5a79cc9bc961fafe90787f86e8f53ba6fad8d63b","status":"affected","versionType":"git"},{"version":"667db86bcbe82e789d82c2e8c8c40756ec2e1999","lessThan":"1af2c769032b6b334cd2a867d7d8c7cbbc527b2d","status":"affected","versionType":"git"},{"version":"667db86bcbe82e789d82c2e8c8c40756ec2e1999","lessThan":"81468c4058a62e84e475433b83b3edc613294f5e","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/ulp/rtrs/rtrs.c"],"versions":[{"version":"6.12","status":"affected"},{"version":"0","lessThan":"6.12","status":"unaffected","versionType":"semver"},{"version":"6.12.13","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.13.2","lessThanOrEqual":"6.13.*","status":"unaffected","versionType":"semver"},{"version":"6.14","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.12.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.13.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.14"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/5a79cc9bc961fafe90787f86e8f53ba6fad8d63b"},{"url":"https://git.kernel.org/stable/c/1af2c769032b6b334cd2a867d7d8c7cbbc527b2d"},{"url":"https://git.kernel.org/stable/c/81468c4058a62e84e475433b83b3edc613294f5e"}],"title":"RDMA/rtrs: Add missing deinit() call","x_generator":{"engine":"bippy-1.2.0"}}}}