{"cve":"CVE-2026-45910","nvd":{"published":"2026-05-27T14:17:05.563","modified":"2026-10-19T20:18:21.320","status":"Undergoing Analysis","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Fix race condition in QP timer handlers\n\nI encontered the following warning:\n WARNING: drivers/infiniband/sw/rxe/rxe_task.c:249 at rxe_sched_task+0x1c8/0x238 [rdma_rxe], CPU#0: swapper/0/0\n...\n  libsha1 [last unloaded: ip6_udp_tunnel]\n CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G         C          6.19.0-rc5-64k-v8+ #37 PREEMPT\n Tainted: [C]=CRAP\n Hardware name: Raspberry Pi 4 Model B Rev 1.2\n Call trace:\n  rxe_sched_task+0x1c8/0x238 [rdma_rxe] (P)\n  retransmit_timer+0x130/0x188 [rdma_rxe]\n  call_timer_fn+0x68/0x4d0\n  __run_timers+0x630/0x888\n...\n WARNING: drivers/infiniband/sw/rxe/rxe_task.c:38 at rxe_sched_task+0x1c0/0x238 [rdma_rxe], CPU#0: swapper/0/0\n...\n WARNING: drivers/infiniband/sw/rxe/rxe_task.c:111 at do_work+0x488/0x5c8 [rdma_rxe], CPU#3: kworker/u17:4/93400\n...\n refcount_t: underflow; use-after-free.\n WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x138/0x1a0, CPU#3: kworker/u17:4/93400\n\nThe issue is caused by a race condition between retransmit_timer() and\nrxe_destroy_qp, leading to the Queue Pair's (QP) reference count dropping\nto zero during timer handler execution.\n\nIt seems this warning is harmless because rxe_qp_do_cleanup() will flush\nall pending timers and requests.\n\nExample of flow causing the issue:\n\nCPU0                                   CPU1\nretransmit_timer() {\n    spin_lock_irqsave\n                           rxe_destroy_qp()\n                            __rxe_cleanup()\n                              __rxe_put() // qp->ref_count decrease to 0\n                            rxe_qp_do_cleanup() {\n    if (qp->valid) {\n        rxe_sched_task() {\n            WARN_ON(rxe_read(task->qp) <= 0);\n        }\n    }\n    spin_unlock_irqrestore\n}\n                              spin_lock_irqsave\n                              qp->valid = 0\n                              spin_unlock_irqrestore\n                            }\n\nEnsure the QP's reference count is maintained and its validity is checked\nwithin the timer callbacks by adding calls to rxe_get(qp) and corresponding\nrxe_put(qp) after use.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-362"],"references":["https://git.kernel.org/stable/c/3c2ae79fb19dfd67341c14f1e78a5f1744eacfe2","https://git.kernel.org/stable/c/5ae9da022ee3c97e6469eabcddce9271501ddbad","https://git.kernel.org/stable/c/756c93d6df7c3bc599f6590b8e5afead6a41de1c","https://git.kernel.org/stable/c/87bf646921430e303176edc4eb07c30160361b73","https://git.kernel.org/stable/c/da379ca16af3722f159860d91a99cb6976a7500f"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2026-45910","score":0.00125,"percentile":0.02212,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}