GHSA-GHCQ-8J2M-VFJM
Vulnerability from github – Published: 2026-05-27 15:33 – Updated: 2026-05-27 15:33In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Fix race condition in QP timer handlers
I encontered the following warning: WARNING: drivers/infiniband/sw/rxe/rxe_task.c:249 at rxe_sched_task+0x1c8/0x238 [rdma_rxe], CPU#0: swapper/0/0 ... libsha1 [last unloaded: ip6_udp_tunnel] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G C 6.19.0-rc5-64k-v8+ #37 PREEMPT Tainted: [C]=CRAP Hardware name: Raspberry Pi 4 Model B Rev 1.2 Call trace: rxe_sched_task+0x1c8/0x238 [rdma_rxe] (P) retransmit_timer+0x130/0x188 [rdma_rxe] call_timer_fn+0x68/0x4d0 __run_timers+0x630/0x888 ... WARNING: drivers/infiniband/sw/rxe/rxe_task.c:38 at rxe_sched_task+0x1c0/0x238 [rdma_rxe], CPU#0: swapper/0/0 ... WARNING: drivers/infiniband/sw/rxe/rxe_task.c:111 at do_work+0x488/0x5c8 [rdma_rxe], CPU#3: kworker/u17:4/93400 ... refcount_t: underflow; use-after-free. WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x138/0x1a0, CPU#3: kworker/u17:4/93400
The issue is caused by a race condition between retransmit_timer() and rxe_destroy_qp, leading to the Queue Pair's (QP) reference count dropping to zero during timer handler execution.
It seems this warning is harmless because rxe_qp_do_cleanup() will flush all pending timers and requests.
Example of flow causing the issue:
CPU0 CPU1 retransmit_timer() { spin_lock_irqsave rxe_destroy_qp() __rxe_cleanup() __rxe_put() // qp->ref_count decrease to 0 rxe_qp_do_cleanup() { if (qp->valid) { rxe_sched_task() { WARN_ON(rxe_read(task->qp) <= 0); } } spin_unlock_irqrestore } spin_lock_irqsave qp->valid = 0 spin_unlock_irqrestore }
Ensure the QP's reference count is maintained and its validity is checked within the timer callbacks by adding calls to rxe_get(qp) and corresponding rxe_put(qp) after use.
{
"affected": [],
"aliases": [
"CVE-2026-45910"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-05-27T14:17:05Z",
"severity": null
},
"details": "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\u0027s (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-\u003eref_count decrease to 0\n rxe_qp_do_cleanup() {\n if (qp-\u003evalid) {\n rxe_sched_task() {\n WARN_ON(rxe_read(task-\u003eqp) \u003c= 0);\n }\n }\n spin_unlock_irqrestore\n}\n spin_lock_irqsave\n qp-\u003evalid = 0\n spin_unlock_irqrestore\n }\n\nEnsure the QP\u0027s 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.",
"id": "GHSA-ghcq-8j2m-vfjm",
"modified": "2026-05-27T15:33:16Z",
"published": "2026-05-27T15:33:16Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45910"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3c2ae79fb19dfd67341c14f1e78a5f1744eacfe2"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5ae9da022ee3c97e6469eabcddce9271501ddbad"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/756c93d6df7c3bc599f6590b8e5afead6a41de1c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/87bf646921430e303176edc4eb07c30160361b73"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/da379ca16af3722f159860d91a99cb6976a7500f"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
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