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CVE PROGRAM SOURCE RECORD8.8 High

CVE-2026-72469

xprtrdma: Fix ep kref imbalance on ADDR_CHANGE

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Status
Published
Published
Updated
Assigning organization
Linux

Description

In the Linux kernel, the following vulnerability has been resolved: xprtrdma: Fix ep kref imbalance on ADDR_CHANGE rpcrdma_cm_event_handler() falls through to the disconnected: label on RDMA_CM_EVENT_ADDR_CHANGE and calls rpcrdma_ep_put() with no matching get when the event arrives before RDMA_CM_EVENT_ESTABLISHED. The kref then underflows during connect teardown and rpcrdma_xprt_disconnect() operates on a freed ep. Reference counts across a normal connection lifecycle: rpcrdma_ep_create() kref_init ->1 rpcrdma_xprt_connect() ep_get ->2 (before post_recvs) RDMA_CM_EVENT_ESTABLISHED ep_get ->3 RDMA_CM_EVENT_DISCONNECTED ep_put ->2 rpcrdma_xprt_drain() ep_put ->1 rpcrdma_xprt_disconnect() tail ep_put ->0 (ep_destroy) The connect-time get in rpcrdma_xprt_connect(), taken just before rpcrdma_post_recvs() "while there are outstanding Receives," is balanced by rpcrdma_xprt_drain. ADDR_CHANGE before ESTABLISHED has no get to consume, so its put drops the count to 1 and the drain put then frees the ep while rpcrdma_xprt_disconnect() still holds a pointer to it. Fix by dispatching on the prior re_connect_status via xchg(): for prev == 0 (pre-ESTABLISHED) wake the connect waiter and return with no put; for prev == 1 call rpcrdma_force_disconnect() and return. The case-1 arm relies on the subsequent RDMA_CM_EVENT_DISCONNECTED event -- reliably delivered when rdma_disconnect() is called on a still-connected cm_id -- to balance the ESTABLISHED get; rpcrdma_xprt_drain() continues to balance only that connect-time get. Any other prior value means teardown is already in flight.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • 2acc5cae292355f5f18ad377a2a966e7f03c8fec to < a562485c359d0b20a99d466b042af9c2f7ff3326affected
  • 2acc5cae292355f5f18ad377a2a966e7f03c8fec to < cfd1bab66b042da7a778786685125656c695931baffected
  • 2acc5cae292355f5f18ad377a2a966e7f03c8fec to < d0479c2b12974aa188b10d221a5770126b118b6daffected
  • 2acc5cae292355f5f18ad377a2a966e7f03c8fec to < ffc07790539736a5d029f6a3c966b46c529f93a8affected
  • 2acc5cae292355f5f18ad377a2a966e7f03c8fec to < af9b65b29af341932625c4283dc7a23cdb62688aaffected
  • 2fcbf07a4f23174a45e015b62a8e42ddbc2e53efaffected
  • 5.7.9 to < 5.8affected

Linux Linux

Default version status: affected

  • 5.8affected
  • 0 to < 5.8unaffected
  • 6.6.160 to ≤ 6.6.*unaffected
  • 6.12.97 to ≤ 6.12.*unaffected
  • 6.18.40 to ≤ 6.18.*unaffected
  • 7.1.5 to ≤ 7.1.*unaffected
  • 7.2 to ≤ *unaffected

References