[PATCH] nvmet: pci-epf: put CQ ref on create_cq mapping failure

[Keith Busch]

On Tue, Aug 04, 2026 at 09:36:25PM +0000, Yifei Gao wrote:
> nvmet_pci_epf_create_cq() calls nvmet_cq_create(), which takes a
> reference on the controller and installs the completion queue. If the
> subsequent PCI address-space mapping fails or returns a too-small partial
> mapping, the function jumps to err_internal / err_unmap_queue without
> calling nvmet_cq_put(). The matching put in nvmet_pci_epf_delete_cq() is
> gated on NVMET_PCI_EPF_Q_LIVE, which is only set after the mapping
> succeeds, so teardown never releases these references. A remote PCI host
> that drives Create IO CQ commands with a failing PRP1/pci_addr therefore
> leaks the CQ and a controller reference on each attempt.
> 
> Drop the CQ reference on the mapping-failure paths. The err_internal and
> err_unmap_queue labels are only reachable after nvmet_cq_create() has
> succeeded, so this pairs the create/put correctly.

Thanks, applied to nvme-7.3.