linux/drivers/nvme
Sagi Grimberg 73964c1d07 nvmet-rdma: fix possible bad dereference when freeing rsps
It is possible that the host connected and saw a cm established
event and started sending nvme capsules on the qp, however the
ctrl did not yet see an established event. This is why the
rsp_wait_list exists (for async handling of these cmds, we move
them to a pending list).

Furthermore, it is possible that the ctrl cm times out, resulting
in a connect-error cm event. in this case we hit a bad deref [1]
because in nvmet_rdma_free_rsps we assume that all the responses
are in the free list.

We are freeing the cmds array anyways, so don't even bother to
remove the rsp from the free_list. It is also guaranteed that we
are not racing anything when we are releasing the queue so no
other context accessing this array should be running.

[1]:
--
Workqueue: nvmet-free-wq nvmet_rdma_free_queue_work [nvmet_rdma]
[...]
pc : nvmet_rdma_free_rsps+0x78/0xb8 [nvmet_rdma]
lr : nvmet_rdma_free_queue_work+0x88/0x120 [nvmet_rdma]
 Call trace:
 nvmet_rdma_free_rsps+0x78/0xb8 [nvmet_rdma]
 nvmet_rdma_free_queue_work+0x88/0x120 [nvmet_rdma]
 process_one_work+0x1ec/0x4a0
 worker_thread+0x48/0x490
 kthread+0x158/0x160
 ret_from_fork+0x10/0x18
--

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2024-05-08 06:17:01 -07:00
..
common nvme-common: add module description 2024-01-31 16:03:49 -08:00
host nvme-pci: Add quirk for broken MSIs 2024-05-07 07:55:14 -07:00
target nvmet-rdma: fix possible bad dereference when freeing rsps 2024-05-08 06:17:01 -07:00
Kconfig nvme: implement In-Band authentication 2022-08-02 17:14:49 -06:00
Makefile nvme: common: make keyring and auth separate modules 2023-11-07 10:05:15 -08:00