1a3f540d63
After nvmet_install_queue() sets sq->ctrl calling to nvmet_sq_destroy()
reduces the controller refcount. In case nvmet_install_queue() fails,
calling to nvmet_ctrl_put() is done twice (at nvmet_sq_destroy and
nvmet_execute_io_connect/nvmet_execute_admin_connect) instead of once for
the queue which leads to use after free of the controller. Fix this by set
NULL at sq->ctrl in case of a failure at nvmet_install_queue().
The bug leads to the following Call Trace:
[65857.994862] refcount_t: underflow; use-after-free.
[65858.108304] Workqueue: events nvmet_rdma_release_queue_work [nvmet_rdma]
[65858.115557] RIP: 0010:refcount_warn_saturate+0xe5/0xf0
[65858.208141] Call Trace:
[65858.211203] nvmet_sq_destroy+0xe1/0xf0 [nvmet]
[65858.216383] nvmet_rdma_release_queue_work+0x37/0xf0 [nvmet_rdma]
[65858.223117] process_one_work+0x167/0x370
[65858.227776] worker_thread+0x49/0x3e0
[65858.232089] kthread+0xf5/0x130
[65858.235895] ? max_active_store+0x80/0x80
[65858.240504] ? kthread_bind+0x10/0x10
[65858.244832] ret_from_fork+0x1f/0x30
[65858.249074] ---[ end trace f82d59250b54beb7 ]---
Fixes: bb1cc74790eb ("nvmet: implement valid sqhd values in completions")
Fixes: 1672ddb8d691 ("nvmet: Add install_queue callout")
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.