History

Changpeng Liu a02483e67c module/bdev_virtio_scsi: use the correct `num_queues` value Parameter `num_queues` for virtio_scsi PCI device means maximum number of queues, it SHOULD include the `eventq` and `controlq`, while for `vhost_user` RPC call, it means the number of IO queues, so here we use it as `max_queues` in lib/virtio and add the fixed number queues for `vhost_user` SCSI device. Also fix `vhost_fuzz` to get `num_queues` earlier than negotiate the feature bits. Change-Id: I41b3da5e4b4dc37127befd414226ea6eafcd9ad0 Signed-off-by: Changpeng Liu <changpeng.liu@intel.com> Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/13791 Tested-by: SPDK CI Jenkins <sys_sgci@intel.com> Reviewed-by: Jim Harris <james.r.harris@intel.com> Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>		2022-08-04 11:24:40 +00:00
..
.gitignore	test: add a fuzzer for the vhost API	2019-07-08 09:18:19 +00:00
example.json	test: add a fuzzer for the vhost API	2019-07-08 09:18:19 +00:00
Makefile	Replace most BSD 3-clause license text with SPDX identifier.	2022-06-09 07:35:12 +00:00
README.md	markdownlint: enable rule MD040	2021-09-08 21:53:48 +00:00
vhost_fuzz_rpc.c	Replace most BSD 3-clause license text with SPDX identifier.	2022-06-09 07:35:12 +00:00
vhost_fuzz.c	module/bdev_virtio_scsi: use the correct `num_queues` value	2022-08-04 11:24:40 +00:00
vhost_fuzz.h	Replace most BSD 3-clause license text with SPDX identifier.	2022-06-09 07:35:12 +00:00

README.md

Overview

This application is intended to fuzz test the SPDK vhost target by supplying malformed or invalid requests across a unix domain socket. This fuzzer currently supports fuzzing both vhost block and vhost scsi devices. When fuzzing a vhost scsi device, users can select whether to fuzz the scsi I/O queue or the scsi admin queue. Please see the NVMe fuzzer readme for information on how output is generated, debugging procedures, and the JSON format expected when supplying preconstructed values to the fuzzer.

Request Types

Like the NVMe fuzzer, there is an example json file showing the types of requests that the application accepts. Since the vhost application accepts both vhost block and vhost scsi commands, there are three distinct object types that can be passed in to the application.

vhost_blk_cmd
vhost_scsi_cmd
vhost_scsi_mgmt_cmd

Each one of these objects contains distinct data types and they should not be used interchangeably.

All three of the data types begin with three iovec structures describing the request, data, and response memory locations. By default, these values are overwritten by the application even when supplied as part of a json file. This is because the request and resp data pointers are intended to point to portions of the data structure.

If you want to override these iovec values using a json file, you can specify the -k option. In most cases, this will just result in the application failing all I/O immediately since the request will no longer point to a valid memory location.

It is possible to supply all three types of requests in a single array to the application. They will be parsed and submitted to the proper block devices.

RPC

The vhost fuzzer differs from the NVMe fuzzer in that it expects devices to be configured via rpc. The fuzzer should always be started with the --wait-for-rpc argument. Please see below for an example of starting the fuzzer.

./test/app/fuzz/vhost_fuzz/vhost_fuzz -t 30 --wait-for-rpc &
./scripts/rpc.py fuzz_vhost_create_dev -s ./Vhost.1 -b -V
./scripts/rpc.py fuzz_vhost_create_dev -s ./naa.VhostScsi0.1 -l -V
./scripts/rpc.py framework_start_init