Re: [PATCH 05/10] fuzz/virtio-scsi: remove fork-based fuzzer

From: Darren Kenny <darren.kenny@oracle.com>
To: Alexander Bulekov <alxndr@bu.edu>, qemu-devel@nongnu.org
Cc: Alexander Bulekov <alxndr@bu.edu>,
	Stefan Hajnoczi <stefanha@redhat.com>,
	Bandan Das <bsd@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>,
	Thomas Huth <thuth@redhat.com>, Qiuhao Li <Qiuhao.Li@outlook.com>,
	Laurent Vivier <lvivier@redhat.com>
Subject: Re: [PATCH 05/10] fuzz/virtio-scsi: remove fork-based fuzzer
Date: Mon, 13 Feb 2023 14:42:15 +0000	[thread overview]
Message-ID: <m2ilg5r5iw.fsf@oracle.com> (raw)
In-Reply-To: <20230205042951.3570008-6-alxndr@bu.edu>

On Saturday, 2023-02-04 at 23:29:46 -05, Alexander Bulekov wrote:
> Signed-off-by: Alexander Bulekov <alxndr@bu.edu>

Reviewed-by: Darren Kenny <darren.kenny@oracle.com>

Thanks,

Darren.

> ---
>  tests/qtest/fuzz/virtio_scsi_fuzz.c | 51 ++++-------------------------
>  1 file changed, 7 insertions(+), 44 deletions(-)
>
> diff --git a/tests/qtest/fuzz/virtio_scsi_fuzz.c b/tests/qtest/fuzz/virtio_scsi_fuzz.c
> index b3220ef6cb..8b26e951ae 100644
> --- a/tests/qtest/fuzz/virtio_scsi_fuzz.c
> +++ b/tests/qtest/fuzz/virtio_scsi_fuzz.c
> @@ -20,7 +20,6 @@
>  #include "standard-headers/linux/virtio_pci.h"
>  #include "standard-headers/linux/virtio_scsi.h"
>  #include "fuzz.h"
> -#include "fork_fuzz.h"
>  #include "qos_fuzz.h"
>  
>  #define PCI_SLOT                0x02
> @@ -132,48 +131,24 @@ static void virtio_scsi_fuzz(QTestState *s, QVirtioSCSIQueues* queues,
>      }
>  }
>  
> -static void virtio_scsi_fork_fuzz(QTestState *s,
> -        const unsigned char *Data, size_t Size)
> -{
> -    QVirtioSCSI *scsi = fuzz_qos_obj;
> -    static QVirtioSCSIQueues *queues;
> -    if (!queues) {
> -        queues = qvirtio_scsi_init(scsi->vdev, 0);
> -    }
> -    if (fork() == 0) {
> -        virtio_scsi_fuzz(s, queues, Data, Size);
> -        flush_events(s);
> -        _Exit(0);
> -    } else {
> -        flush_events(s);
> -        wait(NULL);
> -    }
> -}
> -
>  static void virtio_scsi_with_flag_fuzz(QTestState *s,
>          const unsigned char *Data, size_t Size)
>  {
>      QVirtioSCSI *scsi = fuzz_qos_obj;
>      static QVirtioSCSIQueues *queues;
>  
> -    if (fork() == 0) {
> -        if (Size >= sizeof(uint64_t)) {
> -            queues = qvirtio_scsi_init(scsi->vdev, *(uint64_t *)Data);
> -            virtio_scsi_fuzz(s, queues,
> -                             Data + sizeof(uint64_t), Size - sizeof(uint64_t));
> -            flush_events(s);
> -        }
> -        _Exit(0);
> -    } else {
> +    if (Size >= sizeof(uint64_t)) {
> +        queues = qvirtio_scsi_init(scsi->vdev, *(uint64_t *)Data);
> +        virtio_scsi_fuzz(s, queues,
> +                Data + sizeof(uint64_t), Size - sizeof(uint64_t));
>          flush_events(s);
> -        wait(NULL);
>      }
> +    fuzz_reboot(s);
>  }
>  
>  static void virtio_scsi_pre_fuzz(QTestState *s)
>  {
>      qos_init_path(s);
> -    counter_shm_init();
>  }
>  
>  static void *virtio_scsi_test_setup(GString *cmd_line, void *arg)
> @@ -189,22 +164,10 @@ static void *virtio_scsi_test_setup(GString *cmd_line, void *arg)
>  
>  static void register_virtio_scsi_fuzz_targets(void)
>  {
> -    fuzz_add_qos_target(&(FuzzTarget){
> -                .name = "virtio-scsi-fuzz",
> -                .description = "Fuzz the virtio-scsi virtual queues, forking "
> -                                "for each fuzz run",
> -                .pre_vm_init = &counter_shm_init,
> -                .pre_fuzz = &virtio_scsi_pre_fuzz,
> -                .fuzz = virtio_scsi_fork_fuzz,},
> -                "virtio-scsi",
> -                &(QOSGraphTestOptions){.before = virtio_scsi_test_setup}
> -                );
> -
>      fuzz_add_qos_target(&(FuzzTarget){
>                  .name = "virtio-scsi-flags-fuzz",
> -                .description = "Fuzz the virtio-scsi virtual queues, forking "
> -                "for each fuzz run (also fuzzes the virtio flags)",
> -                .pre_vm_init = &counter_shm_init,
> +                .description = "Fuzz the virtio-scsi virtual queues. "
> +                "Also fuzzes the virtio flags",
>                  .pre_fuzz = &virtio_scsi_pre_fuzz,
>                  .fuzz = virtio_scsi_with_flag_fuzz,},
>                  "virtio-scsi",
> -- 
> 2.39.0