Re: [Qemu-devel] [PATCH 2/3] fuzz: Add fuzzing functions for entries of refcount table and blocks

[Fam Zheng]

On Mon, 08/11 15:55, Maria Kustova wrote:
> Signed-off-by: Maria Kustova <address@hidden>
> ---
>  tests/image-fuzzer/qcow2/fuzz.py | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/tests/image-fuzzer/qcow2/fuzz.py 
> b/tests/image-fuzzer/qcow2/fuzz.py
> index 57527f9..5852b4d 100644
> --- a/tests/image-fuzzer/qcow2/fuzz.py
> +++ b/tests/image-fuzzer/qcow2/fuzz.py
> @@ -18,8 +18,8 @@
>  
>  import random
>  
> -
>  UINT8 = 0xff
> +UINT16 = 0xffff
>  UINT32 = 0xffffffff
>  UINT64 = 0xffffffffffffffff
>  # Most significant bit orders
> @@ -28,6 +28,8 @@ UINT64_M = 63
>  # Fuzz vectors
>  UINT8_V = [0, 0x10, UINT8/4, UINT8/2 - 1, UINT8/2, UINT8/2 + 1, UINT8 - 1,
>             UINT8]
> +UINT16_V = [0, 0x100, 0x1000, UINT16/4, UINT16/2 - 1, UINT16/2, UINT16/2 + 1,
> +            UINT16 - 1, UINT16]
>  UINT32_V = [0, 0x100, 0x1000, 0x10000, 0x100000, UINT32/4, UINT32/2 - 1,
>              UINT32/2, UINT32/2 + 1, UINT32 - 1, UINT32]
>  UINT64_V = UINT32_V + [0x1000000, 0x10000000, 0x100000000, UINT64/4,

Seeing some pattern in the vectors, but since the types are very few, we can
just construct it like this for now.

> @@ -353,3 +355,15 @@ def l2_entry(current):
>      value = offset + (is_cow << UINT64_M) + \
>              (is_compressed << UINT64_M - 1) + is_zero
>      return value
> +
> +
> +def refcount_table_entry(current):
> +    """Fuzz an entry of the refcount table."""
> +    constraints = UINT64_V
> +    return selector(current, constraints)
> +
> +
> +def refcount_block_entry(current):
> +    """Fuzz an entry of a refcount block."""
> +    constraints = UINT16_V
> +    return selector(current, constraints)
> -- 
> 1.9.3
> 

Reviewed-by: Fam Zheng <address@hidden>