Re: [PATCH v1 2/2] async_tx: fix possible negative array indexing

[Dan Williams]

On Mon, Mar 16, 2020 at 11:16 PM Rayagonda Kokatanur
<rayagonda.kokatanur@xxxxxxxxxxxx> wrote:
>
> Fix possible negative array index read in __2data_recov_5() function.
>
> Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@xxxxxxxxxxxx>
> ---
>  crypto/async_tx/async_raid6_recov.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/crypto/async_tx/async_raid6_recov.c b/crypto/async_tx/async_raid6_recov.c
> index 33f2a8f8c9f4..9cd016cb2d09 100644
> --- a/crypto/async_tx/async_raid6_recov.c
> +++ b/crypto/async_tx/async_raid6_recov.c
> @@ -206,7 +206,7 @@ __2data_recov_5(int disks, size_t bytes, int faila, int failb,
>                 good_srcs++;
>         }
>
> -       if (good_srcs > 1)
> +       if ((good_srcs > 1) || (good < 0))
>                 return NULL;

Read the code again, I don't see how this can happen.