Re: [Qemu-devel] [PATCH] qemu-pr-helper: check the return value of fcntl in do_pr_out

[Stefano Garzarella]

Hi Zhengui,
thanks for this patch!

For the next patches, please add a version tag when resending.
"git format-patch" and "git send-email" both understand the
"-v2" option.

On Wed, Mar 20, 2019 at 10:07:27PM +0800, Zhengui li wrote:
> The function fcntl maybe return -1, which is not a unsigned type.
> Unsigned type or Negative values should not do bitwise operator with
> O_ACCMODE.
> 
> Signed-off-by: Zhengui li <address@hidden>
> ---
>  scsi/qemu-pr-helper.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)

Reviewed-by: Stefano Garzarella <address@hidden>

> 
> diff --git a/scsi/qemu-pr-helper.c b/scsi/qemu-pr-helper.c
> index e7af637..fcbe4d9 100644
> --- a/scsi/qemu-pr-helper.c
> +++ b/scsi/qemu-pr-helper.c
> @@ -551,8 +551,14 @@ static int do_pr_out(int fd, const uint8_t *cdb, uint8_t 
> *sense,
>                       const uint8_t *param, int sz)
>  {
>      int resp_sz;
> +    int flags;
>  
> -    if ((fcntl(fd, F_GETFL) & O_ACCMODE) == O_RDONLY) {
> +    flags = fcntl(fd, F_GETFL);
> +    if (flags < 0) {
> +        return -1;
> +    }
> +
> +    if (((unsigned int) flags & O_ACCMODE) == O_RDONLY) {
>          scsi_build_sense(sense, SENSE_CODE(INVALID_OPCODE));
>          return CHECK_CONDITION;
>      }
> -- 
> 2.7.2.windows.1
> 
> 
>