Re: [Qemu-devel] [PATCH] mmap: add check if requested memory area fits target address space

[andrzej zaborowski]

On 17/10/2008, Kirill A. Shutemov <address@hidden> wrote:
> Signed-off-by: Kirill A. Shutemov <address@hidden>
>  ---
>   linux-user/mmap.c |    5 +++++
>   1 files changed, 5 insertions(+), 0 deletions(-)
>
>  diff --git a/linux-user/mmap.c b/linux-user/mmap.c
>  index bc20f4b..9a2f355 100644
>  --- a/linux-user/mmap.c
>  +++ b/linux-user/mmap.c
>  @@ -388,6 +388,11 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, 
> int prot,
>          end = start + len;
>          real_end = HOST_PAGE_ALIGN(end);
>
>  +        if ((unsigned long)start + len > (abi_ulong) -1) {
>  +            errno = EINVAL;
>  +            goto fail;
>  +        }

I'm being picky but this would prevent the last byte from being used?
:p  (or the last page because len is aligned?)

I'm not sure unsigned long is the best choice.

Cheers