Re: [PATCH v3 2/9] bsd-user/mmap.c: check pread's return value to fix warnings with _FORTIFY_SOURCE

[Kyle Evans]

On Fri, Oct 8, 2021 at 4:24 PM Warner Losh <imp@bsdimp.com> wrote:
>
> From: Mikaël Urankar <mikael.urankar@gmail.com>
>
> Simmilar to the equivalent linux-user: commit fb7e378cf9c, which added
> checking to pread's return value. Update to current qemu standards with
> {} around the if statement.
>
> Signed-off-by: Mikaël Urankar <mikael.urankar@gmail.com>
> Signed-off-by: Warner Losh <imp@bsdimp.com>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  bsd-user/mmap.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/bsd-user/mmap.c b/bsd-user/mmap.c
> index fc3c1480f5..4f4fa3ab46 100644
> --- a/bsd-user/mmap.c
> +++ b/bsd-user/mmap.c
> @@ -174,7 +174,9 @@ static int mmap_frag(abi_ulong real_start,
>              mprotect(host_start, qemu_host_page_size, prot1 | PROT_WRITE);
>
>          /* read the corresponding file data */
> -        pread(fd, g2h_untagged(start), end - start, offset);
> +        if (pread(fd, g2h_untagged(start), end - start, offset) == -1) {
> +            return -1;
> +        }
>
>          /* put final protection */
>          if (prot_new != (prot1 | PROT_WRITE))
> @@ -593,7 +595,9 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int 
> prot,
>                                    -1, 0);
>              if (retaddr == -1)
>                  goto fail;
> -            pread(fd, g2h_untagged(start), len, offset);
> +            if (pread(fd, g2h_untagged(start), len, offset) == -1) {
> +                goto fail;
> +            }
>              if (!(prot & PROT_WRITE)) {
>                  ret = target_mprotect(start, len, prot);
>                  if (ret != 0) {
> --
> 2.32.0
>

Reviewed-by: Kyle Evans <kevans@FreeBSD.org>