Re: [PATCH for-9.1] linux-user: Handle short reads in mmap_h_gt_g

[Richard Henderson]

On 8/16/24 15:57, Philippe Mathieu-Daudé wrote:
> On 15/8/24 23:32, Richard Henderson wrote:
> > In particular, if an image has a large bss, we can hit
> > EOF before reading all host_len bytes of the mapping.
> >
> > Cc: qemu-stable@nongnu.org
> > Fixes: eb5027ac618 ("linux-user: Split out mmap_h_gt_g")
> > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2504
> > Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> > ---
> >   linux-user/mmap.c | 19 +++++++++++++++----
> >   1 file changed, 15 insertions(+), 4 deletions(-)
> >
> > diff --git a/linux-user/mmap.c b/linux-user/mmap.c
> > index 6418e811f6..de9ab13754 100644
> > --- a/linux-user/mmap.c
> > +++ b/linux-user/mmap.c
> > @@ -853,10 +853,21 @@ static abi_long mmap_h_gt_g(abi_ulong start, abi_ulong 
> > len,
> >       }
> >       if (misaligned_offset) {
> > -        /* TODO: The read could be short. */
>
> I note there are other short reads in {linux,bsd}-user/mmap.c.

Ah, via mmap_frag.  Hmm, yes.  Worth fixing at the same time.


r~