Re: [PATCH 0/2] Fix pointer arithmetic in indirect read for libvhost-user and libvduse

[Daniel P . Berrangé]

Adding Michael back to the CC, since he's the designated
maintainer for libvhost-user/

Michael, could you give these patches a review since
they've been pending for many months now.

On Sun, Feb 04, 2024 at 12:41:31PM +0300, Тимур wrote:
> Hello, I am very sorry for bothering community on a such minor problem
> again, but I got no response for a few weeks, so maybe I have started
> thread on a wrong mailing list, so I made an issue in gitlab issue tracker:
> https://gitlab.com/qemu-project/qemu/-/issues/2149 referencing this thread.
> 
> Maybe, it would help attract proper eyes to such a simple problem, so no
> one bothers in trying to fix it, albeit it lives in the codebase for some
> time already and is being copied around.
> 
> Sincerely,
> Temir.
> 
> сб, 13 янв. 2024 г. в 04:28, Temir Zharaspayev <masscry@gmail.com>:
> 
> > Hello! I have found a problem with virtqueue_read_indirect_desc function,
> > which
> > was advancing pointer to struct as it was a byte pointer, so every element
> > comming after first chunk would be copied somewhere out of buffer.
> >
> > As I understand this is cold path, but nevertheless worth fixing.
> >
> > Also, exacly same problem in vduse_queue_read_indirect_desc function,
> > because
> > as I understand it is a copy of virtqueue_read_indirect_desc with vduse
> > backend.
> >
> > I was not sure if element of scattered buffer may end in the middle of
> > vring_desc struct data, so instead of writing
> > desc += read_len/sizeof(struct vring_desc)
> > have implemented fix with proper byte pointer arithmetic.
> >
> > Sincerely,
> > Temir.
> >
> > Temir Zharaspayev (2):
> >   libvhost-user: Fix pointer arithmetic in indirect read
> >   libvduse: Fix pointer arithmetic in indirect read
> >
> >  subprojects/libvduse/libvduse.c           | 11 ++++++-----
> >  subprojects/libvhost-user/libvhost-user.c | 11 ++++++-----
> >  2 files changed, 12 insertions(+), 10 deletions(-)
> >
> > --
> > 2.34.1
> >
> >

With regards,
Daniel
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