Re: [Qemu-devel] [PATCH] overflow of int ret: use ssize_t for ret

[Stefan Priebe - Profihost AG]

Hi Andreas,

thanks for your comment. Do i have to resend this patch?

--
Greets,
Stefan

Am 22.11.2012 17:40, schrieb Andreas Färber:
> Am 22.11.2012 10:07, schrieb Stefan Priebe:
> > When acb->cmd is WRITE or DISCARD block/rbd stores rcb->size into acb->ret
> >
> > Look here:
> >     if (acb->cmd == RBD_AIO_WRITE ||
> >          acb->cmd == RBD_AIO_DISCARD) {
> >          if (r<  0) {
> >              acb->ret = r;
> >              acb->error = 1;
> >          } else if (!acb->error) {
> >              acb->ret = rcb->size;
> >          }
> >
> > right now acb->ret is just an int and we might get an overflow if size is too 
> > big.
> > For discards rcb->size holds the size of the discard - this might be some TB if 
> > you
> > discard a whole device.
> >
> > The steps to reproduce are:
> > mkfs.xfs -f a whole device bigger than int in bytes. mkfs.xfs sends a discard. 
> > Important is that you use scsi-hd and set discard_granularity=512. Otherwise 
> > rbd disabled discard support.
>
> Whatever type you decide to use, please add an identifying topic such as
> "block/rbd:" in the subject (int ret is very generic!), and this patch
> is missing a Signed-off-by.
>
> Regards,
> Andreas