Re: [syzbot] WARNING in iomap_iter

From: Siddh Raman Pant
Date: Mon Aug 22 2022 - 10:50:47 EST


On Mon, 22 Aug 2022 20:15:28 +0530 Matthew Wilcox wrote:
> On Sun, Aug 21, 2022 at 05:18:16PM +0530, Siddh Raman Pant wrote:
> > @@ -979,9 +979,15 @@ loop_set_status_from_info(struct loop_device *lo,
> >
> > lo->lo_offset = info->lo_offset;
> > lo->lo_sizelimit = info->lo_sizelimit;
> > + lo->lo_flags = info->lo_flags;
> > +
> > + /* loff_t/int vars are assigned __u64/__u32 vars (respectively) */
> > + if (lo->lo_offset < 0 || lo->lo_sizelimit < 0 || lo->lo_flags < 0)
> > + return -EOVERFLOW;
>
> Why would you check lo_flags? That really, really should be an unsigned
> type.

I agree, but the loop_device struct has (see line 54 of loop.c):
int lo_flags;

Thus, I checked for it, as we are not changing any types.

Thanks,
Siddh