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Date:   Mon, 22 Aug 2022 20:19:43 +0530
From:   Siddh Raman Pant <code@siddh.me>
To:     "Matthew Wilcox" <willy@infradead.org>
Cc:     "david" <david@fromorbit.com>, "djwong" <djwong@kernel.org>,
        "fgheet255t" <fgheet255t@gmail.com>, "hch" <hch@infradead.org>,
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        "linux-fsdevel" <linux-fsdevel@vger.kernel.org>,
        "linux-kernel" <linux-kernel@vger.kernel.org>,
        "linux-xfs" <linux-xfs@vger.kernel.org>,
        "riteshh" <riteshh@linux.ibm.com>,
        "syzbot+a8e049cd3abd342936b6" 
        <syzbot+a8e049cd3abd342936b6@syzkaller.appspotmail.com>,
        "syzkaller-bugs" <syzkaller-bugs@googlegroups.com>
Message-ID: <182c607e79a.820e4a7012709.6365464609772129416@siddh.me>
In-Reply-To: <YwOWiDKhVxm7m0fa@casper.infradead.org>
References: <182c028abf0.2dc6f7c973088.2963173753499991828@siddh.me>
 <20220821114816.24193-1-code@siddh.me> <YwOWiDKhVxm7m0fa@casper.infradead.org>
Subject: Re: [syzbot] WARNING in iomap_iter
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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