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Date:   Fri, 21 Sep 2018 17:19:35 -0700
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Subject: Re: [PATCH 3.16 20/63] scsi: sg: allocate with __GFP_ZERO in sg_build_indirect()
From:   syzbot <syzbot+7d26fc1eea198488deab@syzkaller.appspotmail.com>
To:     Ben Hutchings <ben@decadent.org.uk>
Cc:     akpm@linux-foundation.org, ben@decadent.org.uk,
        dgilbert@interlog.com, glider@google.com, jthumshirn@suse.de,
        linux-kernel@vger.kernel.org, martin.petersen@oracle.com,
        stable@vger.kernel.org
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> 3.16.58-rc1 review patch.  If anyone has any objections, please let me  
> know.

> ------------------

> From: Alexander Potapenko <glider@google.com>

> commit a45b599ad808c3c982fdcdc12b0b8611c2f92824 upstream.

> This shall help avoid copying uninitialized memory to the userspace when
> calling ioctl(fd, SG_IO) with an empty command.

> Reported-by: syzbot+7d26fc1eea198488deab@syzkaller.appspotmail.com
> Signed-off-by: Alexander Potapenko <glider@google.com>
> Acked-by: Douglas Gilbert <dgilbert@interlog.com>
> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
> ---
>   drivers/scsi/sg.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)

> --- a/drivers/scsi/sg.c
> +++ b/drivers/scsi/sg.c
> @@ -1825,7 +1825,7 @@ retry:
>   		num = (rem_sz > scatter_elem_sz_prev) ?
>   			scatter_elem_sz_prev : rem_sz;

> -		schp->pages[k] = alloc_pages(gfp_mask, order);
> +		schp->pages[k] = alloc_pages(gfp_mask | __GFP_ZERO, order);
>   		if (!schp->pages[k])
>   			goto out;


Can't find the corresponding bug.