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Date: Thu, 6 Sep 2018 00:00:48 +0200
From: Dominique Martinet <asmadeus@codewreck.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Omar Sandoval <osandov@osandov.com>, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Eric Biederman <ebiederm@xmission.com>,
        James Morse <james.morse@arm.com>,
        Bhupesh Sharma <bhsharma@redhat.com>, kernel-team@fb.com
Subject: Re: [PATCH v3] proc/kcore: fix invalid memory access in multi-page
 read optimization
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Andrew Morton wrote on Wed, Sep 05, 2018:
> lgtm.  Let's add a nice little why-were-doing-this?

Sure, thank you.

> --- a/fs/proc/kcore.c~proc-kcore-fix-invalid-memory-access-in-multi-page-read-optimization-v3-fix
> +++ a/fs/proc/kcore.c
> @@ -464,7 +464,7 @@ read_kcore(struct file *file, char __use
>  				ret = -EFAULT;
>  				goto out;
>  			}
> -			m = NULL;
> +			m = NULL;	/* skip the list anchor */
>  		} else if (m->type == KCORE_VMALLOC) {
>  			vread(buf, (char *)start, tsz);
>  			/* we have to zero-fill user buffer even if no read */

-- 
Dominique