Re: [PATCH] fix page leak during core dump

[David Howells <dhowells@redhat.com>]

Andrew Morton <akpm@linux-foundation.org> wrote:

> <would anyone be interested in hearing my opinion on the DUMP_SEEK macro
> again?>

I can guess.  And it's very probably right.  Macros containing return
statements like that are dodgy as they help people screw up the error handling.

However, ...

Andrew Morton <akpm@linux-foundation.org> wrote:

> -				DUMP_SEEK(file->f_pos + PAGE_SIZE);
> -				page_cache_release(page);
> +				if (!dump_seek(file, file->f_pos + PAGE_SIZE)) {
> +					page_cache_release(page);
> +					return 0;
> +				}

Is not correct as you've then eliminated the page_cache_release() on the
success path.  What you probably intended was:

	int tmp;
	...
				tmp = dump_seek(file, file->f_pos + PAGE_SIZE);
				page_cache_release(page);
				if (!tmp)
					return 0;

David