Re: [PATCH v14 08/17] splice: Do splice read from a file without using ITER_PIPE

From: Alexander Egorenkov
Date: Sat Feb 18 2023 - 03:29:49 EST


Hi David,


David Howells <dhowells@xxxxxxxxxx> writes:

> Does the attached fix the problem for you? The data being written into the
> pipe needs to be limited to the size of the file.
>
> David
>
> diff --git a/mm/filemap.c b/mm/filemap.c
> index c01bbcb9fa92..6362ac697a70 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -2948,7 +2948,8 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos,
> if (writably_mapped)
> flush_dcache_folio(folio);
>
> - n = splice_folio_into_pipe(pipe, folio, *ppos, len);
> + n = min_t(loff_t, len, isize - *ppos);
> + n = splice_folio_into_pipe(pipe, folio, *ppos, n);
> if (!n)
> goto out;
> len -= n;

Yes, this change fixed the problem.

Thanks
Regards
Alex