Re: [PATCH v2] pipe: Fail cleanly when root tries F_SETPIPE_SZ withbig size

[Pekka Enberg]

On Sat, Nov 19, 2011 at 9:34 AM, Sasha Levin <levinsasha928@xxxxxxxxx> wrote:
> When a user with the CAP_SYS_RESOURCE cap tries to F_SETPIPE_SZ a pipe with
> size bigger than what kmalloc() can alloc it spits out an ugly warning:

[snip]

> Instead, make kcalloc() handle the overflow case and fail quietly.
>
> Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
> Cc: Pekka Enberg <penberg@xxxxxxxxxx>
> Cc: linux-fsdevel@xxxxxxxxxxxxxxx
> Signed-off-by: Sasha Levin <levinsasha928@xxxxxxxxx>

Acked-by: Pekka Enberg <penberg@xxxxxxxxxx>

> ---
>  fs/pipe.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/fs/pipe.c b/fs/pipe.c
> index 4065f07..3e38dc6 100644
> --- a/fs/pipe.c
> +++ b/fs/pipe.c
> @@ -1137,7 +1137,7 @@ static long pipe_set_size(struct pipe_inode_info *pipe, unsigned long nr_pages)
>        if (nr_pages < pipe->nrbufs)
>                return -EBUSY;
>
> -       bufs = kcalloc(nr_pages, sizeof(struct pipe_buffer), GFP_KERNEL);
> +       bufs = kcalloc(nr_pages, sizeof(struct pipe_buffer), GFP_KERNEL | __GFP_NOWARN);
>        if (unlikely(!bufs))
>                return -ENOMEM;
>
> --
> 1.7.8.rc1
>
> --
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