Re: [PATCH] random: Forbid llseek on random chardev

[Matt Mackall <mpm@selenic.com>]

On Sat, 2010-04-10 at 16:17 +0200, Frederic Weisbecker wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> Seeking on /dev/random and /dev/urandom is pointless.

It is indeed pointless, though that doesn't mean no one does it. 
Forbidding a no-op seems a rather unfriendly way to fix this.

> Using generic_file_llseek means we no longer need to
> take the BKL if anyone tries to seek on these.

Comment doesn't match the patch?

> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Cc: Matt Mackall <mpm@selenic.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
> ---
>  drivers/char/random.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/char/random.c b/drivers/char/random.c
> index 2fd3d39..513c685 100644
> --- a/drivers/char/random.c
> +++ b/drivers/char/random.c
> @@ -1169,6 +1169,7 @@ const struct file_operations random_fops = {
>  	.poll  = random_poll,
>  	.unlocked_ioctl = random_ioctl,
>  	.fasync = random_fasync,
> +	.open = nonseekable_open,
>  };
>  
>  const struct file_operations urandom_fops = {
> @@ -1176,6 +1177,7 @@ const struct file_operations urandom_fops = {
>  	.write = random_write,
>  	.unlocked_ioctl = random_ioctl,
>  	.fasync = random_fasync,
> +	.open = nonseekable_open,
>  };
>  
>  /***************************************************************



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