Re: [PATCH] netlink: rate-limit leftover bytes warning and print process name

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 05/30/2014 04:57 PM, Michal Schmidt wrote:

> Any process is able to send netlink messages with leftover bytes.
> Make the warning rate-limited to prevent too much log spam.

> The warning is supposed to help find userspace bugs, so print the
> triggering command name to implicate the buggy program.

> Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
> ---
>   lib/nlattr.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)

> diff --git a/lib/nlattr.c b/lib/nlattr.c
> index fc67547..31047c4 100644
> --- a/lib/nlattr.c
> +++ b/lib/nlattr.c
> @@ -201,8 +201,9 @@ int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
>   	}
>
>   	if (unlikely(rem > 0))
> -		printk(KERN_WARNING "netlink: %d bytes leftover after parsing "
> -		       "attributes.\n", rem);
> +		printk_ratelimited(KERN_WARNING

    Better pr_warn_ratelimited().

> +				   "netlink: %d bytes leftover after parsing attributes in process `%s'.\n",
> +				   rem, current->comm);

WBR, Sergei