[syslog-ng] [PATCH 1/7] [persist]: only check the buffer size if no encoding is specified

[Balazs Scheidler]

Hi,

Can you please explain when this causes problems and what the problem
is? Does it perhaps need to be backported to earlier versions?

Also, some sanity check on raw_buffer_size would be needed, as we try to
allocate that size from the stack, which is limited in size.

On Mon, 2011-05-23 at 11:56 +0200, Gergely Nagy wrote:
> From: Peter Gyorko <gyorkop at balabit.hu>
> 
> If no encoding is specified, we read directly into our buffer,
> therefore need to verify the buffer sizes. If we do use encoding, the
> raw buffer size cannot be directly compared to our own buffer size.
> 
> Therefore, only validate the buffer size if no encoding is specified,
> because otherwise it doesn't make sense.
> 
> Signed-off-by: Viktor Juhasz <jviktor at balabit.hu>
> Signed-off-by: Peter Gyorko <gyorkop at balabit.hu>
> ---
>  lib/logproto.c |   14 +++++++-------
>  1 files changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/lib/logproto.c b/lib/logproto.c
> index d526357..6e81892 100644
> --- a/lib/logproto.c
> +++ b/lib/logproto.c
> @@ -651,16 +651,16 @@ log_proto_buffered_server_apply_state(LogProtoBufferedServer *self, PersistEntry
>        gssize rc;
>        guchar *raw_buffer;
>  
> -      if (state->raw_buffer_size > state->buffer_size)
> -        {
> -          msg_notice("Invalid raw_buffer_size member in LogProtoBufferedServer state, restarting from the beginning",
> -                     evt_tag_str("state", persist_name),
> -                     NULL);
> -          goto error;
> -        }
>        if (!self->super.encoding)
>          {
>            /* no conversion, we read directly into our buffer */
> +          if (state->raw_buffer_size > state->buffer_size)
> +            {
> +              msg_notice("Invalid raw_buffer_size member in LogProtoBufferedServer state, restarting from the beginning",
> +                         evt_tag_str("state", persist_name),
> +                         NULL);
> +              goto error;
> +            }
>            raw_buffer = self->buffer;
>          }
>        else

-- 
Bazsi