[syslog-ng] [PATCH (3.5)] system-source: Make /proc/kmsg optional

[Balazs Scheidler]

Hi,

Merged, thanks Gergely.

On Thu, 2013-05-16 at 14:35 +0200, Gergely Nagy wrote:
> In certain environments (vserver and OpenVZ come to mind), /proc/kmsg is
> not readable, not even for root. On these systems, emit a warning, and
> skip it, instead of aborting the startup.
> 
> Reported-by: Tamas Pal <folti at balabit.hu>
> Signed-off-by: Gergely Nagy <algernon at balabit.hu>
> ---
>  modules/system-source/system-source.c |   13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/modules/system-source/system-source.c b/modules/system-source/system-source.c
> index 3c72859..955ade7 100644
> --- a/modules/system-source/system-source.c
> +++ b/modules/system-source/system-source.c
> @@ -167,8 +167,17 @@ system_sysblock_add_linux_kmsg(GString *sysblock)
>        close (fd);
>      }
>  
> -  system_sysblock_add_file(sysblock, kmsg, -1,
> -                           "kernel", "kernel", format);
> +  if (access(kmsg, R_OK) == -1)
> +    {
> +      msg_warning("system(): The kernel message buffer is not readable, "
> +                  "please check permissions if this is unintentional.",
> +                  evt_tag_str("device", kmsg),
> +                  evt_tag_errno("error", errno),
> +                  NULL);
> +    }
> +  else
> +    system_sysblock_add_file(sysblock, kmsg, -1,
> +                             "kernel", "kernel", format);
>  }
>  
>  gboolean