LU-2489 mdc: Restrict access to hsm_nl file

Disallow ordinary users from writing to /proc/fs/lustre/mdc/*/hsm_nl
to prevent denials of service.

Signed-off-by: John L. Hammond <jhammond@tacc.utexas.edu>
Change-Id: Ibd37cb9365bc4583fa964b18c3d87f264d1ca33d
Reviewed-on: http://review.whamcloud.com/4825
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Keith Mannthey <keith.mannthey@intel.com>
Reviewed-by: Richard Henwood <richard.henwood@intel.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lustre/mdc/lproc_mdc.c b/lustre/mdc/lproc_mdc.c
index 7c06298..4f25f36 100644 (file)
--- a/lustre/mdc/lproc_mdc.c
+++ b/lustre/mdc/lproc_mdc.c
@@ -161,7 +161,7 @@ static struct lprocfs_vars lprocfs_mdc_obd_vars[] = {
         { "timeouts",        lprocfs_rd_timeouts,    0, 0 },
         { "import",          lprocfs_rd_import,      lprocfs_wr_import, 0 },
         { "state",           lprocfs_rd_state,       0, 0 },
-        { "hsm_nl",          0, mdc_wr_kuc,          0, 0, 0222 },
+       { "hsm_nl",          0, mdc_wr_kuc,          0, 0, 0200 },
         { "pinger_recov",    lprocfs_rd_pinger_recov,
                              lprocfs_wr_pinger_recov, 0, 0 },
         { 0 }