[PATCH] VM: add capabilites check to set_zone_reclaim

Add a capability check to sys_set_zone_reclaim().  This syscall is not
something that should be available to a user.
Signed-off-by: NMartin Hicks <mort@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

include/linux/capability.h

@@ -233,6 +233,7 @@ typedef __u32 kernel_cap_t;
 /* Allow enabling/disabling tagged queuing on SCSI controllers and sending
    arbitrary SCSI commands */
 /* Allow setting encryption key on loopback filesystem */
+/* Allow setting zone reclaim policy */
 
 #define CAP_SYS_ADMIN        21
 

mm/vmscan.c

@@ -1375,6 +1375,9 @@ asmlinkage long sys_set_zone_reclaim(unsigned int node, unsigned int zone,
 	struct zone *z;
 	int i;
 
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
 	if (node >= MAX_NUMNODES || !node_online(node))
 		return -EINVAL;