mm/vmpressure.c: use kstrndup instead of kmalloc+strncpy

Using kstrndup() simplifies the code.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Andy Shevchenko <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: David Rientjes <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

Author: andy-shev

mm/vmpressure.c

@@ -390,12 +390,11 @@ int vmpressure_register_event(struct mem_cgroup *memcg,
 	char *token;
 	int ret = 0;
 
-	spec_orig = spec = kzalloc(MAX_VMPRESSURE_ARGS_LEN + 1, GFP_KERNEL);
+	spec_orig = spec = kstrndup(args, MAX_VMPRESSURE_ARGS_LEN, GFP_KERNEL);
 	if (!spec) {
 		ret = -ENOMEM;
 		goto out;
 	}
-	strncpy(spec, args, MAX_VMPRESSURE_ARGS_LEN);
 
 	/* Find required level */
 	token = strsep(&spec, ",");