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

Using kstrndup() simplifies the code.

Link: http://lkml.kernel.org/r/20180503201807.24941-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index 85350ce..7142207 100644 (file)
--- a/mm/vmpressure.c
+++ b/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, ",");