cpufreq: cppc_cpufreq: Fix cppc_cpufreq_init() failure path

Kmemleak reported the below leak. When cppc_cpufreq_init went into
failure path, the cpu mask is not freed. After fix, this report is
gone. And to avaoid potential NULL pointer reference, check the cpu
value first.

unreferenced object 0xffff800fd5ea4880 (size 128):
  comm "swapper/0", pid 1, jiffies 4294939510 (age 668.680s)
  hex dump (first 32 bytes):
    00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00  .... ...........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffff0000082c4ae4>] __kmalloc_node+0x278/0x634
    [<ffff0000088f4a74>] alloc_cpumask_var_node+0x28/0x60
    [<ffff0000088f4af0>] zalloc_cpumask_var+0x14/0x1c
    [<ffff000008d20254>] cppc_cpufreq_init+0xd0/0x19c
    [<ffff000008083828>] do_one_initcall+0xec/0x15c
    [<ffff000008cd1018>] kernel_init_freeable+0x1f4/0x2a4
    [<ffff0000089099b0>] kernel_init+0x18/0x10c
    [<ffff000008084d50>] ret_from_fork+0x10/0x18
    [<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index a1c3025f9df77b91bfe278ca89ab16ebe3c295eb..8f7b21a4d537786eed76e41fe8ebdb42fac50efc 100644 (file)
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -230,8 +230,13 @@ static int __init cppc_cpufreq_init(void)
        return ret;
 
 out:
-       for_each_possible_cpu(i)
-               kfree(all_cpu_data[i]);
+       for_each_possible_cpu(i) {
+               cpu = all_cpu_data[i];
+               if (!cpu)
+                       break;
+               free_cpumask_var(cpu->shared_cpu_map);
+               kfree(cpu);
+       }
 
        kfree(all_cpu_data);
        return -ENODEV;