The cpu variable is still being used in the of_get_property() call
after the of_node_put() call, which may result in use-after-free.
Fixes: a9acc26b75f ("cpufreq/pasemi: fix possible object reference leak")
Signed-off-by: Wen Yang <wen.yan...@zte.com.cn>
Cc: "Rafael J. Wysocki" <r...@rjwysocki.net>
Cc: Viresh Kumar <viresh.ku...@linaro.org>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: linuxppc-...@lists.ozlabs.org
Cc: linux...@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
v5: put together the code to get, use, and release cpu device_node.
v4: restore the blank line.
v3: fix a leaked reference.
v2: clean up the code according to the advice of viresh.
drivers/cpufreq/pasemi-cpufreq.c | 21 +++++++++------------
1 file changed, 9 insertions(+), 12 deletions(-)
diff --git a/drivers/cpufreq/pasemi-cpufreq.c b/drivers/cpufreq/pasemi-cpufreq.c
index 6b1e4ab..1f0beb7 100644
--- a/drivers/cpufreq/pasemi-cpufreq.c
+++ b/drivers/cpufreq/pasemi-cpufreq.c
@@ -131,10 +131,17 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy
*policy)
int err = -ENODEV;
cpu = of_get_cpu_node(policy->cpu, NULL);
-
- of_node_put(cpu);
if (!cpu)
goto out;
+ max_freqp = of_get_property(cpu, "clock-frequency", NULL);
+ of_node_put(cpu);
+ if (!max_freqp) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ /* we need the freq in kHz */
+ max_freq = *max_freqp / 1000;
dn = of_find_compatible_node(NULL, NULL, "1682m-sdc");
if (!dn)
@@ -171,16 +178,6 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy
*policy)
}
pr_debug("init cpufreq on CPU %d\n", policy->cpu);
-
- max_freqp = of_get_property(cpu, "clock-frequency", NULL);
- if (!max_freqp) {
- err = -EINVAL;
- goto out_unmap_sdcpwr;
- }
-
- /* we need the freq in kHz */
- max_freq = *max_freqp / 1000;
-
pr_debug("max clock-frequency is at %u kHz\n", max_freq);
pr_debug("initializing frequency table\n");
--
2.9.5
