diff options
| author | Puneet Saxena <puneets@nvidia.com> | 2012-06-07 19:19:59 +0530 |
|---|---|---|
| committer | Simone Willett <swillett@nvidia.com> | 2012-07-13 14:44:57 -0700 |
| commit | ca7d8fa1906d2f2a2c311d337a14b328ed13c414 (patch) | |
| tree | a6b3d5a9dba30b267b12e1deb85d7e8726a0a788 /drivers/cpufreq | |
| parent | bf0e1f670b1ca8687890abaf7cf24e120a54415c (diff) | |
cpufreq: Protected access of policy attribute
It takes read RW semaphore to access policy governor
bug 997731
Change-Id: Ibdc3dd54cf6076c0fef4bc58f144e4bcb4631d76
Signed-off-by: Puneet Saxena <puneets@nvidia.com>
Reviewed-on: http://git-master/r/107079
GVS: Gerrit_Virtual_Submit
Reviewed-by: Sang-Hun Lee <sanlee@nvidia.com>
Reviewed-by: Peter Boonstoppel <pboonstoppel@nvidia.com>
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
Diffstat (limited to 'drivers/cpufreq')
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 629806dc5cbf..02e8c9120d6b 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1805,13 +1805,27 @@ int cpufreq_set_gov(char *target_gov, unsigned int cpu) if (!cur_policy) return -EINVAL; - new_policy = *cur_policy; - if (!strncmp(cur_policy->governor->name, target_gov, - strlen(target_gov))) { - /* Target governer & current governer is same */ + if (lock_policy_rwsem_read(cur_policy->cpu) < 0) { + ret = -EINVAL; + goto err_out; + } + + if (cur_policy->governor) + ret = strncmp(cur_policy->governor->name, target_gov, + strlen(target_gov)); + else { + unlock_policy_rwsem_read(cur_policy->cpu); + ret = -EINVAL; + goto err_out; + } + unlock_policy_rwsem_read(cur_policy->cpu); + + if (!ret) { + pr_debug(" Target governer & current governer is same\n"); ret = -EINVAL; goto err_out; } else { + new_policy = *cur_policy; if (cpufreq_parse_governor(target_gov, &new_policy.policy, &new_policy.governor)) { ret = -EINVAL; |