| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 9 Sep 2015 18:27:31 +0800 From: Chen Yu <yu.c.chen@...el.com> To: kristen@...ux.intel.com, rjw@...ysocki.net, viresh.kumar@...aro.org Cc: s.ikarashi@...fujitsu.com, rui.zhang@...el.com, linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org, Chen Yu <yu.c.chen@...el.com> Subject: [PATCH] [v2] intel_pstate: Fix user input of min/max to legal policy region In current code, max_perf_pct might be smaller than min_perf_pct by improper user input: $ grep . /sys/devices/system/cpu/intel_pstate/m*_perf_pct /sys/devices/system/cpu/intel_pstate/max_perf_pct:100 /sys/devices/system/cpu/intel_pstate/min_perf_pct:100 $ echo 80 > /sys/devices/system/cpu/intel_pstate/max_perf_pct $ grep . /sys/devices/system/cpu/intel_pstate/m*_perf_pct /sys/devices/system/cpu/intel_pstate/max_perf_pct:80 /sys/devices/system/cpu/intel_pstate/min_perf_pct:100 Fix this problem by 2 steps: 1.Normalize the user input to [min_policy, max_policy]. 2.Make sure max_perf_pct>=min_perf_pct, suggested by Seiichi Ikarashi. Signed-off-by: Chen Yu <yu.c.chen@...el.com> --- v2: - Add logic to ensure max_perf_pct>=min_perf_pct. --- drivers/cpufreq/intel_pstate.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index fcb929e..a0b935f 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -423,6 +423,8 @@ static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b, limits.max_sysfs_pct = clamp_t(int, input, 0 , 100); limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct); + limits.max_perf_pct = max(limits.min_policy_pct, limits.max_perf_pct); + limits.max_perf_pct = max(limits.min_perf_pct, limits.max_perf_pct); limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100)); if (hwp_active) @@ -442,6 +444,8 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b, limits.min_sysfs_pct = clamp_t(int, input, 0 , 100); limits.min_perf_pct = max(limits.min_policy_pct, limits.min_sysfs_pct); + limits.min_perf_pct = min(limits.max_policy_pct, limits.min_perf_pct); + limits.min_perf_pct = min(limits.max_perf_pct, limits.min_perf_pct); limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100)); if (hwp_active) @@ -985,12 +989,19 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) limits.min_policy_pct = (policy->min * 100) / policy->cpuinfo.max_freq; limits.min_policy_pct = clamp_t(int, limits.min_policy_pct, 0 , 100); - limits.min_perf_pct = max(limits.min_policy_pct, limits.min_sysfs_pct); - limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100)); - limits.max_policy_pct = (policy->max * 100) / policy->cpuinfo.max_freq; limits.max_policy_pct = clamp_t(int, limits.max_policy_pct, 0 , 100); + + /* Normalize user input to [min_policy_pct, max_policy_pct] */ + limits.min_perf_pct = max(limits.min_policy_pct, limits.min_sysfs_pct); + limits.min_perf_pct = min(limits.max_policy_pct, limits.min_perf_pct); limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct); + limits.max_perf_pct = max(limits.min_policy_pct, limits.max_perf_pct); + + /* Make sure min_perf_pct <= max_perf_pct */ + limits.min_perf_pct = min(limits.max_perf_pct, limits.min_perf_pct); + + limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100)); limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100)); if (hwp_active) -- 1.8.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists