linux/kernel/sched
Quentin Perret 6d2f8909a5 sched: Fix out-of-bound access in uclamp
Util-clamp places tasks in different buckets based on their clamp values
for performance reasons. However, the size of buckets is currently
computed using a rounding division, which can lead to an off-by-one
error in some configurations.

For instance, with 20 buckets, the bucket size will be 1024/20=51. A
task with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly,
correct indexes are in range [0,19], hence leading to an out of bound
memory access.

Clamp the bucket id to fix the issue.

Fixes: 69842cba9a ("sched/uclamp: Add CPU's clamp buckets refcounting")
Suggested-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lkml.kernel.org/r/20210430151412.160913-1-qperret@google.com
2021-05-06 15:33:26 +02:00
..
autogroup.c sched/autogroup: Make autogroup_path() always available 2019-06-24 19:23:40 +02:00
autogroup.h
clock.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
completion.c completion: Use lockdep_assert_RT_in_threaded_ctx() in complete_all() 2020-03-23 18:40:25 +01:00
core.c sched: Fix out-of-bound access in uclamp 2021-05-06 15:33:26 +02:00
cpuacct.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
cpudeadline.c sched,rt: Use the full cpumask for balancing 2020-11-10 18:39:00 +01:00
cpudeadline.h
cpufreq_schedutil.c Scheduler updates for this cycle are: 2021-04-28 13:33:57 -07:00
cpufreq.c cpufreq: Avoid leaving stale IRQ work items during CPU offline 2019-12-12 17:59:43 +01:00
cpupri.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
cpupri.h sched/cpupri: Add CPUPRI_HIGHER 2020-10-29 11:00:30 +01:00
cputime.c Scheduler updates for this cycle are: 2021-04-28 13:33:57 -07:00
deadline.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
debug.c sched/debug: Fix cgroup_path[] serialization 2021-04-21 13:55:42 +02:00
fair.c kthread: Fix PF_KTHREAD vs to_kthread() race 2021-04-21 13:55:42 +02:00
features.h sched: Warn on long periods of pending need_resched 2021-04-21 13:55:41 +02:00
idle.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
isolation.c isolcpus: Affine unbound kernel threads to housekeeping cpus 2020-06-15 14:10:03 +02:00
loadavg.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
Makefile kcsan: Improve various small stylistic details 2019-11-20 10:47:23 +01:00
membarrier.c sched/membarrier: fix missing local execution of ipi_sync_rq_state() 2021-03-06 12:40:21 +01:00
pelt.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
pelt.h sched: Fix various typos 2021-03-22 00:11:52 +01:00
psi.c psi: Fix psi state corruption when schedule() races with cgroup move 2021-05-06 15:33:26 +02:00
rt.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
sched-pelt.h sched/fair: Fix "runnable_avg_yN_inv" not used warnings 2019-06-17 12:15:58 +02:00
sched.h sched: Warn on long periods of pending need_resched 2021-04-21 13:55:41 +02:00
smp.h sched/headers: Split out open-coded prototypes into kernel/sched/smp.h 2020-05-28 11:03:20 +02:00
stats.c sched: Fix various typos 2021-03-22 00:11:52 +01:00
stats.h psi: Optimize task switch inside shared cgroups 2021-03-06 12:40:23 +01:00
stop_task.c sched: Remove select_task_rq()'s sd_flag parameter 2020-11-10 18:39:06 +01:00
swait.c sched/swait: Prepare usage in completions 2020-03-21 16:00:23 +01:00
topology.c sched/debug: Rename the sched_debug parameter to sched_verbose 2021-04-17 13:22:44 +02:00
wait_bit.c sched/wait: fix ___wait_var_event(exclusive) 2019-12-17 13:32:50 +01:00
wait.c sched/wait: Add add_wait_queue_priority() 2020-11-15 09:49:09 -05:00