307257cf47
When a cgroup is removed, it's unlinked from its parent's children list, but not actually freed until the last dentry on it is released (at which point cgrp->root->number_of_cgroups is decremented). Currently rebind_subsystems checks for the top cgroup's child list being empty in order to rebind subsystems into or out of a hierarchy - this can result in the set of subsystems bound to a hierarchy being removed-but-not-freed cgroup. The simplest fix for this is to forbid remounts that change the set of subsystems on a hierarchy that has removed-but-not-freed cgroups. This bug can be reproduced via: mkdir /mnt/cg mount -t cgroup -o ns,freezer cgroup /mnt/cg mkdir /mnt/cg/foo sleep 1h < /mnt/cg/foo & rmdir /mnt/cg/foo mount -t cgroup -o remount,ns,devices,freezer cgroup /mnt/cg kill $! Though the above will cause oops in -mm only but not mainline, but the bug can cause memory leak in mainline (and even oops) Signed-off-by: Paul Menage <menage@google.com> Reviewed-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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.. | ||
irq | ||
power | ||
time | ||
trace | ||
.gitignore | ||
acct.c | ||
audit_tree.c | ||
audit.c | ||
audit.h | ||
auditfilter.c | ||
auditsc.c | ||
backtracetest.c | ||
bounds.c | ||
capability.c | ||
cgroup_debug.c | ||
cgroup_freezer.c | ||
cgroup.c | ||
compat.c | ||
configs.c | ||
cpu.c | ||
cpuset.c | ||
delayacct.c | ||
dma-coherent.c | ||
dma.c | ||
exec_domain.c | ||
exit.c | ||
extable.c | ||
fork.c | ||
freezer.c | ||
futex_compat.c | ||
futex.c | ||
hrtimer.c | ||
itimer.c | ||
kallsyms.c | ||
Kconfig.freezer | ||
Kconfig.hz | ||
Kconfig.preempt | ||
kexec.c | ||
kfifo.c | ||
kgdb.c | ||
kmod.c | ||
kprobes.c | ||
ksysfs.c | ||
kthread.c | ||
latencytop.c | ||
lockdep_internals.h | ||
lockdep_proc.c | ||
lockdep.c | ||
Makefile | ||
marker.c | ||
module.c | ||
mutex-debug.c | ||
mutex-debug.h | ||
mutex.c | ||
mutex.h | ||
notifier.c | ||
ns_cgroup.c | ||
nsproxy.c | ||
panic.c | ||
params.c | ||
pid_namespace.c | ||
pid.c | ||
pm_qos_params.c | ||
posix-cpu-timers.c | ||
posix-timers.c | ||
printk.c | ||
profile.c | ||
ptrace.c | ||
rcuclassic.c | ||
rcupdate.c | ||
rcupreempt_trace.c | ||
rcupreempt.c | ||
rcutorture.c | ||
relay.c | ||
res_counter.c | ||
resource.c | ||
rtmutex_common.h | ||
rtmutex-debug.c | ||
rtmutex-debug.h | ||
rtmutex-tester.c | ||
rtmutex.c | ||
rtmutex.h | ||
rwsem.c | ||
sched_clock.c | ||
sched_cpupri.c | ||
sched_cpupri.h | ||
sched_debug.c | ||
sched_fair.c | ||
sched_features.h | ||
sched_idletask.c | ||
sched_rt.c | ||
sched_stats.h | ||
sched.c | ||
seccomp.c | ||
semaphore.c | ||
signal.c | ||
smp.c | ||
softirq.c | ||
softlockup.c | ||
spinlock.c | ||
srcu.c | ||
stacktrace.c | ||
stop_machine.c | ||
sys_ni.c | ||
sys.c | ||
sysctl_check.c | ||
sysctl.c | ||
taskstats.c | ||
test_kprobes.c | ||
time.c | ||
timeconst.pl | ||
timer.c | ||
tracepoint.c | ||
tsacct.c | ||
uid16.c | ||
user_namespace.c | ||
user.c | ||
utsname_sysctl.c | ||
utsname.c | ||
wait.c | ||
workqueue.c |