Odin Ugedal e72a65802a cgroup: fix psi monitor for root cgroup ... commit 385aac1519417b89cb91b77c22e4ca21db563cd0 upstream. Fix NULL pointer dereference when adding new psi monitor to the root cgroup. PSI files for root cgroup was introduced in df5ba5be74 by using system wide psi struct when reading, but file write/monitor was not properly fixed. Since the PSI config for the root cgroup isn't initialized, the current implementation tries to lock a NULL ptr, resulting in a crash. Can be triggered by running this as root: $ tee /sys/fs/cgroup/cpu.pressure <<< "some 10000 1000000" Signed-off-by: Odin Ugedal <odin@uged.al> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Dan Schatzberg <dschatzberg@fb.com> Fixes: df5ba5be74 ("kernel/sched/psi.c: expose pressure metrics on root cgroup") Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: stable@vger.kernel.org # 5.2+ Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-02-17 11:02:21 +01:00
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cgroup-internal.h	fs_parse: fold fs_parameter_desc/fs_parameter_spec	2020-02-07 14:48:37 -05:00
cgroup-v1.c	cgroup: Fix memory leak when parsing multiple source parameters	2021-01-06 14:56:51 +01:00
cgroup.c	cgroup: fix psi monitor for root cgroup	2021-02-17 11:02:21 +01:00
cpuset.c	cpuset: fix race between hotplug work and later CPU offline	2020-12-30 11:54:11 +01:00
debug.c	kernel: cgroup: fix misuse of %x	2019-05-06 08:47:48 -07:00
freezer.c	cgroup: freezer: don't change task and cgroups status unnecessarily	2019-11-07 07:38:41 -08:00
legacy_freezer.c	cgroup: rename freezer.c into legacy_freezer.c	2019-04-19 11:26:48 -07:00
Makefile	cgroup: cgroup v2 freezer	2019-04-19 11:26:48 -07:00
namespace.c	nsproxy: add struct nsset	2020-05-09 13:57:12 +02:00
pids.c	clone3: allow spawning processes into cgroups	2020-02-12 17:57:51 -05:00
rdma.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 451	2019-06-19 17:09:08 +02:00
rstat.c	cgroup: unexport cgroup_rstat_updated	2020-06-29 09:09:08 -06:00