user/sven/linux.git/kernel/cgroup, branch v5.10.32

cgroup-v1: add disabled controller check in cgroup1_parse_param()

2021-02-17T10:02:25Z

[ Upstream commit 61e960b07b637f0295308ad91268501d744c21b5 ] When mounting a cgroup hierarchy with disabled controller in cgroup v1, all available controllers will be attached. For example, boot with cgroup_no_v1=cpu or cgroup_disable=cpu, and then mount with "mount -t cgroup -ocpu cpu /sys/fs/cgroup/cpu", then all enabled controllers will be attached except cpu. Fix this by adding disabled controller check in cgroup1_parse_param(). If the specified controller is disabled, just return error with information "Disabled controller xx" rather than attaching all the other enabled controllers. Fixes: f5dfb5315d34 ("cgroup: take options parsing into ->parse_monolithic()") Signed-off-by: Chen Zhou Reviewed-by: Zefan Li Reviewed-by: Michal Koutný Signed-off-by: Tejun Heo Signed-off-by: Sasha Levin

cgroup: fix psi monitor for root cgroup

2021-02-17T10:02:21Z

commit 385aac1519417b89cb91b77c22e4ca21db563cd0 upstream. Fix NULL pointer dereference when adding new psi monitor to the root cgroup. PSI files for root cgroup was introduced in df5ba5be742 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 Reviewed-by: Suren Baghdasaryan Acked-by: Dan Schatzberg Fixes: df5ba5be7425 ("kernel/sched/psi.c: expose pressure metrics on root cgroup") Acked-by: Johannes Weiner Cc: stable@vger.kernel.org # 5.2+ Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

cgroup: Fix memory leak when parsing multiple source parameters

2021-01-06T13:56:51Z

commit 2d18e54dd8662442ef5898c6bdadeaf90b3cebbc upstream. A memory leak is found in cgroup1_parse_param() when multiple source parameters overwrite fc->source in the fs_context struct without free. unreferenced object 0xffff888100d930e0 (size 16): comm "mount", pid 520, jiffies 4303326831 (age 152.783s) hex dump (first 16 bytes): 74 65 73 74 6c 65 61 6b 00 00 00 00 00 00 00 00 testleak........ backtrace: [<000000003e5023ec>] kmemdup_nul+0x2d/0xa0 [<00000000377dbdaa>] vfs_parse_fs_string+0xc0/0x150 [<00000000cb2b4882>] generic_parse_monolithic+0x15a/0x1d0 [<000000000f750198>] path_mount+0xee1/0x1820 [<0000000004756de2>] do_mount+0xea/0x100 [<0000000094cafb0a>] __x64_sys_mount+0x14b/0x1f0 Fix this bug by permitting a single source parameter and rejecting with an error all subsequent ones. Fixes: 8d2451f4994f ("cgroup1: switch to option-by-option parsing") Reported-by: Hulk Robot Signed-off-by: Qinglang Miao Reviewed-by: Zefan Li Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

cpuset: fix race between hotplug work and later CPU offline

2020-12-30T10:54:11Z

commit 406100f3da08066c00105165db8520bbc7694a36 upstream. One of our machines keeled over trying to rebuild the scheduler domains. Mainline produces the same splat: BUG: unable to handle page fault for address: 0000607f820054db CPU: 2 PID: 149 Comm: kworker/1:1 Not tainted 5.10.0-rc1-master+ #6 Workqueue: events cpuset_hotplug_workfn RIP: build_sched_domains Call Trace: partition_sched_domains_locked rebuild_sched_domains_locked cpuset_hotplug_workfn It happens with cgroup2 and exclusive cpusets only. This reproducer triggers it on an 8-cpu vm and works most effectively with no preexisting child cgroups: cd $UNIFIED_ROOT mkdir cg1 echo 4-7 > cg1/cpuset.cpus echo root > cg1/cpuset.cpus.partition # with smt/control reading 'on', echo off > /sys/devices/system/cpu/smt/control RIP maps to sd->shared = *per_cpu_ptr(sdd->sds, sd_id); from sd_init(). sd_id is calculated earlier in the same function: cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu)); sd_id = cpumask_first(sched_domain_span(sd)); tl->mask(cpu), which reads cpu_sibling_map on x86, returns an empty mask and so cpumask_first() returns >= nr_cpu_ids, which leads to the bogus value from per_cpu_ptr() above. The problem is a race between cpuset_hotplug_workfn() and a later offline of CPU N. cpuset_hotplug_workfn() updates the effective masks when N is still online, the offline clears N from cpu_sibling_map, and then the worker uses the stale effective masks that still have N to generate the scheduling domains, leading the worker to read N's empty cpu_sibling_map in sd_init(). rebuild_sched_domains_locked() prevented the race during the cgroup2 cpuset series up until the Fixes commit changed its check. Make the check more robust so that it can detect an offline CPU in any exclusive cpuset's effective mask, not just the top one. Fixes: 0ccea8feb980 ("cpuset: Make generate_sched_domains() work with partition") Signed-off-by: Daniel Jordan Signed-off-by: Peter Zijlstra (Intel) Acked-by: Tejun Heo Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20201112171711.639541-1-daniel.m.jordan@oracle.com Signed-off-by: Greg Kroah-Hartman

kernel/: fix repeated words in comments

2020-10-16T18:11:19Z

Fix multiple occurrences of duplicated words in kernel/. Fix one typo/spello on the same line as a duplicate word. Change one instance of "the the" to "that the". Otherwise just drop one of the repeated words. Signed-off-by: Randy Dunlap Signed-off-by: Andrew Morton Link: https://lkml.kernel.org/r/98202fa6-8919-ef63-9efe-c0fad5ca7af1@infradead.org Signed-off-by: Linus Torvalds

cgroup: Zero sized write should be no-op

2020-09-30T17:52:06Z

Do not report failure on zero sized writes, and handle them as no-op. There's issues for example in case of writev() when there's iovec containing zero buffer as a first one. It's expected writev() on below example to successfully perform the write to specified writable cgroup file expecting integer value, and to return 2. For now it's returning value -1, and skipping the write: int writetest(int fd) { const char *buf1 = ""; const char *buf2 = "1\n"; struct iovec iov[2] = { { .iov_base = (void*)buf1, .iov_len = 0 }, { .iov_base = (void*)buf2, .iov_len = 2 } }; return writev(fd, iov, 2); } This patch fixes the issue by checking if there's nothing to write, and handling the write as no-op by just returning 0. Signed-off-by: Jouni Roivas Signed-off-by: Tejun Heo

cgroup: remove redundant kernfs_activate in cgroup_setup_root()

2020-09-30T16:03:10Z

This step is already done in rebind_subsystems(). Not necessary to do it again. Signed-off-by: Wei Yang Signed-off-by: Tejun Heo

Merge tag 'for-5.9/block-20200802' of git://git.kernel.dk/linux-block

2020-08-03T18:57:03Z

Pull core block updates from Jens Axboe: "Good amount of cleanups and tech debt removals in here, and as a result, the diffstat shows a nice net reduction in code. - Softirq completion cleanups (Christoph) - Stop using ->queuedata (Christoph) - Cleanup bd claiming (Christoph) - Use check_events, moving away from the legacy media change (Christoph) - Use inode i_blkbits consistently (Christoph) - Remove old unused writeback congestion bits (Christoph) - Cleanup/unify submission path (Christoph) - Use bio_uninit consistently, instead of bio_disassociate_blkg (Christoph) - sbitmap cleared bits handling (John) - Request merging blktrace event addition (Jan) - sysfs add/remove race fixes (Luis) - blk-mq tag fixes/optimizations (Ming) - Duplicate words in comments (Randy) - Flush deferral cleanup (Yufen) - IO context locking/retry fixes (John) - struct_size() usage (Gustavo) - blk-iocost fixes (Chengming) - blk-cgroup IO stats fixes (Boris) - Various little fixes" * tag 'for-5.9/block-20200802' of git://git.kernel.dk/linux-block: (135 commits) block: blk-timeout: delete duplicated word block: blk-mq-sched: delete duplicated word block: blk-mq: delete duplicated word block: genhd: delete duplicated words block: elevator: delete duplicated word and fix typos block: bio: delete duplicated words block: bfq-iosched: fix duplicated word iocost_monitor: start from the oldest usage index iocost: Fix check condition of iocg abs_vdebt block: Remove callback typedefs for blk_mq_ops block: Use non _rcu version of list functions for tag_set_list blk-cgroup: show global disk stats in root cgroup io.stat blk-cgroup: make iostat functions visible to stat printing block: improve discard bio alignment in __blkdev_issue_discard() block: change REQ_OP_ZONE_RESET and REQ_OP_ZONE_RESET_ALL to be odd numbers block: defer flush request no matter whether we have elevator block: make blk_timeout_init() static block: remove retry loop in ioc_release_fn() block: remove unnecessary ioc nested locking block: integrate bd_start_claiming into __blkdev_get ...

cgroup: fix cgroup_sk_alloc() for sk_clone_lock()

2020-07-07T20:34:11Z

When we clone a socket in sk_clone_lock(), its sk_cgrp_data is copied, so the cgroup refcnt must be taken too. And, unlike the sk_alloc() path, sock_update_netprioidx() is not called here. Therefore, it is safe and necessary to grab the cgroup refcnt even when cgroup_sk_alloc is disabled. sk_clone_lock() is in BH context anyway, the in_interrupt() would terminate this function if called there. And for sk_alloc() skcd->val is always zero. So it's safe to factor out the code to make it more readable. The global variable 'cgroup_sk_alloc_disabled' is used to determine whether to take these reference counts. It is impossible to make the reference counting correct unless we save this bit of information in skcd->val. So, add a new bit there to record whether the socket has already taken the reference counts. This obviously relies on kmalloc() to align cgroup pointers to at least 4 bytes, ARCH_KMALLOC_MINALIGN is certainly larger than that. This bug seems to be introduced since the beginning, commit d979a39d7242 ("cgroup: duplicate cgroup reference when cloning sockets") tried to fix it but not compeletely. It seems not easy to trigger until the recent commit 090e28b229af ("netprio_cgroup: Fix unlimited memory leak of v2 cgroups") was merged. Fixes: bd1060a1d671 ("sock, cgroup: add sock->sk_cgroup") Reported-by: Cameron Berkenpas Reported-by: Peter Geis Reported-by: Lu Fengqi Reported-by: Daniël Sonck Reported-by: Zhang Qiang Tested-by: Cameron Berkenpas Tested-by: Peter Geis Tested-by: Thomas Lamprecht Cc: Daniel Borkmann Cc: Zefan Li Cc: Tejun Heo Cc: Roman Gushchin Signed-off-by: Cong Wang Signed-off-by: David S. Miller

cgroup: unexport cgroup_rstat_updated

2020-06-29T15:09:08Z

cgroup_rstat_updated is only used by core block code, no need to export it. Acked-by: Tejun Heo Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe