linux-stable/block
Carlo Nonato 3cbfc33d43 block, bfq: fix overwrite of bfq_group pointer in bfq_find_set_group()
[ Upstream commit 14afc59361 ]

The bfq_find_set_group() function takes as input a blkcg (which represents
a cgroup) and retrieves the corresponding bfq_group, then it updates the
bfq internal group hierarchy (see comments inside the function for why
this is needed) and finally it returns the bfq_group.
In the hierarchy update cycle, the pointer holding the correct bfq_group
that has to be returned is mistakenly used to traverse the hierarchy
bottom to top, meaning that in each iteration it gets overwritten with the
parent of the current group. Since the update cycle stops at root's
children (depth = 2), the overwrite becomes a problem only if the blkcg
describes a cgroup at a hierarchy level deeper than that (depth > 2). In
this case the root's child that happens to be also an ancestor of the
correct bfq_group is returned. The main consequence is that processes
contained in a cgroup at depth greater than 2 are wrongly placed in the
group described above by BFQ.

This commits fixes this problem by using a different bfq_group pointer in
the update cycle in order to avoid the overwrite of the variable holding
the original group reference.

Reported-by: Kwon Je Oh <kwonje.oh2@gmail.com>
Signed-off-by: Carlo Nonato <carlo.nonato95@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-03-25 08:06:08 +01:00
..
partitions partitions/aix: append null character to print data from disk 2018-07-27 09:17:41 -06:00
badblocks.c badblocks: fix wrong return value in badblocks_set if badblocks are disabled 2017-11-03 11:29:50 -07:00
bfq-cgroup.c block, bfq: fix overwrite of bfq_group pointer in bfq_find_set_group() 2020-03-25 08:06:08 +01:00
bfq-iosched.c blok, bfq: do not plug I/O if all queues are weight-raised 2019-11-20 18:46:44 +01:00
bfq-iosched.h block, bfq: inject other-queue I/O into seeky idle queues on NCQ flash 2019-11-20 18:46:44 +01:00
bfq-wf2q.c block, bfq: correctly charge and reset entity service in all cases 2018-11-13 11:08:28 -08:00
bio-integrity.c block/bio-integrity: fix a memory leak bug 2019-07-31 07:27:08 +02:00
bio.c block: do not leak memory in bio_copy_user_iov() 2019-04-17 08:38:51 +02:00
blk-cgroup.c blkcg: make blkcg_print_stat() print stats only for online blkgs 2019-11-12 19:21:19 +01:00
blk-core.c block: call rq_qos_exit() after queue is frozen 2019-12-01 09:17:06 +01:00
blk-exec.c blk-mq-sched: remove unused 'can_block' arg from blk_mq_sched_insert_request 2018-01-17 09:49:21 -07:00
blk-flush.c block: fix null pointer dereference in blk_mq_rq_timed_out() 2019-10-05 13:10:08 +02:00
blk-integrity.c block drivers/block: Use octal not symbolic permissions 2018-05-24 13:38:59 -06:00
blk-ioc.c block, mm: remove unnecessary __GFP_HIGH flag 2018-07-09 09:07:54 -06:00
blk-iolatency.c blk-iolatency: fix STS_AGAIN handling 2019-09-16 08:21:41 +02:00
blk-lib.c block: fix 32 bit overflow in __blkdev_issue_discard() 2020-02-01 09:37:12 +00:00
blk-map.c block: fix memleak when __blk_rq_map_user_iov() is failed 2020-01-12 12:17:22 +01:00
blk-merge.c block: don't use bio->bi_vcnt to figure out segment number 2020-01-27 14:50:23 +01:00
blk-mq-cpumap.c blk-mq: don't keep offline CPUs mapped to hctx 0 2018-04-10 08:38:46 -06:00
blk-mq-debugfs-zoned.c block: Make struct request_queue smaller for CONFIG_BLK_DEV_ZONED=n 2018-07-09 09:07:52 -06:00
blk-mq-debugfs.c block, scsi: Change the preempt-only flag into a counter 2019-08-04 09:30:57 +02:00
blk-mq-debugfs.h block: Make struct request_queue smaller for CONFIG_BLK_DEV_ZONED=n 2018-07-09 09:07:52 -06:00
blk-mq-pci.c blk-mq: code clean-up by adding an API to clear set->mq_map 2018-07-09 09:07:53 -06:00
blk-mq-rdma.c block: Add rdma affinity based queue mapping helper 2017-08-08 14:58:03 -04:00
blk-mq-sched.c block: mq-deadline: Fix write completion handling 2019-01-13 09:51:07 +01:00
blk-mq-sched.h block: mq-deadline: Fix write completion handling 2019-01-13 09:51:07 +01:00
blk-mq-sysfs.c blk-mq: make sure that line break can be printed 2019-12-17 20:35:48 +01:00
blk-mq-tag.c blk-mq: Allow blocking queue tag iter callbacks 2018-09-25 20:17:59 -06:00
blk-mq-tag.h Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block 2017-11-14 15:32:19 -08:00
blk-mq-virtio.c
blk-mq.c block: fix null pointer dereference in blk_mq_rq_timed_out() 2019-10-05 13:10:08 +02:00
blk-mq.h blk-mq: free hw queue's resource in hctx's release handler 2019-09-16 08:22:13 +02:00
blk-rq-qos.c blk-wbt: fix performance regression in wbt scale_up/scale_down 2019-10-17 13:45:16 -07:00
blk-rq-qos.h blk-rq-qos: fix first node deletion of rq_qos_del() 2019-10-29 09:20:09 +01:00
blk-settings.c block: fix an integer overflow in logical block size 2020-01-23 08:21:29 +01:00
blk-softirq.c block: fix timeout changes for legacy request drivers 2018-06-19 11:27:18 -06:00
blk-stat.c blk-stat: export helpers for modifying blk_rq_stat 2018-07-09 09:07:54 -06:00
blk-stat.h block: deactivate blk_stat timer in wbt_disable_default() 2019-01-13 09:51:06 +01:00
blk-sysfs.c block: call rq_qos_exit() after queue is frozen 2019-12-01 09:17:06 +01:00
blk-tag.c for-linus-20180616 2018-06-17 05:37:55 +09:00
blk-throttle.c blk-throttle: fix zero wait time for iops throttled group 2019-07-26 09:14:30 +02:00
blk-timeout.c blk-mq: Fix timeout handling in case the timeout handler returns BLK_EH_DONE 2018-06-23 10:25:45 -06:00
blk-wbt.c blk-wbt: fix performance regression in wbt scale_up/scale_down 2019-10-17 13:45:16 -07:00
blk-wbt.h block: remove external dependency on wbt_flags 2018-07-09 09:07:54 -06:00
blk-zoned.c block: Remove a superfluous cast from blkdev_report_zones() 2018-07-09 09:07:52 -06:00
blk.h block: fix null pointer dereference in blk_mq_rq_timed_out() 2019-10-05 13:10:08 +02:00
bounce.c block: copy ioprio in __bio_clone_fast() and bounce 2018-12-01 09:37:32 +01:00
bsg-lib.c block/bsg-lib: use PTR_ERR_OR_ZERO to simplify the flow path 2018-08-01 09:13:03 -06:00
bsg.c block: bsg: move atomic_t ref_count variable to refcount API 2018-08-27 19:17:02 -06:00
cfq-iosched.c cfq: Suppress compiler warnings about comparisons 2018-08-07 17:57:13 -06:00
cmdline-parser.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compat_ioctl.c compat_ioctl: block: handle BLKREPORTZONE/BLKRESETZONE 2020-01-09 10:19:01 +01:00
deadline-iosched.c block drivers/block: Use octal not symbolic permissions 2018-05-24 13:38:59 -06:00
elevator.c block: fix deadline elevator drain for zoned block devices 2018-09-26 19:57:24 -06:00
genhd.c block: fix use-after-free on gendisk 2019-05-31 06:46:18 -07:00
ioctl.c block: pass inclusive 'lend' parameter to truncate_inode_pages_range 2018-02-23 15:20:19 -07:00
ioprio.c block: add ioprio_check_cap function 2018-05-31 10:50:54 -04:00
Kconfig block: introduce blk-iolatency io controller 2018-07-09 09:07:54 -06:00
Kconfig.iosched License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
kyber-iosched.c block: kyber: make kyber more friendly with merging 2018-05-30 10:47:40 -06:00
Makefile block: introduce blk-iolatency io controller 2018-07-09 09:07:54 -06:00
mq-deadline.c block: mq-deadline: Fix queue restart handling 2019-10-07 18:57:19 +02:00
noop-iosched.c
opal_proto.h block: sed-opal: Set MBRDone on S3 resume path if TPER is MBREnabled 2017-09-11 09:45:52 -06:00
partition-generic.c block: fix use-after-free on gendisk 2019-05-31 06:46:18 -07:00
scsi_ioctl.c block: consistently use GFP_NOIO instead of __GFP_NORECLAIM 2018-05-14 08:55:18 -06:00
sed-opal.c block: sed-opal: fix IOC_OPAL_ENABLE_DISABLE_MBR 2019-05-31 06:46:24 -07:00
t10-pi.c block: move dif_prepare/dif_complete functions to block layer 2018-07-30 08:27:02 -06:00