linux.git/block, branch v5.16-rc2 Linux kernel source tree blk-mq: don't insert FUA request with data into scheduler queue 2021-11-19T13:28:18+00:00 Ming Lei ming.lei@redhat.com 2021-11-18T15:30:41+00:00 2b504bd4841bccbf3eb83c1fec229b65956ad8ad We never insert flush request into scheduler queue before. Recently commit d92ca9d8348f ("blk-mq: don't handle non-flush requests in blk_insert_flush") tries to handle FUA data request as normal request. This way has caused warning[1] in mq-deadline dd_exit_sched() or io hang in case of kyber since RQF_ELVPRIV isn't set for flush request, then ->finish_request won't be called. Fix the issue by inserting FUA data request with blk_mq_request_bypass_insert() when the device supports FUA, just like what we did before. [1] https://lore.kernel.org/linux-block/CAHj4cs-_vkTW=dAzbZYGxpEWSpzpcmaNeY1R=vH311+9vMUSdg@mail.gmail.com/ Reported-by: Yi Zhang <yi.zhang@redhat.com> Fixes: d92ca9d8348f ("blk-mq: don't handle non-flush requests in blk_insert_flush") Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20211118153041.2163228-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> 
We never insert flush request into scheduler queue before.

Recently commit d92ca9d8348f ("blk-mq: don't handle non-flush requests in
blk_insert_flush") tries to handle FUA data request as normal request.
This way has caused warning[1] in mq-deadline dd_exit_sched() or io hang in
case of kyber since RQF_ELVPRIV isn't set for flush request, then
->finish_request won't be called.

Fix the issue by inserting FUA data request with blk_mq_request_bypass_insert()
when the device supports FUA, just like what we did before.

[1] https://lore.kernel.org/linux-block/CAHj4cs-_vkTW=dAzbZYGxpEWSpzpcmaNeY1R=vH311+9vMUSdg@mail.gmail.com/

Reported-by: Yi Zhang <yi.zhang@redhat.com>
Fixes: d92ca9d8348f ("blk-mq: don't handle non-flush requests in blk_insert_flush")
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20211118153041.2163228-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk-cgroup: fix missing put device in error path from blkg_conf_pref() 2021-11-19T13:26:45+00:00 Yu Kuai yukuai3@huawei.com 2021-11-02T02:07:05+00:00 15c30104965101b8e76b24d27035569d6613a7d6 If blk_queue_enter() failed due to queue is dying, the blkdev_put_no_open() is needed because blkcg_conf_open_bdev() succeeded. Fixes: 0c9d338c8443 ("blk-cgroup: synchronize blkg creation against policy deactivation") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20211102020705.2321858-1-yukuai3@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk> 
If blk_queue_enter() failed due to queue is dying, the
blkdev_put_no_open() is needed because blkcg_conf_open_bdev() succeeded.

Fixes: 0c9d338c8443 ("blk-cgroup: synchronize blkg creation against policy deactivation")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20211102020705.2321858-1-yukuai3@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: avoid to quiesce queue in elevator_init_mq 2021-11-17T14:43:26+00:00 Ming Lei ming.lei@redhat.com 2021-11-17T11:55:02+00:00 245a489e81e13dd55ae46d27becf6d5901eb7828 elevator_init_mq() is only called before adding disk, when there isn't any FS I/O, only passthrough requests can be queued, so freezing queue plus canceling dispatch work is enough to drain any dispatch activities, then we can avoid synchronize_srcu() in blk_mq_quiesce_queue(). Long boot latency issue can be fixed in case of lots of disks added during booting. Fixes: 737eb78e82d5 ("block: Delay default elevator initialization") Reported-by: yangerkun <yangerkun@huawei.com> Cc: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20211117115502.1600950-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> 
elevator_init_mq() is only called before adding disk, when there isn't
any FS I/O, only passthrough requests can be queued, so freezing queue
plus canceling dispatch work is enough to drain any dispatch activities,
then we can avoid synchronize_srcu() in blk_mq_quiesce_queue().

Long boot latency issue can be fixed in case of lots of disks added
during booting.

Fixes: 737eb78e82d5 ("block: Delay default elevator initialization")
Reported-by: yangerkun <yangerkun@huawei.com>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20211117115502.1600950-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk-mq: cancel blk-mq dispatch work in both blk_cleanup_queue and disk_release() 2021-11-16T02:22:13+00:00 Ming Lei ming.lei@redhat.com 2021-11-16T01:43:43+00:00 2a19b28f7929866e1cec92a3619f4de9f2d20005 For avoiding to slow down queue destroy, we don't call blk_mq_quiesce_queue() in blk_cleanup_queue(), instead of delaying to cancel dispatch work in blk_release_queue(). However, this way has caused kernel oops[1], reported by Changhui. The log shows that scsi_device can be freed before running blk_release_queue(), which is expected too since scsi_device is released after the scsi disk is closed and the scsi_device is removed. Fixes the issue by canceling blk-mq dispatch work in both blk_cleanup_queue() and disk_release(): 1) when disk_release() is run, the disk has been closed, and any sync dispatch activities have been done, so canceling dispatch work is enough to quiesce filesystem I/O dispatch activity. 2) in blk_cleanup_queue(), we only focus on passthrough request, and passthrough request is always explicitly allocated & freed by its caller, so once queue is frozen, all sync dispatch activity for passthrough request has been done, then it is enough to just cancel dispatch work for avoiding any dispatch activity. [1] kernel panic log [12622.769416] BUG: kernel NULL pointer dereference, address: 0000000000000300 [12622.777186] #PF: supervisor read access in kernel mode [12622.782918] #PF: error_code(0x0000) - not-present page [12622.788649] PGD 0 P4D 0 [12622.791474] Oops: 0000 [#1] PREEMPT SMP PTI [12622.796138] CPU: 10 PID: 744 Comm: kworker/10:1H Kdump: loaded Not tainted 5.15.0+ #1 [12622.804877] Hardware name: Dell Inc. PowerEdge R730/0H21J3, BIOS 1.5.4 10/002/2015 [12622.813321] Workqueue: kblockd blk_mq_run_work_fn [12622.818572] RIP: 0010:sbitmap_get+0x75/0x190 [12622.823336] Code: 85 80 00 00 00 41 8b 57 08 85 d2 0f 84 b1 00 00 00 45 31 e4 48 63 cd 48 8d 1c 49 48 c1 e3 06 49 03 5f 10 4c 8d 6b 40 83 f0 01 <48> 8b 33 44 89 f2 4c 89 ef 0f b6 c8 e8 fa f3 ff ff 83 f8 ff 75 58 [12622.844290] RSP: 0018:ffffb00a446dbd40 EFLAGS: 00010202 [12622.850120] RAX: 0000000000000001 RBX: 0000000000000300 RCX: 0000000000000004 [12622.858082] RDX: 0000000000000006 RSI: 0000000000000082 RDI: ffffa0b7a2dfe030 [12622.866042] RBP: 0000000000000004 R08: 0000000000000001 R09: ffffa0b742721334 [12622.874003] R10: 0000000000000008 R11: 0000000000000008 R12: 0000000000000000 [12622.881964] R13: 0000000000000340 R14: 0000000000000000 R15: ffffa0b7a2dfe030 [12622.889926] FS: 0000000000000000(0000) GS:ffffa0baafb40000(0000) knlGS:0000000000000000 [12622.898956] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [12622.905367] CR2: 0000000000000300 CR3: 0000000641210001 CR4: 00000000001706e0 [12622.913328] Call Trace: [12622.916055] <TASK> [12622.918394] scsi_mq_get_budget+0x1a/0x110 [12622.922969] __blk_mq_do_dispatch_sched+0x1d4/0x320 [12622.928404] ? pick_next_task_fair+0x39/0x390 [12622.933268] __blk_mq_sched_dispatch_requests+0xf4/0x140 [12622.939194] blk_mq_sched_dispatch_requests+0x30/0x60 [12622.944829] __blk_mq_run_hw_queue+0x30/0xa0 [12622.949593] process_one_work+0x1e8/0x3c0 [12622.954059] worker_thread+0x50/0x3b0 [12622.958144] ? rescuer_thread+0x370/0x370 [12622.962616] kthread+0x158/0x180 [12622.966218] ? set_kthread_struct+0x40/0x40 [12622.970884] ret_from_fork+0x22/0x30 [12622.974875] </TASK> [12622.977309] Modules linked in: scsi_debug rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs sunrpc dm_multipath intel_rapl_msr intel_rapl_common dell_wmi_descriptor sb_edac rfkill video x86_pkg_temp_thermal intel_powerclamp dcdbas coretemp kvm_intel kvm mgag200 irqbypass i2c_algo_bit rapl drm_kms_helper ipmi_ssif intel_cstate intel_uncore syscopyarea sysfillrect sysimgblt fb_sys_fops pcspkr cec mei_me lpc_ich mei ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter drm fuse xfs libcrc32c sr_mod cdrom sd_mod t10_pi sg ixgbe ahci libahci crct10dif_pclmul crc32_pclmul crc32c_intel libata megaraid_sas ghash_clmulni_intel tg3 wdat_wdt mdio dca wmi dm_mirror dm_region_hash dm_log dm_mod [last unloaded: scsi_debug] Reported-by: ChanghuiZhong <czhong@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: linux-scsi@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20211116014343.610501-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> 
For avoiding to slow down queue destroy, we don't call
blk_mq_quiesce_queue() in blk_cleanup_queue(), instead of delaying to
cancel dispatch work in blk_release_queue().

However, this way has caused kernel oops[1], reported by Changhui. The log
shows that scsi_device can be freed before running blk_release_queue(),
which is expected too since scsi_device is released after the scsi disk
is closed and the scsi_device is removed.

Fixes the issue by canceling blk-mq dispatch work in both blk_cleanup_queue()
and disk_release():

1) when disk_release() is run, the disk has been closed, and any sync
dispatch activities have been done, so canceling dispatch work is enough to
quiesce filesystem I/O dispatch activity.

2) in blk_cleanup_queue(), we only focus on passthrough request, and
passthrough request is always explicitly allocated & freed by
its caller, so once queue is frozen, all sync dispatch activity
for passthrough request has been done, then it is enough to just cancel
dispatch work for avoiding any dispatch activity.

[1] kernel panic log
[12622.769416] BUG: kernel NULL pointer dereference, address: 0000000000000300
[12622.777186] #PF: supervisor read access in kernel mode
[12622.782918] #PF: error_code(0x0000) - not-present page
[12622.788649] PGD 0 P4D 0
[12622.791474] Oops: 0000 [#1] PREEMPT SMP PTI
[12622.796138] CPU: 10 PID: 744 Comm: kworker/10:1H Kdump: loaded Not tainted 5.15.0+ #1
[12622.804877] Hardware name: Dell Inc. PowerEdge R730/0H21J3, BIOS 1.5.4 10/002/2015
[12622.813321] Workqueue: kblockd blk_mq_run_work_fn
[12622.818572] RIP: 0010:sbitmap_get+0x75/0x190
[12622.823336] Code: 85 80 00 00 00 41 8b 57 08 85 d2 0f 84 b1 00 00 00 45 31 e4 48 63 cd 48 8d 1c 49 48 c1 e3 06 49 03 5f 10 4c 8d 6b 40 83 f0 01 <48> 8b 33 44 89 f2 4c 89 ef 0f b6 c8 e8 fa f3 ff ff 83 f8 ff 75 58
[12622.844290] RSP: 0018:ffffb00a446dbd40 EFLAGS: 00010202
[12622.850120] RAX: 0000000000000001 RBX: 0000000000000300 RCX: 0000000000000004
[12622.858082] RDX: 0000000000000006 RSI: 0000000000000082 RDI: ffffa0b7a2dfe030
[12622.866042] RBP: 0000000000000004 R08: 0000000000000001 R09: ffffa0b742721334
[12622.874003] R10: 0000000000000008 R11: 0000000000000008 R12: 0000000000000000
[12622.881964] R13: 0000000000000340 R14: 0000000000000000 R15: ffffa0b7a2dfe030
[12622.889926] FS:  0000000000000000(0000) GS:ffffa0baafb40000(0000) knlGS:0000000000000000
[12622.898956] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[12622.905367] CR2: 0000000000000300 CR3: 0000000641210001 CR4: 00000000001706e0
[12622.913328] Call Trace:
[12622.916055]  <TASK>
[12622.918394]  scsi_mq_get_budget+0x1a/0x110
[12622.922969]  __blk_mq_do_dispatch_sched+0x1d4/0x320
[12622.928404]  ? pick_next_task_fair+0x39/0x390
[12622.933268]  __blk_mq_sched_dispatch_requests+0xf4/0x140
[12622.939194]  blk_mq_sched_dispatch_requests+0x30/0x60
[12622.944829]  __blk_mq_run_hw_queue+0x30/0xa0
[12622.949593]  process_one_work+0x1e8/0x3c0
[12622.954059]  worker_thread+0x50/0x3b0
[12622.958144]  ? rescuer_thread+0x370/0x370
[12622.962616]  kthread+0x158/0x180
[12622.966218]  ? set_kthread_struct+0x40/0x40
[12622.970884]  ret_from_fork+0x22/0x30
[12622.974875]  </TASK>
[12622.977309] Modules linked in: scsi_debug rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs sunrpc dm_multipath intel_rapl_msr intel_rapl_common dell_wmi_descriptor sb_edac rfkill video x86_pkg_temp_thermal intel_powerclamp dcdbas coretemp kvm_intel kvm mgag200 irqbypass i2c_algo_bit rapl drm_kms_helper ipmi_ssif intel_cstate intel_uncore syscopyarea sysfillrect sysimgblt fb_sys_fops pcspkr cec mei_me lpc_ich mei ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter drm fuse xfs libcrc32c sr_mod cdrom sd_mod t10_pi sg ixgbe ahci libahci crct10dif_pclmul crc32_pclmul crc32c_intel libata megaraid_sas ghash_clmulni_intel tg3 wdat_wdt mdio dca wmi dm_mirror dm_region_hash dm_log dm_mod [last unloaded: scsi_debug]

Reported-by: ChanghuiZhong <czhong@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20211116014343.610501-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: fix missing queue put in error path 2021-11-16T00:00:54+00:00 Jens Axboe axboe@kernel.dk 2021-11-15T21:23:08+00:00 95febeb61bf87ca803a1270498cd4cd61554a68f If we fail the submission queue checks, we don't put the queue afterwards. This can cause various issues like stalls on scheduler switch or failure to remove the device, or like in the original bug report, timeout waiting for the device on reboot/restart. While in there, fix a few whitespace discrepancies in the surrounding code. Link: https://bugzilla.kernel.org/show_bug.cgi?id=215039 Fixes: b637108a4022 ("blk-mq: fix filesystem I/O request allocation") Reported-and-tested-by: Stephen Smith <stephenmsmith@blueyonder.co.uk> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> 
If we fail the submission queue checks, we don't put the queue afterwards.
This can cause various issues like stalls on scheduler switch or failure
to remove the device, or like in the original bug report, timeout waiting
for the device on reboot/restart.

While in there, fix a few whitespace discrepancies in the surrounding
code.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215039
Fixes: b637108a4022 ("blk-mq: fix filesystem I/O request allocation")
Reported-and-tested-by: Stephen Smith <stephenmsmith@blueyonder.co.uk>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: Check ADMIN before NICE for IOPRIO_CLASS_RT 2021-11-15T21:28:59+00:00 Alistair Delva adelva@google.com 2021-11-15T18:16:55+00:00 94c4b4fd25e6c3763941bdec3ad54f2204afa992 Booting to Android userspace on 5.14 or newer triggers the following SELinux denial: avc: denied { sys_nice } for comm="init" capability=23 scontext=u:r:init:s0 tcontext=u:r:init:s0 tclass=capability permissive=0 Init is PID 0 running as root, so it already has CAP_SYS_ADMIN. For better compatibility with older SEPolicy, check ADMIN before NICE. Fixes: 9d3a39a5f1e4 ("block: grant IOPRIO_CLASS_RT to CAP_SYS_NICE") Signed-off-by: Alistair Delva <adelva@google.com> Cc: Khazhismel Kumykov <khazhy@google.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Serge Hallyn <serge@hallyn.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Paul Moore <paul@paul-moore.com> Cc: selinux@vger.kernel.org Cc: linux-security-module@vger.kernel.org Cc: kernel-team@android.com Cc: stable@vger.kernel.org # v5.14+ Reviewed-by: Bart Van Assche <bvanassche@acm.org> Acked-by: Serge Hallyn <serge@hallyn.com> Link: https://lore.kernel.org/r/20211115181655.3608659-1-adelva@google.com Signed-off-by: Jens Axboe <axboe@kernel.dk> 
Booting to Android userspace on 5.14 or newer triggers the following
SELinux denial:

avc: denied { sys_nice } for comm="init" capability=23
     scontext=u:r:init:s0 tcontext=u:r:init:s0 tclass=capability
     permissive=0

Init is PID 0 running as root, so it already has CAP_SYS_ADMIN. For
better compatibility with older SEPolicy, check ADMIN before NICE.

Fixes: 9d3a39a5f1e4 ("block: grant IOPRIO_CLASS_RT to CAP_SYS_NICE")
Signed-off-by: Alistair Delva <adelva@google.com>
Cc: Khazhismel Kumykov <khazhy@google.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: selinux@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: kernel-team@android.com
Cc: stable@vger.kernel.org # v5.14+
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Serge Hallyn <serge@hallyn.com>
Link: https://lore.kernel.org/r/20211115181655.3608659-1-adelva@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk-mq: fix filesystem I/O request allocation 2021-11-12T16:31:13+00:00 Ming Lei ming.lei@redhat.com 2021-11-12T12:47:15+00:00 b637108a4022951dcc71b672bd101ebe24ad26d5 submit_bio_checks() may update bio->bi_opf, so we have to initialize blk_mq_alloc_data.cmd_flags with bio->bi_opf after submit_bio_checks() returns when allocating new request. In case of using cached request, fallback to allocate new request if cached rq isn't compatible with the incoming bio, otherwise change rq->cmd_flags with incoming bio->bi_opf. Fixes: 900e080752025f00 ("block: move queue enter logic into blk_mq_submit_bio()") Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> 
submit_bio_checks() may update bio->bi_opf, so we have to initialize
blk_mq_alloc_data.cmd_flags with bio->bi_opf after submit_bio_checks()
returns when allocating new request.

In case of using cached request, fallback to allocate new request if
cached rq isn't compatible with the incoming bio, otherwise change
rq->cmd_flags with incoming bio->bi_opf.

Fixes: 900e080752025f00 ("block: move queue enter logic into blk_mq_submit_bio()")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blkcg: Remove extra blkcg_bio_issue_init 2021-11-12T12:46:07+00:00 Laibin Qiu qiulaibin@huawei.com 2021-11-12T09:33:54+00:00 b781d8db580c058ecd54ed7d5dde7f8270b25f5b KASAN reports a use-after-free report when doing block test: ================================================================== [10050.967049] BUG: KASAN: use-after-free in submit_bio_checks+0x1539/0x1550 [10050.977638] Call Trace: [10050.978190] dump_stack+0x9b/0xce [10050.979674] print_address_description.constprop.6+0x3e/0x60 [10050.983510] kasan_report.cold.9+0x22/0x3a [10050.986089] submit_bio_checks+0x1539/0x1550 [10050.989576] submit_bio_noacct+0x83/0xc80 [10050.993714] submit_bio+0xa7/0x330 [10050.994435] mpage_readahead+0x380/0x500 [10050.998009] read_pages+0x1c1/0xbf0 [10051.002057] page_cache_ra_unbounded+0x4c2/0x6f0 [10051.007413] do_page_cache_ra+0xda/0x110 [10051.008207] force_page_cache_ra+0x23d/0x3d0 [10051.009087] page_cache_sync_ra+0xca/0x300 [10051.009970] generic_file_buffered_read+0xbea/0x2130 [10051.012685] generic_file_read_iter+0x315/0x490 [10051.014472] blkdev_read_iter+0x113/0x1b0 [10051.015300] aio_read+0x2ad/0x450 [10051.023786] io_submit_one+0xc8e/0x1d60 [10051.029855] __se_sys_io_submit+0x125/0x350 [10051.033442] do_syscall_64+0x2d/0x40 [10051.034156] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [10051.048733] Allocated by task 18598: [10051.049482] kasan_save_stack+0x19/0x40 [10051.050263] __kasan_kmalloc.constprop.1+0xc1/0xd0 [10051.051230] kmem_cache_alloc+0x146/0x440 [10051.052060] mempool_alloc+0x125/0x2f0 [10051.052818] bio_alloc_bioset+0x353/0x590 [10051.053658] mpage_alloc+0x3b/0x240 [10051.054382] do_mpage_readpage+0xddf/0x1ef0 [10051.055250] mpage_readahead+0x264/0x500 [10051.056060] read_pages+0x1c1/0xbf0 [10051.056758] page_cache_ra_unbounded+0x4c2/0x6f0 [10051.057702] do_page_cache_ra+0xda/0x110 [10051.058511] force_page_cache_ra+0x23d/0x3d0 [10051.059373] page_cache_sync_ra+0xca/0x300 [10051.060198] generic_file_buffered_read+0xbea/0x2130 [10051.061195] generic_file_read_iter+0x315/0x490 [10051.062189] blkdev_read_iter+0x113/0x1b0 [10051.063015] aio_read+0x2ad/0x450 [10051.063686] io_submit_one+0xc8e/0x1d60 [10051.064467] __se_sys_io_submit+0x125/0x350 [10051.065318] do_syscall_64+0x2d/0x40 [10051.066082] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [10051.067455] Freed by task 13307: [10051.068136] kasan_save_stack+0x19/0x40 [10051.068931] kasan_set_track+0x1c/0x30 [10051.069726] kasan_set_free_info+0x1b/0x30 [10051.070621] __kasan_slab_free+0x111/0x160 [10051.071480] kmem_cache_free+0x94/0x460 [10051.072256] mempool_free+0xd6/0x320 [10051.072985] bio_free+0xe0/0x130 [10051.073630] bio_put+0xab/0xe0 [10051.074252] bio_endio+0x3a6/0x5d0 [10051.074984] blk_update_request+0x590/0x1370 [10051.075870] scsi_end_request+0x7d/0x400 [10051.076667] scsi_io_completion+0x1aa/0xe50 [10051.077503] scsi_softirq_done+0x11b/0x240 [10051.078344] blk_mq_complete_request+0xd4/0x120 [10051.079275] scsi_mq_done+0xf0/0x200 [10051.080036] virtscsi_vq_done+0xbc/0x150 [10051.080850] vring_interrupt+0x179/0x390 [10051.081650] __handle_irq_event_percpu+0xf7/0x490 [10051.082626] handle_irq_event_percpu+0x7b/0x160 [10051.083527] handle_irq_event+0xcc/0x170 [10051.084297] handle_edge_irq+0x215/0xb20 [10051.085122] asm_call_irq_on_stack+0xf/0x20 [10051.085986] common_interrupt+0xae/0x120 [10051.086830] asm_common_interrupt+0x1e/0x40 ================================================================== Bio will be checked at beginning of submit_bio_noacct(). If bio needs to be throttled, it will start the timer and stop submit bio directly. Bio will submit in blk_throtl_dispatch_work_fn() when the timer expires. But in the current process, if bio is throttled, it will still set bio issue->value by blkcg_bio_issue_init(). This is redundant and may cause the above use-after-free. CPU0 CPU1 submit_bio submit_bio_noacct submit_bio_checks blk_throtl_bio() <=mod_timer(&sq->pending_timer blk_throtl_dispatch_work_fn submit_bio_noacct() <= bio have throttle tag, will throw directly and bio issue->value will be set here bio_endio() bio_put() bio_free() <= free this bio blkcg_bio_issue_init(bio) <= bio has been freed and will lead to UAF return BLK_QC_T_NONE Fix this by remove extra blkcg_bio_issue_init. Fixes: e439bedf6b24 (blkcg: consolidate bio_issue_init() to be a part of core) Signed-off-by: Laibin Qiu <qiulaibin@huawei.com> Link: https://lore.kernel.org/r/20211112093354.3581504-1-qiulaibin@huawei.com Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> 
KASAN reports a use-after-free report when doing block test:

==================================================================
[10050.967049] BUG: KASAN: use-after-free in
submit_bio_checks+0x1539/0x1550

[10050.977638] Call Trace:
[10050.978190]  dump_stack+0x9b/0xce
[10050.979674]  print_address_description.constprop.6+0x3e/0x60
[10050.983510]  kasan_report.cold.9+0x22/0x3a
[10050.986089]  submit_bio_checks+0x1539/0x1550
[10050.989576]  submit_bio_noacct+0x83/0xc80
[10050.993714]  submit_bio+0xa7/0x330
[10050.994435]  mpage_readahead+0x380/0x500
[10050.998009]  read_pages+0x1c1/0xbf0
[10051.002057]  page_cache_ra_unbounded+0x4c2/0x6f0
[10051.007413]  do_page_cache_ra+0xda/0x110
[10051.008207]  force_page_cache_ra+0x23d/0x3d0
[10051.009087]  page_cache_sync_ra+0xca/0x300
[10051.009970]  generic_file_buffered_read+0xbea/0x2130
[10051.012685]  generic_file_read_iter+0x315/0x490
[10051.014472]  blkdev_read_iter+0x113/0x1b0
[10051.015300]  aio_read+0x2ad/0x450
[10051.023786]  io_submit_one+0xc8e/0x1d60
[10051.029855]  __se_sys_io_submit+0x125/0x350
[10051.033442]  do_syscall_64+0x2d/0x40
[10051.034156]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[10051.048733] Allocated by task 18598:
[10051.049482]  kasan_save_stack+0x19/0x40
[10051.050263]  __kasan_kmalloc.constprop.1+0xc1/0xd0
[10051.051230]  kmem_cache_alloc+0x146/0x440
[10051.052060]  mempool_alloc+0x125/0x2f0
[10051.052818]  bio_alloc_bioset+0x353/0x590
[10051.053658]  mpage_alloc+0x3b/0x240
[10051.054382]  do_mpage_readpage+0xddf/0x1ef0
[10051.055250]  mpage_readahead+0x264/0x500
[10051.056060]  read_pages+0x1c1/0xbf0
[10051.056758]  page_cache_ra_unbounded+0x4c2/0x6f0
[10051.057702]  do_page_cache_ra+0xda/0x110
[10051.058511]  force_page_cache_ra+0x23d/0x3d0
[10051.059373]  page_cache_sync_ra+0xca/0x300
[10051.060198]  generic_file_buffered_read+0xbea/0x2130
[10051.061195]  generic_file_read_iter+0x315/0x490
[10051.062189]  blkdev_read_iter+0x113/0x1b0
[10051.063015]  aio_read+0x2ad/0x450
[10051.063686]  io_submit_one+0xc8e/0x1d60
[10051.064467]  __se_sys_io_submit+0x125/0x350
[10051.065318]  do_syscall_64+0x2d/0x40
[10051.066082]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[10051.067455] Freed by task 13307:
[10051.068136]  kasan_save_stack+0x19/0x40
[10051.068931]  kasan_set_track+0x1c/0x30
[10051.069726]  kasan_set_free_info+0x1b/0x30
[10051.070621]  __kasan_slab_free+0x111/0x160
[10051.071480]  kmem_cache_free+0x94/0x460
[10051.072256]  mempool_free+0xd6/0x320
[10051.072985]  bio_free+0xe0/0x130
[10051.073630]  bio_put+0xab/0xe0
[10051.074252]  bio_endio+0x3a6/0x5d0
[10051.074984]  blk_update_request+0x590/0x1370
[10051.075870]  scsi_end_request+0x7d/0x400
[10051.076667]  scsi_io_completion+0x1aa/0xe50
[10051.077503]  scsi_softirq_done+0x11b/0x240
[10051.078344]  blk_mq_complete_request+0xd4/0x120
[10051.079275]  scsi_mq_done+0xf0/0x200
[10051.080036]  virtscsi_vq_done+0xbc/0x150
[10051.080850]  vring_interrupt+0x179/0x390
[10051.081650]  __handle_irq_event_percpu+0xf7/0x490
[10051.082626]  handle_irq_event_percpu+0x7b/0x160
[10051.083527]  handle_irq_event+0xcc/0x170
[10051.084297]  handle_edge_irq+0x215/0xb20
[10051.085122]  asm_call_irq_on_stack+0xf/0x20
[10051.085986]  common_interrupt+0xae/0x120
[10051.086830]  asm_common_interrupt+0x1e/0x40

==================================================================

Bio will be checked at beginning of submit_bio_noacct(). If bio needs
to be throttled, it will start the timer and stop submit bio directly.
Bio will submit in blk_throtl_dispatch_work_fn() when the timer expires.
But in the current process, if bio is throttled, it will still set bio
issue->value by blkcg_bio_issue_init(). This is redundant and may cause
the above use-after-free.

CPU0                                   CPU1
submit_bio
submit_bio_noacct
  submit_bio_checks
    blk_throtl_bio()
      <=mod_timer(&sq->pending_timer
                                      blk_throtl_dispatch_work_fn
                                        submit_bio_noacct() <= bio have
                                        throttle tag, will throw directly
                                        and bio issue->value will be set
                                        here

                                      bio_endio()
                                      bio_put()
                                      bio_free() <= free this bio

    blkcg_bio_issue_init(bio)
      <= bio has been freed and
      will lead to UAF
  return BLK_QC_T_NONE

Fix this by remove extra blkcg_bio_issue_init.

Fixes: e439bedf6b24 (blkcg: consolidate bio_issue_init() to be a part of core)
Signed-off-by: Laibin Qiu <qiulaibin@huawei.com>
Link: https://lore.kernel.org/r/20211112093354.3581504-1-qiulaibin@huawei.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: Hold invalidate_lock in BLKRESETZONE ioctl 2021-11-11T18:52:46+00:00 Shin'ichiro Kawasaki shinichiro.kawasaki@wdc.com 2021-11-11T08:52:38+00:00 86399ea071099ec8ee0a83ac9ad67f7df96a50ad When BLKRESETZONE ioctl and data read race, the data read leaves stale page cache. The commit e5113505904e ("block: Discard page cache of zone reset target range") added page cache truncation to avoid stale page cache after the ioctl. However, the stale page cache still can be read during the reset zone operation for the ioctl. To avoid the stale page cache completely, hold invalidate_lock of the block device file mapping. Fixes: e5113505904e ("block: Discard page cache of zone reset target range") Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Cc: stable@vger.kernel.org # v5.15 Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20211111085238.942492-1-shinichiro.kawasaki@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk> 
When BLKRESETZONE ioctl and data read race, the data read leaves stale
page cache. The commit e5113505904e ("block: Discard page cache of zone
reset target range") added page cache truncation to avoid stale page
cache after the ioctl. However, the stale page cache still can be read
during the reset zone operation for the ioctl. To avoid the stale page
cache completely, hold invalidate_lock of the block device file mapping.

Fixes: e5113505904e ("block: Discard page cache of zone reset target range")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.15
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20211111085238.942492-1-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk-mq: rename blk_attempt_bio_merge 2021-11-11T18:52:33+00:00 Ming Lei ming.lei@redhat.com 2021-11-11T08:51:34+00:00 b131f2011115f3c18a49e17762486501496fea3c It is very annoying to have two block layer functions which share same name, so rename blk_attempt_bio_merge in blk-mq.c as blk_mq_attempt_bio_merge. Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211111085134.345235-3-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> 
It is very annoying to have two block layer functions which share same
name, so rename blk_attempt_bio_merge in blk-mq.c as
blk_mq_attempt_bio_merge.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211111085134.345235-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>