linux-stable.git/block, branch v4.14.166

block: fix memleak when __blk_rq_map_user_iov() is failed

2020-01-12T11:12:00+00:00

[ Upstream commit 3b7995a98ad76da5597b488fa84aa5a56d43b608 ]

When I doing fuzzy test, get the memleak report:

BUG: memory leak
unreferenced object 0xffff88837af80000 (size 4096):
  comm "memleak", pid 3557, jiffies 4294817681 (age 112.499s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    20 00 00 00 10 01 00 00 00 00 00 00 01 00 00 00   ...............
  backtrace:
    [<000000001c894df8>] bio_alloc_bioset+0x393/0x590
    [<000000008b139a3c>] bio_copy_user_iov+0x300/0xcd0
    [<00000000a998bd8c>] blk_rq_map_user_iov+0x2f1/0x5f0
    [<000000005ceb7f05>] blk_rq_map_user+0xf2/0x160
    [<000000006454da92>] sg_common_write.isra.21+0x1094/0x1870
    [<00000000064bb208>] sg_write.part.25+0x5d9/0x950
    [<000000004fc670f6>] sg_write+0x5f/0x8c
    [<00000000b0d05c7b>] __vfs_write+0x7c/0x100
    [<000000008e177714>] vfs_write+0x1c3/0x500
    [<0000000087d23f34>] ksys_write+0xf9/0x200
    [<000000002c8dbc9d>] do_syscall_64+0x9f/0x4f0
    [<00000000678d8e9a>] entry_SYSCALL_64_after_hwframe+0x49/0xbe

If __blk_rq_map_user_iov() is failed in blk_rq_map_user_iov(),
the bio(s) which is allocated before this failing will leak. The
refcount of the bio(s) is init to 1 and increased to 2 by calling
bio_get(), but __blk_rq_unmap_user() only decrease it to 1, so
the bio cannot be freed. Fix it by calling blk_rq_unmap_user().

Reviewed-by: Bob Liu 
Reported-by: Hulk Robot 
Signed-off-by: Yang Yingliang 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

compat_ioctl: block: handle BLKREPORTZONE/BLKRESETZONE

2020-01-09T09:17:55+00:00

commit 673bdf8ce0a387ef585c13b69a2676096c6edfe9 upstream.

These were added to blkdev_ioctl() but not blkdev_compat_ioctl,
so add them now.

Cc:  # v4.10+
Fixes: 3ed05a987e0f ("blk-zoned: implement ioctls")
Reviewed-by: Damien Le Moal 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

compat_ioctl: block: handle Persistent Reservations

2020-01-09T09:17:55+00:00

commit b2c0fcd28772f99236d261509bcd242135677965 upstream.

These were added to blkdev_ioctl() in linux-5.5 but not
blkdev_compat_ioctl, so add them now.

Cc:  # v4.4+
Fixes: bbd3e064362e ("block: add an API for Persistent Reservations")
Signed-off-by: Arnd Bergmann 
Signed-off-by: Greg Kroah-Hartman 

Fold in followup patch from Arnd with missing pr.h header include.

Signed-off-by: Jens Axboe

blk-mq: make sure that line break can be printed

2019-12-17T19:39:59+00:00

commit d2c9be89f8ebe7ebcc97676ac40f8dec1cf9b43a upstream.

8962842ca5ab ("blk-mq: avoid sysfs buffer overflow with too many CPU cores")
avoids sysfs buffer overflow, and reserves one character for line break.
However, the last snprintf() doesn't get correct 'size' parameter passed
in, so fixed it.

Fixes: 8962842ca5ab ("blk-mq: avoid sysfs buffer overflow with too many CPU cores")
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe 
Cc: Nobuhiro Iwamatsu 
Signed-off-by: Greg Kroah-Hartman

block: fix single range discard merge

2019-12-17T19:39:46+00:00

commit 2a5cf35cd6c56b2924bce103413ad3381bdc31fa upstream.

There are actually two kinds of discard merge:

- one is the normal discard merge, just like normal read/write request,
and call it single-range discard

- another is the multi-range discard, queue_max_discard_segments(rq->q) > 1

For the former case, queue_max_discard_segments(rq->q) is 1, and we
should handle this kind of discard merge like the normal read/write
request.

This patch fixes the following kernel panic issue[1], which is caused by
not removing the single-range discard request from elevator queue.

Guangwu has one raid discard test case, in which this issue is a bit
easier to trigger, and I verified that this patch can fix the kernel
panic issue in Guangwu's test case.

[1] kernel panic log from Jens's report

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000148
 PGD 0 P4D 0.
 Oops: 0000 [#1] SMP PTI
 CPU: 37 PID: 763 Comm: kworker/37:1H Not tainted \
4.20.0-rc3-00649-ge64d9a554a91-dirty #14  Hardware name: Wiwynn \
Leopard-Orv2/Leopard-DDR BW, BIOS LBM08   03/03/2017       Workqueue: kblockd \
blk_mq_run_work_fn                                            RIP: \
0010:blk_mq_get_driver_tag+0x81/0x120                                       Code: 24 \
10 48 89 7c 24 20 74 21 83 fa ff 0f 95 c0 48 8b 4c 24 28 65 48 33 0c 25 28 00 00 00 \
0f 85 96 00 00 00 48 83 c4 30 5b 5d c3 <48> 8b 87 48 01 00 00 8b 40 04 39 43 20 72 37 \
f6 87 b0 00 00 00 02  RSP: 0018:ffffc90004aabd30 EFLAGS: 00010246                     \
  RAX: 0000000000000003 RBX: ffff888465ea1300 RCX: ffffc90004aabde8
 RDX: 00000000ffffffff RSI: ffffc90004aabde8 RDI: 0000000000000000
 RBP: 0000000000000000 R08: ffff888465ea1348 R09: 0000000000000000
 R10: 0000000000001000 R11: 00000000ffffffff R12: ffff888465ea1300
 R13: 0000000000000000 R14: ffff888465ea1348 R15: ffff888465d10000
 FS:  0000000000000000(0000) GS:ffff88846f9c0000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000148 CR3: 000000000220a003 CR4: 00000000003606e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  blk_mq_dispatch_rq_list+0xec/0x480
  ? elv_rb_del+0x11/0x30
  blk_mq_do_dispatch_sched+0x6e/0xf0
  blk_mq_sched_dispatch_requests+0xfa/0x170
  __blk_mq_run_hw_queue+0x5f/0xe0
  process_one_work+0x154/0x350
  worker_thread+0x46/0x3c0
  kthread+0xf5/0x130
  ? process_one_work+0x350/0x350
  ? kthread_destroy_worker+0x50/0x50
  ret_from_fork+0x1f/0x30
 Modules linked in: sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel \
kvm switchtec irqbypass iTCO_wdt iTCO_vendor_support efivars cdc_ether usbnet mii \
cdc_acm i2c_i801 lpc_ich mfd_core ipmi_si ipmi_devintf ipmi_msghandler acpi_cpufreq \
button sch_fq_codel nfsd nfs_acl lockd grace auth_rpcgss oid_registry sunrpc nvme \
nvme_core fuse sg loop efivarfs autofs4  CR2: 0000000000000148                        \

 ---[ end trace 340a1fb996df1b9b ]---
 RIP: 0010:blk_mq_get_driver_tag+0x81/0x120
 Code: 24 10 48 89 7c 24 20 74 21 83 fa ff 0f 95 c0 48 8b 4c 24 28 65 48 33 0c 25 28 \
00 00 00 0f 85 96 00 00 00 48 83 c4 30 5b 5d c3 <48> 8b 87 48 01 00 00 8b 40 04 39 43 \
20 72 37 f6 87 b0 00 00 00 02

Fixes: 445251d0f4d329a ("blk-mq: fix discard merge with scheduler attached")
Reported-by: Jens Axboe 
Cc: Guangwu Zhang 
Cc: Christoph Hellwig 
Cc: Jianchao Wang 
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe 
Cc: Andre Tomt 
Cc: Jack Wang 
Signed-off-by: Greg Kroah-Hartman

blk-mq: avoid sysfs buffer overflow with too many CPU cores

2019-12-17T19:39:28+00:00

commit 8962842ca5abdcf98e22ab3b2b45a103f0408b95 upstream.

It is reported that sysfs buffer overflow can be triggered if the system
has too many CPU cores(>841 on 4K PAGE_SIZE) when showing CPUs of
hctx via /sys/block/$DEV/mq/$N/cpu_list.

Use snprintf to avoid the potential buffer overflow.

This version doesn't change the attribute format, and simply stops
showing CPU numbers if the buffer is going to overflow.

Cc: stable@vger.kernel.org
Fixes: 676141e48af7("blk-mq: don't dump CPU -> hw queue map on driver load")
Signed-off-by: Ming Lei 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

block: fix the DISCARD request merge

2019-12-01T08:13:49+00:00

[ Upstream commit 69840466086d2248898020a08dda52732686c4e6 ]

There are two cases when handle DISCARD merge.
If max_discard_segments == 1, the bios/requests need to be contiguous
to merge. If max_discard_segments > 1, it takes every bio as a range
and different range needn't to be contiguous.

But now, attempt_merge screws this up. It always consider contiguity
for DISCARD for the case max_discard_segments > 1 and cannot merge
contiguous DISCARD for the case max_discard_segments == 1, because
rq_attempt_discard_merge always returns false in this case.
This patch fixes both of the two cases above.

Reviewed-by: Christoph Hellwig 
Reviewed-by: Ming Lei 
Signed-off-by: Jianchao Wang 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

blok, bfq: do not plug I/O if all queues are weight-raised

2019-11-20T17:00:00+00:00

[ Upstream commit c8765de0adfcaaf4ffb2d951e07444f00ffa9453 ]

To reduce latency for interactive and soft real-time applications, bfq
privileges the bfq_queues containing the I/O of these
applications. These privileged queues, referred-to as weight-raised
queues, get a much higher share of the device throughput
w.r.t. non-privileged queues. To preserve this higher share, the I/O
of any non-weight-raised queue must be plugged whenever a sync
weight-raised queue, while being served, remains temporarily empty. To
attain this goal, bfq simply plugs any I/O (from any queue), if a sync
weight-raised queue remains empty while in service.

Unfortunately, this plugging typically lowers throughput with random
I/O, on devices with internal queueing (because it reduces the filling
level of the internal queues of the device).

This commit addresses this issue by restricting the cases where
plugging is performed: if a sync weight-raised queue remains empty
while in service, then I/O plugging is performed only if some of the
active bfq_queues are *not* weight-raised (which is actually the only
circumstance where plugging is needed to preserve the higher share of
the throughput of weight-raised queues). This restriction proved able
to boost throughput in really many use cases needing only maximum
throughput.

Signed-off-by: Paolo Valente 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

blk-mq: move cancel of requeue_work to the front of blk_exit_queue

2019-10-05T10:47:37+00:00

[ Upstream commit e26cc08265dda37d2acc8394604f220ef412299d ]

blk_exit_queue will free elevator_data, while blk_mq_requeue_work
will access it. Move cancel of requeue_work to the front of
blk_exit_queue to avoid use-after-free.

blk_exit_queue                blk_mq_requeue_work
  __elevator_exit               blk_mq_run_hw_queues
    blk_mq_exit_sched             blk_mq_run_hw_queue
      dd_exit_queue                 blk_mq_hctx_has_pending
        kfree(elevator_data)          blk_mq_sched_has_work
                                        dd_has_work

Fixes: fbc2a15e3433 ("blk-mq: move cancel of requeue_work into blk_mq_release")
Cc: stable@vger.kernel.org
Reviewed-by: Ming Lei 
Signed-off-by: zhengbin 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

block/bio-integrity: fix a memory leak bug

2019-07-31T05:28:55+00:00

[ Upstream commit e7bf90e5afe3aa1d1282c1635a49e17a32c4ecec ]

In bio_integrity_prep(), a kernel buffer is allocated through kmalloc() to
hold integrity metadata. Later on, the buffer will be attached to the bio
structure through bio_integrity_add_page(), which returns the number of
bytes of integrity metadata attached. Due to unexpected situations,
bio_integrity_add_page() may return 0. As a result, bio_integrity_prep()
needs to be terminated with 'false' returned to indicate this error.
However, the allocated kernel buffer is not freed on this execution path,
leading to a memory leak.

To fix this issue, free the allocated buffer before returning from
bio_integrity_prep().

Reviewed-by: Ming Lei 
Acked-by: Martin K. Petersen 
Signed-off-by: Wenwen Wang 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin