Commit Graph

6921 Commits

Author SHA1 Message Date
SeongJae Park
186cb020bd xen-blkfront: Cache feature_persistent value before advertisement
commit fe8f65b018 upstream.

Xen blkfront advertises its support of the persistent grants feature
when it first setting up and when resuming in 'talk_to_blkback()'.
Then, blkback reads the advertised value when it connects with blkfront
and decides if it will use the persistent grants feature or not, and
advertises its decision to blkfront.  Blkfront reads the blkback's
decision and it also makes the decision for the use of the feature.

Commit 402c43ea6b ("xen-blkfront: Apply 'feature_persistent' parameter
when connect"), however, made the blkfront's read of the parameter for
disabling the advertisement, namely 'feature_persistent', to be done
when it negotiate, not when advertise.  Therefore blkfront advertises
without reading the parameter.  As the field for caching the parameter
value is zero-initialized, it always advertises as the feature is
disabled, so that the persistent grants feature becomes always disabled.

This commit fixes the issue by making the blkfront does parmeter caching
just before the advertisement.

Fixes: 402c43ea6b ("xen-blkfront: Apply 'feature_persistent' parameter when connect")
Cc: <stable@vger.kernel.org> # 5.10.x
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220831165824.94815-4-sj@kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15 11:32:02 +02:00
SeongJae Park
f210912d1a xen-blkfront: Advertise feature-persistent as user requested
commit 9f5e0fe5d0 upstream.

The advertisement of the persistent grants feature (writing
'feature-persistent' to xenbus) should mean not the decision for using
the feature but only the availability of the feature.  However, commit
74a852479c ("xen-blkfront: add a parameter for disabling of persistent
grants") made a field of blkfront, which was a place for saving only the
negotiation result, to be used for yet another purpose: caching of the
'feature_persistent' parameter value.  As a result, the advertisement,
which should follow only the parameter value, becomes inconsistent.

This commit fixes the misuse of the semantic by making blkfront saves
the parameter value in a separate place and advertises the support based
on only the saved value.

Fixes: 74a852479c ("xen-blkfront: add a parameter for disabling of persistent grants")
Cc: <stable@vger.kernel.org> # 5.10.x
Suggested-by: Juergen Gross <jgross@suse.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220831165824.94815-3-sj@kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08 11:11:39 +02:00
SeongJae Park
aa45c50703 xen-blkback: Advertise feature-persistent as user requested
commit 06ba5d2e94 upstream.

The advertisement of the persistent grants feature (writing
'feature-persistent' to xenbus) should mean not the decision for using
the feature but only the availability of the feature.  However, commit
aac8a70db2 ("xen-blkback: add a parameter for disabling of persistent
grants") made a field of blkback, which was a place for saving only the
negotiation result, to be used for yet another purpose: caching of the
'feature_persistent' parameter value.  As a result, the advertisement,
which should follow only the parameter value, becomes inconsistent.

This commit fixes the misuse of the semantic by making blkback saves the
parameter value in a separate place and advertises the support based on
only the saved value.

Fixes: aac8a70db2 ("xen-blkback: add a parameter for disabling of persistent grants")
Cc: <stable@vger.kernel.org> # 5.10.x
Suggested-by: Juergen Gross <jgross@suse.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220831165824.94815-2-sj@kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08 11:11:39 +02:00
Siddh Raman Pant
6858933131 loop: Check for overflow while configuring loop
commit c490a0b5a4 upstream.

The userspace can configure a loop using an ioctl call, wherein
a configuration of type loop_config is passed (see lo_ioctl()'s
case on line 1550 of drivers/block/loop.c). This proceeds to call
loop_configure() which in turn calls loop_set_status_from_info()
(see line 1050 of loop.c), passing &config->info which is of type
loop_info64*. This function then sets the appropriate values, like
the offset.

loop_device has lo_offset of type loff_t (see line 52 of loop.c),
which is typdef-chained to long long, whereas loop_info64 has
lo_offset of type __u64 (see line 56 of include/uapi/linux/loop.h).

The function directly copies offset from info to the device as
follows (See line 980 of loop.c):
	lo->lo_offset = info->lo_offset;

This results in an overflow, which triggers a warning in iomap_iter()
due to a call to iomap_iter_done() which has:
	WARN_ON_ONCE(iter->iomap.offset > iter->pos);

Thus, check for negative value during loop_set_status_from_info().

Bug report: https://syzkaller.appspot.com/bug?id=c620fe14aac810396d3c3edc9ad73848bf69a29e

Reported-and-tested-by: syzbot+a8e049cd3abd342936b6@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Siddh Raman Pant <code@siddh.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220823160810.181275-1-code@siddh.me
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-31 17:15:22 +02:00
Sergey Senozhatsky
56a4bccab9 zram: do not lookup algorithm in backends table
[ Upstream commit dc89997264 ]

Always use crypto_has_comp() so that crypto can lookup module, call
usermodhelper to load the modules, wait for usermodhelper to finish and so
on.  Otherwise crypto will do all of these steps under CPU hot-plug lock
and this looks like too much stuff to handle under the CPU hot-plug lock.
Besides this can end up in a deadlock when usermodhelper triggers a code
path that attempts to lock the CPU hot-plug lock, that zram already holds.

An example of such deadlock:

- path A. zram grabs CPU hot-plug lock, execs /sbin/modprobe from crypto
  and waits for modprobe to finish

disksize_store
 zcomp_create
  __cpuhp_state_add_instance
   __cpuhp_state_add_instance_cpuslocked
    zcomp_cpu_up_prepare
     crypto_alloc_base
      crypto_alg_mod_lookup
       call_usermodehelper_exec
        wait_for_completion_killable
         do_wait_for_common
          schedule

- path B. async work kthread that brings in scsi device. It wants to
  register CPUHP states at some point, and it needs the CPU hot-plug
  lock for that, which is owned by zram.

async_run_entry_fn
 scsi_probe_and_add_lun
  scsi_mq_alloc_queue
   blk_mq_init_queue
    blk_mq_init_allocated_queue
     blk_mq_realloc_hw_ctxs
      __cpuhp_state_add_instance
       __cpuhp_state_add_instance_cpuslocked
        mutex_lock
         schedule

- path C. modprobe sleeps, waiting for all aync works to finish.

load_module
 do_init_module
  async_synchronize_full
   async_synchronize_cookie_domain
    schedule

[senozhatsky@chromium.org: add comment]
  Link: https://lkml.kernel.org/r/20220624060606.1014474-1-senozhatsky@chromium.org
Link: https://lkml.kernel.org/r/20220622023501.517125-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:38:14 +02:00
SeongJae Park
135d9e0710 xen-blkfront: Apply 'feature_persistent' parameter when connect
commit 402c43ea6b upstream.

In some use cases[1], the backend is created while the frontend doesn't
support the persistent grants feature, but later the frontend can be
changed to support the feature and reconnect.  In the past, 'blkback'
enabled the persistent grants feature since it unconditionally checked
if frontend supports the persistent grants feature for every connect
('connect_ring()') and decided whether it should use persistent grans or
not.

However, commit aac8a70db2 ("xen-blkback: add a parameter for
disabling of persistent grants") has mistakenly changed the behavior.
It made the frontend feature support check to not be repeated once it
shown the 'feature_persistent' as 'false', or the frontend doesn't
support persistent grants.

Similar behavioral change has made on 'blkfront' by commit 74a852479c
("xen-blkfront: add a parameter for disabling of persistent grants").
This commit changes the behavior of the parameter to make effect for
every connect, so that the previous behavior of 'blkfront' can be
restored.

[1] https://lore.kernel.org/xen-devel/CAJwUmVB6H3iTs-C+U=v-pwJB7-_ZRHPxHzKRJZ22xEPW7z8a=g@mail.gmail.com/

Fixes: 74a852479c ("xen-blkfront: add a parameter for disabling of persistent grants")
Cc: <stable@vger.kernel.org> # 5.10.x
Signed-off-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Maximilian Heyne <mheyne@amazon.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220715225108.193398-4-sj@kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-21 15:16:22 +02:00
Maximilian Heyne
d4fb08e5a4 xen-blkback: Apply 'feature_persistent' parameter when connect
commit e94c6101e1 upstream.

In some use cases[1], the backend is created while the frontend doesn't
support the persistent grants feature, but later the frontend can be
changed to support the feature and reconnect.  In the past, 'blkback'
enabled the persistent grants feature since it unconditionally checked
if frontend supports the persistent grants feature for every connect
('connect_ring()') and decided whether it should use persistent grans or
not.

However, commit aac8a70db2 ("xen-blkback: add a parameter for
disabling of persistent grants") has mistakenly changed the behavior.
It made the frontend feature support check to not be repeated once it
shown the 'feature_persistent' as 'false', or the frontend doesn't
support persistent grants.

This commit changes the behavior of the parameter to make effect for
every connect, so that the previous workflow can work again as expected.

[1] https://lore.kernel.org/xen-devel/CAJwUmVB6H3iTs-C+U=v-pwJB7-_ZRHPxHzKRJZ22xEPW7z8a=g@mail.gmail.com/

Reported-by: Andrii Chepurnyi <andrii.chepurnyi82@gmail.com>
Fixes: aac8a70db2 ("xen-blkback: add a parameter for disabling of persistent grants")
Cc: <stable@vger.kernel.org> # 5.10.x
Signed-off-by: Maximilian Heyne <mheyne@amazon.de>
Signed-off-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Maximilian Heyne <mheyne@amazon.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220715225108.193398-3-sj@kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-21 15:16:22 +02:00
SeongJae Park
9e84088452 xen-blkback: fix persistent grants negotiation
commit fc9be616bb upstream.

Persistent grants feature can be used only when both backend and the
frontend supports the feature.  The feature was always supported by
'blkback', but commit aac8a70db2 ("xen-blkback: add a parameter for
disabling of persistent grants") has introduced a parameter for
disabling it runtime.

To avoid the parameter be updated while being used by 'blkback', the
commit caches the parameter into 'vbd->feature_gnt_persistent' in
'xen_vbd_create()', and then check if the guest also supports the
feature and finally updates the field in 'connect_ring()'.

However, 'connect_ring()' could be called before 'xen_vbd_create()', so
later execution of 'xen_vbd_create()' can wrongly overwrite 'true' to
'vbd->feature_gnt_persistent'.  As a result, 'blkback' could try to use
'persistent grants' feature even if the guest doesn't support the
feature.

This commit fixes the issue by moving the parameter value caching to
'xen_blkif_alloc()', which allocates the 'blkif'.  Because the struct
embeds 'vbd' object, which will be used by 'connect_ring()' later, this
should be called before 'connect_ring()' and therefore this should be
the right and safe place to do the caching.

Fixes: aac8a70db2 ("xen-blkback: add a parameter for disabling of persistent grants")
Cc: <stable@vger.kernel.org> # 5.10.x
Signed-off-by: Maximilian Heyne <mheyne@amazon.de>
Signed-off-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Maximilian Heyne <mheyne@amazon.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220715225108.193398-2-sj@kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-21 15:16:22 +02:00
Dan Carpenter
7a4b46784a null_blk: fix ida error handling in null_add_dev()
[ Upstream commit ee452a8d98 ]

There needs to be some error checking if ida_simple_get() fails.
Also call ida_free() if there are errors later.

Fixes: 94bc02e30f ("nullb: use ida to manage index")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YtEhXsr6vJeoiYhd@kili
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:03 +02:00
Roger Pau Monne
cbbd2d2531 xen/blkfront: force data bouncing when backend is untrusted
commit 2400617da7 upstream.

Split the current bounce buffering logic used with persistent grants
into it's own option, and allow enabling it independently of
persistent grants.  This allows to reuse the same code paths to
perform the bounce buffering required to avoid leaking contiguous data
in shared pages not part of the request fragments.

Reporting whether the backend is to be trusted can be done using a
module parameter, or from the xenstore frontend path as set by the
toolstack when adding the device.

This is CVE-2022-33742, part of XSA-403.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:52:22 +02:00
Roger Pau Monne
cfea428030 xen/blkfront: fix leaking data in shared pages
commit 2f446ffe9d upstream.

When allocating pages to be used for shared communication with the
backend always zero them, this avoids leaking unintended data present
on the pages.

This is CVE-2022-26365, part of XSA-403.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:52:22 +02:00
Yu Kuai
f72df77600 nbd: fix io hung while disconnecting device
[ Upstream commit 09dadb5985 ]

In our tests, "qemu-nbd" triggers a io hung:

INFO: task qemu-nbd:11445 blocked for more than 368 seconds.
      Not tainted 5.18.0-rc3-next-20220422-00003-g2176915513ca #884
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:qemu-nbd        state:D stack:    0 pid:11445 ppid:     1 flags:0x00000000
Call Trace:
 <TASK>
 __schedule+0x480/0x1050
 ? _raw_spin_lock_irqsave+0x3e/0xb0
 schedule+0x9c/0x1b0
 blk_mq_freeze_queue_wait+0x9d/0xf0
 ? ipi_rseq+0x70/0x70
 blk_mq_freeze_queue+0x2b/0x40
 nbd_add_socket+0x6b/0x270 [nbd]
 nbd_ioctl+0x383/0x510 [nbd]
 blkdev_ioctl+0x18e/0x3e0
 __x64_sys_ioctl+0xac/0x120
 do_syscall_64+0x35/0x80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fd8ff706577
RSP: 002b:00007fd8fcdfebf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000040000000 RCX: 00007fd8ff706577
RDX: 000000000000000d RSI: 000000000000ab00 RDI: 000000000000000f
RBP: 000000000000000f R08: 000000000000fbe8 R09: 000055fe497c62b0
R10: 00000002aff20000 R11: 0000000000000246 R12: 000000000000006d
R13: 0000000000000000 R14: 00007ffe82dc5e70 R15: 00007fd8fcdff9c0

"qemu-ndb -d" will call ioctl 'NBD_DISCONNECT' first, however, following
message was found:

block nbd0: Send disconnect failed -32

Which indicate that something is wrong with the server. Then,
"qemu-nbd -d" will call ioctl 'NBD_CLEAR_SOCK', however ioctl can't clear
requests after commit 2516ab1543fd("nbd: only clear the queue on device
teardown"). And in the meantime, request can't complete through timeout
because nbd_xmit_timeout() will always return 'BLK_EH_RESET_TIMER', which
means such request will never be completed in this situation.

Now that the flag 'NBD_CMD_INFLIGHT' can make sure requests won't
complete multiple times, switch back to call nbd_clear_sock() in
nbd_clear_sock_ioctl(), so that inflight requests can be cleared.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20220521073749.3146892-5-yukuai3@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:32:44 +02:00
Yu Kuai
122e4adaff nbd: fix race between nbd_alloc_config() and module removal
[ Upstream commit c55b2b983b ]

When nbd module is being removing, nbd_alloc_config() may be
called concurrently by nbd_genl_connect(), although try_module_get()
will return false, but nbd_alloc_config() doesn't handle it.

The race may lead to the leak of nbd_config and its related
resources (e.g, recv_workq) and oops in nbd_read_stat() due
to the unload of nbd module as shown below:

  BUG: kernel NULL pointer dereference, address: 0000000000000040
  Oops: 0000 [#1] SMP PTI
  CPU: 5 PID: 13840 Comm: kworker/u17:33 Not tainted 5.14.0+ #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
  Workqueue: knbd16-recv recv_work [nbd]
  RIP: 0010:nbd_read_stat.cold+0x130/0x1a4 [nbd]
  Call Trace:
   recv_work+0x3b/0xb0 [nbd]
   process_one_work+0x1ed/0x390
   worker_thread+0x4a/0x3d0
   kthread+0x12a/0x150
   ret_from_fork+0x22/0x30

Fixing it by checking the return value of try_module_get()
in nbd_alloc_config(). As nbd_alloc_config() may return ERR_PTR(-ENODEV),
assign nbd->config only when nbd_alloc_config() succeeds to ensure
the value of nbd->config is binary (valid or NULL).

Also adding a debug message to check the reference counter
of nbd_config during module removal.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20220521073749.3146892-3-yukuai3@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:32:44 +02:00
Yu Kuai
c0868f6e72 nbd: call genl_unregister_family() first in nbd_cleanup()
[ Upstream commit 06c4da89c2 ]

Otherwise there may be race between module removal and the handling of
netlink command, which can lead to the oops as shown below:

  BUG: kernel NULL pointer dereference, address: 0000000000000098
  Oops: 0002 [#1] SMP PTI
  CPU: 1 PID: 31299 Comm: nbd-client Tainted: G            E     5.14.0-rc4
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
  RIP: 0010:down_write+0x1a/0x50
  Call Trace:
   start_creating+0x89/0x130
   debugfs_create_dir+0x1b/0x130
   nbd_start_device+0x13d/0x390 [nbd]
   nbd_genl_connect+0x42f/0x748 [nbd]
   genl_family_rcv_msg_doit.isra.0+0xec/0x150
   genl_rcv_msg+0xe5/0x1e0
   netlink_rcv_skb+0x55/0x100
   genl_rcv+0x29/0x40
   netlink_unicast+0x1a8/0x250
   netlink_sendmsg+0x21b/0x430
   ____sys_sendmsg+0x2a4/0x2d0
   ___sys_sendmsg+0x81/0xc0
   __sys_sendmsg+0x62/0xb0
   __x64_sys_sendmsg+0x1f/0x30
   do_syscall_64+0x3b/0xc0
   entry_SYSCALL_64_after_hwframe+0x44/0xae
  Modules linked in: nbd(E-)

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20220521073749.3146892-2-yukuai3@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:32:44 +02:00
Christoph Hellwig
940b12435b virtio_blk: fix the discard_granularity and discard_alignment queue limits
[ Upstream commit 62952cc5bc ]

The discard_alignment queue limit is named a bit misleading means the
offset into the block device at which the discard granularity starts.

On the other hand the discard_sector_alignment from the virtio 1.1 looks
similar to what Linux uses as discard granularity (even if not very well
described):

  "discard_sector_alignment can be used by OS when splitting a request
   based on alignment. "

And at least qemu does set it to the discard granularity.

So stop setting the discard_alignment and use the virtio
discard_sector_alignment to set the discard granularity.

Fixes: 1f23816b8e ("virtio_blk: add discard and write zeroes support")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220418045314.360785-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:21:05 +02:00
Arnd Bergmann
bea6985099 drbd: fix duplicate array initializer
[ Upstream commit 33cb0917bb ]

There are two initializers for P_RETRY_WRITE:

drivers/block/drbd/drbd_main.c:3676:22: warning: initialized field overwritten [-Woverride-init]

Remove the first one since it was already ignored by the compiler
and reorder the list to match the enum definition. As P_ZEROES had
no entry, add that one instead.

Fixes: 036b17eaab ("drbd: Receiving part for the PROTOCOL_UPDATE packet")
Fixes: f31e583aa2 ("drbd: introduce P_ZEROES (REQ_OP_WRITE_ZEROES on the "wire")")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20220406190715.1938174-2-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:21:01 +02:00
Xie Yongji
8d33585ffa nbd: Fix hung on disconnect request if socket is closed before
[ Upstream commit 491bf8f236 ]

When userspace closes the socket before sending a disconnect
request, the following I/O requests will be blocked in
wait_for_reconnect() until dead timeout. This will cause the
following disconnect request also hung on blk_mq_quiesce_queue().
That means we have no way to disconnect a nbd device if there
are some I/O requests waiting for reconnecting until dead timeout.
It's not expected. So let's wake up the thread waiting for
reconnecting directly when a disconnect request is sent.

Reported-by: Xu Jianhai <zero.xu@bytedance.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20220322080639.142-1-xieyongji@bytedance.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:20:55 +02:00
Jakob Koschel
5a19f3c2d3 drbd: remove usage of list iterator variable after loop
[ Upstream commit 901aeda62e ]

In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to iterate through the list [1].

Since that variable should not be used past the loop iteration, a
separate variable is used to 'remember the current location within the
loop'.

To either continue iterating from that position or skip the iteration
(if the previous iteration was complete) list_prepare_entry() is used.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220331220349.885126-1-jakobkoschel@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-25 09:17:54 +02:00
Willy Tarreau
911b362678 floppy: use a statically allocated error counter
commit f71f01394f upstream.

Interrupt handler bad_flp_intr() may cause a UAF on the recently freed
request just to increment the error count.  There's no point keeping
that one in the request anyway, and since the interrupt handler uses a
static pointer to the error which cannot be kept in sync with the
pending request, better make it use a static error counter that's reset
for each new request.  This reset now happens when entering
redo_fd_request() for a new request via set_next_request().

One initial concern about a single error counter was that errors on one
floppy drive could be reported on another one, but this problem is not
real given that the driver uses a single drive at a time, as that
PC-compatible controllers also have this limitation by using shared
signals.  As such the error count is always for the "current" drive.

Reported-by: Minh Yuan <yuanmingbuaa@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Tested-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-25 09:17:51 +02:00
Lee Jones
efd1429fa9 block: drbd: drbd_nl: Make conversion to 'enum drbd_ret_code' explicit
commit 1f1e87b4dc upstream.

Fixes the following W=1 kernel build warning(s):

 from drivers/block/drbd/drbd_nl.c:24:
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_set_role’:
 drivers/block/drbd/drbd_nl.c:793:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c:795:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_attach’:
 drivers/block/drbd/drbd_nl.c:1965:10: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_connect’:
 drivers/block/drbd/drbd_nl.c:2690:10: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]
 drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_disconnect’:
 drivers/block/drbd/drbd_nl.c:2803:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion]

Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210312105530.2219008-8-lee.jones@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-15 20:00:08 +02:00
Willy Tarreau
54c028cfc4 floppy: disable FDRAWCMD by default
commit 233087ca06 upstream.

Minh Yuan reported a concurrency use-after-free issue in the floppy code
between raw_cmd_ioctl and seek_interrupt.

[ It turns out this has been around, and that others have reported the
  KASAN splats over the years, but Minh Yuan had a reproducer for it and
  so gets primary credit for reporting it for this fix   - Linus ]

The problem is, this driver tends to break very easily and nowadays,
nobody is expected to use FDRAWCMD anyway since it was used to
manipulate non-standard formats.  The risk of breaking the driver is
higher than the risk presented by this race, and accessing the device
requires privileges anyway.

Let's just add a config option to completely disable this ioctl and
leave it disabled by default.  Distros shouldn't use it, and only those
running on antique hardware might need to enable it.

Link: https://lore.kernel.org/all/000000000000b71cdd05d703f6bf@google.com/
Link: https://lore.kernel.org/lkml/CAKcFiNC=MfYVW-Jt9A3=FPJpTwCD2PL_ULNCpsCVE5s8ZeBQgQ@mail.gmail.com
Link: https://lore.kernel.org/all/CAEAjamu1FRhz6StCe_55XY5s389ZP_xmCF69k987En+1z53=eg@mail.gmail.com
Reported-by: Minh Yuan <yuanmingbuaa@gmail.com>
Reported-by: syzbot+8e8958586909d62b6840@syzkaller.appspotmail.com
Reported-by: cruise k <cruise4k@gmail.com>
Reported-by: Kyungtae Kim <kt0755@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Tested-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-09 09:04:56 +02:00
Lv Yunlong
594205b493 drbd: Fix five use after free bugs in get_initial_state
[ Upstream commit aadb22ba2f ]

In get_initial_state, it calls notify_initial_state_done(skb,..) if
cb->args[5]==1. If genlmsg_put() failed in notify_initial_state_done(),
the skb will be freed by nlmsg_free(skb).
Then get_initial_state will goto out and the freed skb will be used by
return value skb->len, which is a uaf bug.

What's worse, the same problem goes even further: skb can also be
freed in the notify_*_state_change -> notify_*_state calls below.
Thus 4 additional uaf bugs happened.

My patch lets the problem callee functions: notify_initial_state_done
and notify_*_state_change return an error code if errors happen.
So that the error codes could be propagated and the uaf bugs can be avoid.

v2 reports a compilation warning. This v3 fixed this warning and built
successfully in my local environment with no additional warnings.
v2: https://lore.kernel.org/patchwork/patch/1435218/

Fixes: a29728463b ("drbd: Backport the "events2" command")
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 21:01:06 +02:00
Chaitanya Kulkarni
012c572007 loop: use sysfs_emit() in the sysfs xxx show()
[ Upstream commit b27824d31f ]

sprintf does not know the PAGE_SIZE maximum of the temporary buffer
used for outputting sysfs content and it's possible to overrun the
PAGE_SIZE buffer length.

Use a generic sysfs_emit function that knows the size of the
temporary buffer and ensures that no overrun is done for offset
attribute in
loop_attr_[offset|sizelimit|autoclear|partscan|dio]_show() callbacks.

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Link: https://lore.kernel.org/r/20220215213310.7264-2-kch@nvidia.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:40:31 +02:00
Lars Ellenberg
fde8c5cad0 drbd: fix potential silent data corruption
commit f4329d1f84 upstream.

Scenario:
---------

bio chain generated by blk_queue_split().
Some split bio fails and propagates its error status to the "parent" bio.
But then the (last part of the) parent bio itself completes without error.

We would clobber the already recorded error status with BLK_STS_OK,
causing silent data corruption.

Reproducer:
-----------

How to trigger this in the real world within seconds:

DRBD on top of degraded parity raid,
small stripe_cache_size, large read_ahead setting.
Drop page cache (sysctl vm.drop_caches=1, fadvise "DONTNEED",
umount and mount again, "reboot").

Cause significant read ahead.

Large read ahead request is split by blk_queue_split().
Parts of the read ahead that are already in the stripe cache,
or find an available stripe cache to use, can be serviced.
Parts of the read ahead that would need "too much work",
would need to wait for a "stripe_head" to become available,
are rejected immediately.

For larger read ahead requests that are split in many pieces, it is very
likely that some "splits" will be serviced, but then the stripe cache is
exhausted/busy, and the remaining ones will be rejected.

Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Cc: <stable@vger.kernel.org> # 4.13.x
Link: https://lore.kernel.org/r/20220330185551.3553196-1-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-08 14:39:54 +02:00
Xie Yongji
39a70732eb virtio-blk: Use blk_validate_block_size() to validate block size
commit 57a13a5b81 upstream.

The block layer can't support a block size larger than
page size yet. And a block size that's too small or
not a power of two won't work either. If a misconfigured
device presents an invalid block size in configuration space,
it will result in the kernel crash something like below:

[  506.154324] BUG: kernel NULL pointer dereference, address: 0000000000000008
[  506.160416] RIP: 0010:create_empty_buffers+0x24/0x100
[  506.174302] Call Trace:
[  506.174651]  create_page_buffers+0x4d/0x60
[  506.175207]  block_read_full_page+0x50/0x380
[  506.175798]  ? __mod_lruvec_page_state+0x60/0xa0
[  506.176412]  ? __add_to_page_cache_locked+0x1b2/0x390
[  506.177085]  ? blkdev_direct_IO+0x4a0/0x4a0
[  506.177644]  ? scan_shadow_nodes+0x30/0x30
[  506.178206]  ? lru_cache_add+0x42/0x60
[  506.178716]  do_read_cache_page+0x695/0x740
[  506.179278]  ? read_part_sector+0xe0/0xe0
[  506.179821]  read_part_sector+0x36/0xe0
[  506.180337]  adfspart_check_ICS+0x32/0x320
[  506.180890]  ? snprintf+0x45/0x70
[  506.181350]  ? read_part_sector+0xe0/0xe0
[  506.181906]  bdev_disk_changed+0x229/0x5c0
[  506.182483]  blkdev_get_whole+0x6d/0x90
[  506.183013]  blkdev_get_by_dev+0x122/0x2d0
[  506.183562]  device_add_disk+0x39e/0x3c0
[  506.184472]  virtblk_probe+0x3f8/0x79b [virtio_blk]
[  506.185461]  virtio_dev_probe+0x15e/0x1d0 [virtio]

So let's use a block layer helper to validate the block size.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20211026144015.188-5-xieyongji@bytedance.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-08 14:39:48 +02:00
Xie Yongji
cca9d5035b virtio-blk: Don't use MAX_DISCARD_SEGMENTS if max_discard_seg is zero
[ Upstream commit dacc73ed0b ]

Currently the value of max_discard_segment will be set to
MAX_DISCARD_SEGMENTS (256) with no basis in hardware if device
set 0 to max_discard_seg in configuration space. It's incorrect
since the device might not be able to handle such large descriptors.
To fix it, let's follow max_segments restrictions in this case.

Fixes: 1f23816b8e ("virtio_blk: add discard and write zeroes support")
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20220304100058.116-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-16 14:15:57 +01:00
Juergen Gross
96219af4e5 xen/blkfront: don't use gnttab_query_foreign_access() for mapped status
Commit abf1fd5919 upstream.

It isn't enough to check whether a grant is still being in use by
calling gnttab_query_foreign_access(), as a mapping could be realized
by the other side just after having called that function.

In case the call was done in preparation of revoking a grant it is
better to do so via gnttab_end_foreign_access_ref() and check the
success of that operation instead.

For the ring allocation use alloc_pages_exact() in order to avoid
high order pages in case of a multi-page ring.

If a grant wasn't unmapped by the backend without persistent grants
being used, set the device state to "error".

This is CVE-2022-23036 / part of XSA-396.

Reported-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-11 12:11:54 +01:00
Xiongwei Song
0946fdd929 floppy: Add max size check for user space request
[ Upstream commit 545a32498c ]

We need to check the max request size that is from user space before
allocating pages. If the request size exceeds the limit, return -EINVAL.
This check can avoid the warning below from page allocator.

WARNING: CPU: 3 PID: 16525 at mm/page_alloc.c:5344 current_gfp_context include/linux/sched/mm.h:195 [inline]
WARNING: CPU: 3 PID: 16525 at mm/page_alloc.c:5344 __alloc_pages+0x45d/0x500 mm/page_alloc.c:5356
Modules linked in:
CPU: 3 PID: 16525 Comm: syz-executor.3 Not tainted 5.15.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
RIP: 0010:__alloc_pages+0x45d/0x500 mm/page_alloc.c:5344
Code: be c9 00 00 00 48 c7 c7 20 4a 97 89 c6 05 62 32 a7 0b 01 e8 74 9a 42 07 e9 6a ff ff ff 0f 0b e9 a0 fd ff ff 40 80 e5 3f eb 88 <0f> 0b e9 18 ff ff ff 4c 89 ef 44 89 e6 45 31 ed e8 1e 76 ff ff e9
RSP: 0018:ffffc90023b87850 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff92004770f0b RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000033 RDI: 0000000000010cc1
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff81bb4686 R11: 0000000000000001 R12: ffffffff902c1960
R13: 0000000000000033 R14: 0000000000000000 R15: ffff88804cf64a30
FS:  0000000000000000(0000) GS:ffff88802cd00000(0063) knlGS:00000000f44b4b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000002c921000 CR3: 000000004f507000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191
 __get_free_pages+0x8/0x40 mm/page_alloc.c:5418
 raw_cmd_copyin drivers/block/floppy.c:3113 [inline]
 raw_cmd_ioctl drivers/block/floppy.c:3160 [inline]
 fd_locked_ioctl+0x12e5/0x2820 drivers/block/floppy.c:3528
 fd_ioctl drivers/block/floppy.c:3555 [inline]
 fd_compat_ioctl+0x891/0x1b60 drivers/block/floppy.c:3869
 compat_blkdev_ioctl+0x3b8/0x810 block/ioctl.c:662
 __do_compat_sys_ioctl+0x1c7/0x290 fs/ioctl.c:972
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Reported-by: syzbot+23a02c7df2cf2bc93fa2@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20211116131033.27685-1-sxwjean@me.com
Signed-off-by: Xiongwei Song <sxwjean@gmail.com>
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:54:14 +01:00
Tasos Sahanidis
04fdd426ce floppy: Fix hang in watchdog when disk is ejected
[ Upstream commit fb48febce7 ]

When the watchdog detects a disk change, it calls cancel_activity(),
which in turn tries to cancel the fd_timer delayed work.

In the above scenario, fd_timer_fn is set to fd_watchdog(), meaning
it is trying to cancel its own work.
This results in a hang as cancel_delayed_work_sync() is waiting for the
watchdog (itself) to return, which never happens.

This can be reproduced relatively consistently by attempting to read a
broken floppy, and ejecting it while IO is being attempted and retried.

To resolve this, this patch calls cancel_delayed_work() instead, which
cancels the work without waiting for the watchdog to return and finish.

Before this regression was introduced, the code in this section used
del_timer(), and not del_timer_sync() to delete the watchdog timer.

Link: https://lore.kernel.org/r/399e486c-6540-db27-76aa-7a271b061f76@tasossah.com
Fixes: 070ad7e793 ("floppy: convert to delayed work and single-thread wq")
Signed-off-by: Tasos Sahanidis <tasos@tasossah.com>
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:53:53 +01:00
Juergen Gross
8ac3b6ee7c xen/blkfront: harden blkfront against event channel storms
commit 0fd08a34e8 upstream.

The Xen blkfront driver is still vulnerable for an attack via excessive
number of events sent by the backend. Fix that by using lateeoi event
channels.

This is part of XSA-391

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-22 09:30:59 +01:00
Juergen Gross
1ffb20f052 xen/blkfront: don't trust the backend response data blindly
commit b94e4b147f upstream.

Today blkfront will trust the backend to send only sane response data.
In order to avoid privilege escalations or crashes in case of malicious
backends verify the data to be within expected limits. Especially make
sure that the response always references an outstanding request.

Introduce a new state of the ring BLKIF_STATE_ERROR which will be
switched to in case an inconsistency is being detected. Recovering from
this state is possible only via removing and adding the virtual device
again (e.g. via a suspend/resume cycle).

Make all warning messages issued due to valid error responses rate
limited in order to avoid message floods being triggered by a malicious
backend.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20210730103854.12681-4-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-01 09:19:09 +01:00
Juergen Gross
8e147855fc xen/blkfront: don't take local copy of a request from the ring page
commit 8f5a695d99 upstream.

In order to avoid a malicious backend being able to influence the local
copy of a request build the request locally first and then copy it to
the ring page instead of doing it the other way round as today.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20210730103854.12681-3-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-01 09:19:09 +01:00
Juergen Gross
273f04d5d1 xen/blkfront: read response from backend only once
commit 71b66243f9 upstream.

In order to avoid problems in case the backend is modifying a response
on the ring page while the frontend has already seen it, just read the
response into a local buffer in one go and then operate on that buffer
only.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20210730103854.12681-2-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-01 09:19:09 +01:00
Xie Yongji
04e46514fe loop: Use blk_validate_block_size() to validate block size
commit af3c570fb0 upstream.

Remove loop_validate_block_size() and use the block layer helper
to validate block size.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20211026144015.188-4-xieyongji@bytedance.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Cc: Tadeusz Struk <tadeusz.struk@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-21 13:46:35 +01:00
Dan Carpenter
7091fcc75f zram: off by one in read_block_state()
[ Upstream commit a88e03cf3d ]

snprintf() returns the number of bytes it would have printed if there
were space.  But it does not count the NUL terminator.  So that means
that if "count == copied" then this has already overflowed by one
character.

This bug likely isn't super harmful in real life.

Link: https://lkml.kernel.org/r/20210916130404.GA25094@kili
Fixes: c0265342bf ("zram: introduce zram memory tracking")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18 14:04:27 +01:00
Greg Kroah-Hartman
0daa75bf75 Revert "block: nbd: add sanity check for first_minor"
This reverts commit 4b21d4e820 which is
commit b1a811633f upstream.

The backport of this is reported to be causing some problems, so revert
this for now until they are worked out.

Link: https://lore.kernel.org/r/CACPK8XfUWoOHr-0RwRoYoskia4fbAbZ7DYf5wWBnv6qUnGq18w@mail.gmail.com
Reported-by: Joel Stanley <joel@jms.id.au>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Pavel Skripkin <paskripkin@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-16 12:51:23 +02:00
Pavel Skripkin
4b21d4e820 block: nbd: add sanity check for first_minor
[ Upstream commit b1a811633f ]

Syzbot hit WARNING in internal_create_group(). The problem was in
too big disk->first_minor.

disk->first_minor is initialized by value, which comes from userspace
and there wasn't any sanity checks about value correctness. It can cause
duplicate creation of sysfs files/links, because disk->first_minor will
be passed to MKDEV() which causes truncation to byte. Since maximum
minor value is 0xff, let's check if first_minor is correct minor number.

NOTE: the root case of the reported warning was in wrong error handling
in register_disk(), but we can avoid passing knowingly wrong values to
sysfs API, because sysfs error messages can confuse users. For example:
user passed 1048576 as index, but sysfs complains about duplicate
creation of /dev/block/43:0. It's not obvious how 1048576 becomes 0.
Log and reproducer for above example can be found on syzkaller bug
report page.

Link: https://syzkaller.appspot.com/bug?id=03c2ae9146416edf811958d5fd7acfab75b143d1
Fixes: b0d9111a2d ("nbd: use an idr to keep track of nbd devices")
Reported-by: syzbot+9937dc42271cd87d4b98@syzkaller.appspotmail.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-15 09:50:29 +02:00
Christoph Hellwig
2808d59fb2 cryptoloop: add a deprecation warning
[ Upstream commit 222013f9ac ]

Support for cryptoloop has been officially marked broken and deprecated
in favor of dm-crypt (which supports the same broken algorithms if
needed) in Linux 2.6.4 (released in March 2004), and support for it has
been entirely removed from losetup in util-linux 2.23 (released in April
2013).  Add a warning and a deprecation schedule.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210827163250.255325-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-08 08:49:01 +02:00
Denis Efremov
17982c664f Revert "floppy: reintroduce O_NDELAY fix"
commit c7e9d00203 upstream.

The patch breaks userspace implementations (e.g. fdutils) and introduces
regressions in behaviour. Previously, it was possible to O_NDELAY open a
floppy device with no media inserted or with write protected media without
an error. Some userspace tools use this particular behavior for probing.

It's not the first time when we revert this patch. Previous revert is in
commit f2791e7ead (Revert "floppy: refactor open() flags handling").

This reverts commit 8a0c014cd2.

Link: https://lore.kernel.org/linux-block/de10cb47-34d1-5a88-7751-225ca380f735@compro.net/
Reported-by: Mark Hounschell <markh@compro.net>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Wim Osterholt <wim@djo.tudelft.nl>
Cc: Kurt Garloff <kurt@garloff.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-03 10:09:31 +02:00
Xie Yongji
e0ee8d9c31 nbd: Aovid double completion of a request
[ Upstream commit cddce01160 ]

There is a race between iterating over requests in
nbd_clear_que() and completing requests in recv_work(),
which can lead to double completion of a request.

To fix it, flush the recv worker before iterating over
the requests and don't abort the completed request
while iterating.

Fixes: 96d97e1782 ("nbd: clear_sock on netlink disconnect")
Reported-by: Jiang Yadong <jiangyadong@bytedance.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20210813151330.96-1-xieyongji@bytedance.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-18 08:59:14 +02:00
Ilya Dryomov
8571daace5 rbd: always kick acquire on "acquired" and "released" notifications
commit 8798d070d4 upstream.

Skipping the "lock has been released" notification if the lock owner
is not what we expect based on owner_cid can lead to I/O hangs.
One example is our own notifications: because owner_cid is cleared
in rbd_unlock(), when we get our own notification it is processed as
unexpected/duplicate and maybe_kick_acquire() isn't called.  If a peer
that requested the lock then doesn't go through with acquiring it,
I/O requests that came in while the lock was being quiesced would
be stalled until another I/O request is submitted and kicks acquire
from rbd_img_exclusive_lock().

This makes the comment in rbd_release_lock() actually true: prior to
this change the canceled work was being requeued in response to the
"lock has been acquired" notification from rbd_handle_acquired_lock().

Cc: stable@vger.kernel.org # 5.3+
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Tested-by: Robin Geuze <robin.geuze@nl.team.blue>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-28 14:35:46 +02:00
Ilya Dryomov
2f3731de5e rbd: don't hold lock_rwsem while running_list is being drained
commit ed9eb71085 upstream.

Currently rbd_quiesce_lock() holds lock_rwsem for read while blocking
on releasing_wait completion.  On the I/O completion side, each image
request also needs to take lock_rwsem for read.  Because rw_semaphore
implementation doesn't allow new readers after a writer has indicated
interest in the lock, this can result in a deadlock if something that
needs to take lock_rwsem for write gets involved.  For example:

1. watch error occurs
2. rbd_watch_errcb() takes lock_rwsem for write, clears owner_cid and
   releases lock_rwsem
3. after reestablishing the watch, rbd_reregister_watch() takes
   lock_rwsem for write and calls rbd_reacquire_lock()
4. rbd_quiesce_lock() downgrades lock_rwsem to for read and blocks on
   releasing_wait until running_list becomes empty
5. another watch error occurs
6. rbd_watch_errcb() blocks trying to take lock_rwsem for write
7. no in-flight image request can complete and delete itself from
   running_list because lock_rwsem won't be granted anymore

A similar scenario can occur with "lock has been acquired" and "lock
has been released" notification handers which also take lock_rwsem for
write to update owner_cid.

We don't actually get anything useful from sitting on lock_rwsem in
rbd_quiesce_lock() -- owner_cid updates certainly don't need to be
synchronized with.  In fact the whole owner_cid tracking logic could
probably be removed from the kernel client because we don't support
proxied maintenance operations.

Cc: stable@vger.kernel.org # 5.3+
URL: https://tracker.ceph.com/issues/42757
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Tested-by: Robin Geuze <robin.geuze@nl.team.blue>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-28 14:35:46 +02:00
Xie Yongji
cd24da0db9 virtio-blk: Fix memory leak among suspend/resume procedure
[ Upstream commit b71ba22e7c ]

The vblk->vqs should be freed before we call init_vqs()
in virtblk_restore().

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20210517084332.280-1-xieyongji@bytedance.com
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:05:49 +02:00
Mauricio Faria de Oliveira
fd6625a1ec loop: fix I/O error on fsync() in detached loop devices
commit 4ceddce55e upstream.

There's an I/O error on fsync() in a detached loop device
if it has been previously attached.

The issue is write cache is enabled in the attach path in
loop_configure() but it isn't disabled in the detach path;
thus it remains enabled in the block device regardless of
whether it is attached or not.

Now fsync() can get an I/O request that will just be failed
later in loop_queue_rq() as device's state is not 'Lo_bound'.

So, disable write cache in the detach path.

Do so based on the queue flag, not the loop device flag for
read-only (used to enable) as the queue flag can be changed
via sysfs even on read-only loop devices (e.g., losetup -r.)

Test-case:

    # DEV=/dev/loop7

    # IMG=/tmp/image
    # truncate --size 1M $IMG

    # losetup $DEV $IMG
    # losetup -d $DEV

Before:

    # strace -e fsync parted -s $DEV print 2>&1 | grep fsync
    fsync(3)                                = -1 EIO (Input/output error)
    Warning: Error fsyncing/closing /dev/loop7: Input/output error
    [  982.529929] blk_update_request: I/O error, dev loop7, sector 0 op 0x1:(WRITE) flags 0x800 phys_seg 0 prio class 0

After:

    # strace -e fsync parted -s $DEV print 2>&1 | grep fsync
    fsync(3)                                = 0

Co-developed-by: Eric Desrochers <eric.desrochers@canonical.com>
Signed-off-by: Eric Desrochers <eric.desrochers@canonical.com>
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Tested-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-19 09:44:55 +02:00
Kristian Klausen
a7e18f57ed loop: Fix missing discard support when using LOOP_CONFIGURE
commit 2b9ac22b12 upstream.

Without calling loop_config_discard() the discard flag and parameters
aren't set/updated for the loop device and worst-case they could
indicate discard support when it isn't the case (ex: if the
LOOP_SET_STATUS ioctl was used with a different file prior to
LOOP_CONFIGURE).

Cc: <stable@vger.kernel.org> # 5.8.x-
Fixes: 3448914e8c ("loop: Add LOOP_CONFIGURE ioctl")
Signed-off-by: Kristian Klausen <kristian@klausen.dk>
Link: https://lore.kernel.org/r/20210618115157.31452-1-kristian@klausen.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14 16:55:46 +02:00
Sun Ke
cde4b55cfb nbd: Fix NULL pointer in flush_workqueue
[ Upstream commit 79ebe9110f ]

Open /dev/nbdX first, the config_refs will be 1 and
the pointers in nbd_device are still null. Disconnect
/dev/nbdX, then reference a null recv_workq. The
protection by config_refs in nbd_genl_disconnect is useless.

[  656.366194] BUG: kernel NULL pointer dereference, address: 0000000000000020
[  656.368943] #PF: supervisor write access in kernel mode
[  656.369844] #PF: error_code(0x0002) - not-present page
[  656.370717] PGD 10cc87067 P4D 10cc87067 PUD 1074b4067 PMD 0
[  656.371693] Oops: 0002 [#1] SMP
[  656.372242] CPU: 5 PID: 7977 Comm: nbd-client Not tainted 5.11.0-rc5-00040-g76c057c84d28 #1
[  656.373661] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
[  656.375904] RIP: 0010:mutex_lock+0x29/0x60
[  656.376627] Code: 00 0f 1f 44 00 00 55 48 89 fd 48 83 05 6f d7 fe 08 01 e8 7a c3 ff ff 48 83 05 6a d7 fe 08 01 31 c0 65 48 8b 14 25 00 6d 01 00 <f0> 48 0f b1 55 d
[  656.378934] RSP: 0018:ffffc900005eb9b0 EFLAGS: 00010246
[  656.379350] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[  656.379915] RDX: ffff888104cf2600 RSI: ffffffffaae8f452 RDI: 0000000000000020
[  656.380473] RBP: 0000000000000020 R08: 0000000000000000 R09: ffff88813bd6b318
[  656.381039] R10: 00000000000000c7 R11: fefefefefefefeff R12: ffff888102710b40
[  656.381599] R13: ffffc900005eb9e0 R14: ffffffffb2930680 R15: ffff88810770ef00
[  656.382166] FS:  00007fdf117ebb40(0000) GS:ffff88813bd40000(0000) knlGS:0000000000000000
[  656.382806] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  656.383261] CR2: 0000000000000020 CR3: 0000000100c84000 CR4: 00000000000006e0
[  656.383819] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  656.384370] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  656.384927] Call Trace:
[  656.385111]  flush_workqueue+0x92/0x6c0
[  656.385395]  nbd_disconnect_and_put+0x81/0xd0
[  656.385716]  nbd_genl_disconnect+0x125/0x2a0
[  656.386034]  genl_family_rcv_msg_doit.isra.0+0x102/0x1b0
[  656.386422]  genl_rcv_msg+0xfc/0x2b0
[  656.386685]  ? nbd_ioctl+0x490/0x490
[  656.386954]  ? genl_family_rcv_msg_doit.isra.0+0x1b0/0x1b0
[  656.387354]  netlink_rcv_skb+0x62/0x180
[  656.387638]  genl_rcv+0x34/0x60
[  656.387874]  netlink_unicast+0x26d/0x590
[  656.388162]  netlink_sendmsg+0x398/0x6c0
[  656.388451]  ? netlink_rcv_skb+0x180/0x180
[  656.388750]  ____sys_sendmsg+0x1da/0x320
[  656.389038]  ? ____sys_recvmsg+0x130/0x220
[  656.389334]  ___sys_sendmsg+0x8e/0xf0
[  656.389605]  ? ___sys_recvmsg+0xa2/0xf0
[  656.389889]  ? handle_mm_fault+0x1671/0x21d0
[  656.390201]  __sys_sendmsg+0x6d/0xe0
[  656.390464]  __x64_sys_sendmsg+0x23/0x30
[  656.390751]  do_syscall_64+0x45/0x70
[  656.391017]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

To fix it, just add if (nbd->recv_workq) to nbd_disconnect_and_put().

Fixes: e9e006f5fc ("nbd: fix max number of supported devs")
Signed-off-by: Sun Ke <sunke32@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20210512114331.1233964-2-sunke32@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19 10:13:14 +02:00
Md Haris Iqbal
3d808916d2 block/rnbd-clt: Check the return value of the function rtrs_clt_query
[ Upstream commit 1056ad829e ]

In case none of the paths are in connected state, the function
rtrs_clt_query returns an error. In such a case, error out since the
values in the rtrs_attrs structure would be garbage.

Fixes: f7a7a5c228 ("block/rnbd: client: main functionality")
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Reviewed-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Link: https://lore.kernel.org/r/20210428061359.206794-4-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19 10:13:06 +02:00
Md Haris Iqbal
c1a90296a9 block/rnbd-clt: Change queue_depth type in rnbd_clt_session to size_t
[ Upstream commit 80d43cbd46 ]

The member queue_depth in the structure rnbd_clt_session is read from the
rtrs client side using the function rtrs_clt_query, which in turn is read
from the rtrs_clt structure. It should really be of type size_t.

Fixes: 90426e89f5 ("block/rnbd: client: private header with client structs and functions")
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Reviewed-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Link: https://lore.kernel.org/r/20210428061359.206794-2-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19 10:13:06 +02:00
Lv Yunlong
5378c92425 drivers/block/null_blk/main: Fix a double free in null_init.
[ Upstream commit 72ce11ddfa ]

In null_init, null_add_dev(dev) is called.
In null_add_dev, it calls null_free_zoned_dev(dev) to free dev->zones
via kvfree(dev->zones) in out_cleanup_zone branch and returns err.
Then null_init accept the err code and then calls null_free_dev(dev).

But in null_free_dev(dev), dev->zones is freed again by
null_free_zoned_dev().

My patch set dev->zones to NULL in null_free_zoned_dev() after
kvfree(dev->zones) is called, to avoid the double free.

Fixes: 2984c8684f ("nullb: factor disk parameters")
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Link: https://lore.kernel.org/r/20210426143229.7374-1-lyl2019@mail.ustc.edu.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:28 +02:00
Paul Durrant
bbe9de67ac xen-blkback: fix compatibility bug with single page rings
[ Upstream commit d75e7f63b7 ]

Prior to commit 4a8c31a1c6 ("xen/blkback: rework connect_ring() to avoid
inconsistent xenstore 'ring-page-order' set by malicious blkfront"), the
behaviour of xen-blkback when connecting to a frontend was:

- read 'ring-page-order'
- if not present then expect a single page ring specified by 'ring-ref'
- else expect a ring specified by 'ring-refX' where X is between 0 and
  1 << ring-page-order

This was correct behaviour, but was broken by the afforementioned commit to
become:

- read 'ring-page-order'
- if not present then expect a single page ring (i.e. ring-page-order = 0)
- expect a ring specified by 'ring-refX' where X is between 0 and
  1 << ring-page-order
- if that didn't work then see if there's a single page ring specified by
  'ring-ref'

This incorrect behaviour works most of the time but fails when a frontend
that sets 'ring-page-order' is unloaded and replaced by one that does not
because, instead of reading 'ring-ref', xen-blkback will read the stale
'ring-ref0' left around by the previous frontend will try to map the wrong
grant reference.

This patch restores the original behaviour.

Fixes: 4a8c31a1c6 ("xen/blkback: rework connect_ring() to avoid inconsistent xenstore 'ring-page-order' set by malicious blkfront")
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Reviewed-by: Dongli Zhang <dongli.zhang@oracle.com>
Reviewed-by: "Roger Pau Monné" <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20210202175659.18452-1-paul@xen.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:21 +02:00