1
0
Fork 0
Commit Graph

279 Commits (redonkable)

Author SHA1 Message Date
Christoph Hellwig 81dcfdb9a0 nbd: fix a block_device refcount leak in nbd_release
[ Upstream commit 2bd645b2d3 ]

bdget_disk needs to be paired with bdput to not leak a reference
on the block device inode.

Fixes: 08ba91ee6e ("nbd: Add the nbd NBD_DISCONNECT_ON_CLOSE config flag.")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-18 19:20:27 +01:00
Ming Lei 95fda70d39 nbd: don't update block size after device is started
[ Upstream commit b40813ddcd ]

Mounted NBD device can be resized, one use case is rbd-nbd.

Fix the issue by setting up default block size, then not touch it
in nbd_size_update() any more. This kind of usage is aligned with loop
which has same use case too.

Cc: stable@vger.kernel.org
Fixes: c8a83a6b54 ("nbd: Use set_blocksize() to set device blocksize")
Reported-by: lining <lining2020x@163.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Jan Kara <jack@suse.cz>
Tested-by: lining <lining2020x@163.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-18 19:20:15 +01:00
Xiubo Li 742fd49cf8 nbd: make the config put is called before the notifying the waiter
[ Upstream commit 87aac3a80a ]

There has one race case for ceph's rbd-nbd tool. When do mapping
it may fail with EBUSY from ioctl(nbd, NBD_DO_IT), but actually
the nbd device has already unmaped.

It dues to if just after the wake_up(), the recv_work() is scheduled
out and defers calling the nbd_config_put(), though the map process
has exited the "nbd->recv_task" is not cleared.

Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-05 11:43:22 +01:00
Hou Pu c756635246 nbd: restore default timeout when setting it to zero
[ Upstream commit acb19e17c5 ]

If we configured io timeout of nbd0 to 100s. Later after we
finished using it, we configured nbd0 again and set the io
timeout to 0. We expect it would timeout after 30 seconds
and keep retry. But in fact we could not change the timeout
when we set it to 0. the timeout is still the original 100s.

So change the timeout to default 30s when we set it to zero.
It also behaves same as commit 2da22da573 ("nbd: fix zero
cmd timeout handling v2").

It becomes more important if we were reconfigure a nbd device
and the io timeout it set to zero. Because it could take 30s
to detect the new socket and thus io could be completed more
quickly compared to 100s.

Signed-off-by: Hou Pu <houpu@bytedance.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-09 19:12:22 +02:00
Zheng Bin 2a4c5ff12f nbd: Fix memory leak in nbd_add_socket
[ Upstream commit 579dd91ab3 ]

When adding first socket to nbd, if nsock's allocation failed, the data
structure member "config->socks" was reallocated, but the data structure
member "config->num_connections" was not updated. A memory leak will occur
then because the function "nbd_config_put" will free "config->socks" only
when "config->num_connections" is not zero.

Fixes: 03bf73c315 ("nbd: prevent memory leak")
Reported-by: syzbot+934037347002901b8d2a@syzkaller.appspotmail.com
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-16 08:16:40 +02:00
Sun Ke 25cbba5d4e nbd: add a flush_workqueue in nbd_start_device
[ Upstream commit 5c0dd228b5 ]

When kzalloc fail, may cause trying to destroy the
workqueue from inside the workqueue.

If num_connections is m (2 < m), and NO.1 ~ NO.n
(1 < n < m) kzalloc are successful. The NO.(n + 1)
failed. Then, nbd_start_device will return ENOMEM
to nbd_start_device_ioctl, and nbd_start_device_ioctl
will return immediately without running flush_workqueue.
However, we still have n recv threads. If nbd_release
run first, recv threads may have to drop the last
config_refs and try to destroy the workqueue from
inside the workqueue.

To fix it, add a flush_workqueue in nbd_start_device.

Fixes: e9e006f5fc ("nbd: fix max number of supported devs")
Signed-off-by: Sun Ke <sunke32@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:31 +01:00
Mike Christie b3ead320dc nbd: fix shutdown and recv work deadlock v2
commit 1c05839aa9 upstream.

This fixes a regression added with:

commit e9e006f5fc
Author: Mike Christie <mchristi@redhat.com>
Date:   Sun Aug 4 14:10:06 2019 -0500

    nbd: fix max number of supported devs

where we can deadlock during device shutdown. The problem occurs if
the recv_work's nbd_config_put occurs after nbd_start_device_ioctl has
returned and the userspace app has droppped its reference via closing
the device and running nbd_release. The recv_work nbd_config_put call
would then drop the refcount to zero and try to destroy the config which
would try to do destroy_workqueue from the recv work.

This patch just has nbd_start_device_ioctl do a flush_workqueue when it
wakes so we know after the ioctl returns running works have exited. This
also fixes a possible race where we could try to reuse the device while
old recv_works are still running.

Cc: stable@vger.kernel.org
Fixes: e9e006f5fc ("nbd: fix max number of supported devs")
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-31 16:46:34 +01:00
Navid Emamdoost abf404dfa5 nbd: prevent memory leak
commit 03bf73c315 upstream.

In nbd_add_socket when krealloc succeeds, if nsock's allocation fail the
reallocted memory is leak. The correct behaviour should be assigning the
reallocted memory to config->socks right after success.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-29 10:09:47 +01:00
Sun Ke dff10bbea4 nbd:fix memory leak in nbd_get_socket()
Before returning NULL, put the sock first.

Cc: stable@vger.kernel.org
Fixes: cf1b2326b7 ("nbd: verify socket is supported during setup")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Sun Ke <sunke32@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-19 09:23:26 -07:00
Mike Christie cf1b2326b7 nbd: verify socket is supported during setup
nbd requires socket families to support the shutdown method so the nbd
recv workqueue can be woken up from its sock_recvmsg call. If the socket
does not support the callout we will leave recv works running or get hangs
later when the device or module is removed.

This adds a check during socket connection/reconnection to make sure the
socket being passed in supports the needed callout.

Reported-by: syzbot+24c12fa8d218ed26011a@syzkaller.appspotmail.com
Fixes: e9e006f5fc ("nbd: fix max number of supported devs")
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-25 14:37:21 -06:00
Josef Bacik 7ce23e8e0a nbd: handle racing with error'ed out commands
We hit the following warning in production

print_req_error: I/O error, dev nbd0, sector 7213934408 flags 80700
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 25 PID: 32407 at lib/refcount.c:190 refcount_sub_and_test_checked+0x53/0x60
Workqueue: knbd-recv recv_work [nbd]
RIP: 0010:refcount_sub_and_test_checked+0x53/0x60
Call Trace:
 blk_mq_free_request+0xb7/0xf0
 blk_mq_complete_request+0x62/0xf0
 recv_work+0x29/0xa1 [nbd]
 process_one_work+0x1f5/0x3f0
 worker_thread+0x2d/0x3d0
 ? rescuer_thread+0x340/0x340
 kthread+0x111/0x130
 ? kthread_create_on_node+0x60/0x60
 ret_from_fork+0x1f/0x30
---[ end trace b079c3c67f98bb7c ]---

This was preceded by us timing out everything and shutting down the
sockets for the device.  The problem is we had a request in the queue at
the same time, so we completed the request twice.  This can actually
happen in a lot of cases, we fail to get a ref on our config, we only
have one connection and just error out the command, etc.

Fix this by checking cmd->status in nbd_read_stat.  We only change this
under the cmd->lock, so we are safe to check this here and see if we've
already error'ed this command out, which would indicate that we've
completed it as well.

Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-25 14:20:03 -06:00
Josef Bacik de6346ecbc nbd: protect cmd->status with cmd->lock
We already do this for the most part, except in timeout and clear_req.
For the timeout case we take the lock after we grab a ref on the config,
but that isn't really necessary because we're safe to touch the cmd at
this point, so just move the order around.

For the clear_req cause this is initiated by the user, so again is safe.

Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-25 14:20:01 -06:00
Xiubo Li 862488105b nbd: fix possible sysfs duplicate warning
1. nbd_put takes the mutex and drops nbd->ref to 0. It then does
idr_remove and drops the mutex.

2. nbd_genl_connect takes the mutex. idr_find/idr_for_each fails
to find an existing device, so it does nbd_dev_add.

3. just before the nbd_put could call nbd_dev_remove or not finished
totally, but if nbd_dev_add try to add_disk, we can hit:

debugfs: Directory 'nbd1' with parent 'block' already present!

This patch will make sure all the disk add/remove stuff are done
by holding the nbd_index_mutex lock.

Reported-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-10 09:44:56 -06:00
Xiubo Li 8454d68563 nbd: fix possible page fault for nbd disk
When the NBD_CFLAG_DESTROY_ON_DISCONNECT flag is set and at the same
time when the socket is closed due to the server daemon is restarted,
just before the last DISCONNET is totally done if we start a new connection
by using the old nbd_index, there will be crashing randomly, like:

<3>[  110.151949] block nbd1: Receive control failed (result -32)
<1>[  110.152024] BUG: unable to handle page fault for address: 0000058000000840
<1>[  110.152063] #PF: supervisor read access in kernel mode
<1>[  110.152083] #PF: error_code(0x0000) - not-present page
<6>[  110.152094] PGD 0 P4D 0
<4>[  110.152106] Oops: 0000 [#1] SMP PTI
<4>[  110.152120] CPU: 0 PID: 6698 Comm: kworker/u5:1 Kdump: loaded Not tainted 5.3.0-rc4+ #2
<4>[  110.152136] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
<4>[  110.152166] Workqueue: knbd-recv recv_work [nbd]
<4>[  110.152187] RIP: 0010:__dev_printk+0xd/0x67
<4>[  110.152206] Code: 10 e8 c5 fd ff ff 48 8b 4c 24 18 65 48 33 0c 25 28 00 [...]
<4>[  110.152244] RSP: 0018:ffffa41581f13d18 EFLAGS: 00010206
<4>[  110.152256] RAX: ffffa41581f13d30 RBX: ffff96dd7374e900 RCX: 0000000000000000
<4>[  110.152271] RDX: ffffa41581f13d20 RSI: 00000580000007f0 RDI: ffffffff970ec24f
<4>[  110.152285] RBP: ffffa41581f13d80 R08: ffff96dd7fc17908 R09: 0000000000002e56
<4>[  110.152299] R10: ffffffff970ec24f R11: 0000000000000003 R12: ffff96dd7374e900
<4>[  110.152313] R13: 0000000000000000 R14: ffff96dd7374e9d8 R15: ffff96dd6e3b02c8
<4>[  110.152329] FS:  0000000000000000(0000) GS:ffff96dd7fc00000(0000) knlGS:0000000000000000
<4>[  110.152362] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4>[  110.152383] CR2: 0000058000000840 CR3: 0000000067cc6002 CR4: 00000000001606f0
<4>[  110.152401] Call Trace:
<4>[  110.152422]  _dev_err+0x6c/0x83
<4>[  110.152435]  nbd_read_stat.cold+0xda/0x578 [nbd]
<4>[  110.152448]  ? __switch_to_asm+0x34/0x70
<4>[  110.152468]  ? __switch_to_asm+0x40/0x70
<4>[  110.152478]  ? __switch_to_asm+0x34/0x70
<4>[  110.152491]  ? __switch_to_asm+0x40/0x70
<4>[  110.152501]  ? __switch_to_asm+0x34/0x70
<4>[  110.152511]  ? __switch_to_asm+0x40/0x70
<4>[  110.152522]  ? __switch_to_asm+0x34/0x70
<4>[  110.152533]  recv_work+0x35/0x9e [nbd]
<4>[  110.152547]  process_one_work+0x19d/0x340
<4>[  110.152558]  worker_thread+0x50/0x3b0
<4>[  110.152568]  kthread+0xfb/0x130
<4>[  110.152577]  ? process_one_work+0x340/0x340
<4>[  110.152609]  ? kthread_park+0x80/0x80
<4>[  110.152637]  ret_from_fork+0x35/0x40

This is very easy to reproduce by running the nbd-runner.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-09-17 20:03:49 -06:00
Xiubo Li ec76a7b922 nbd: rename the runtime flags as NBD_RT_ prefixed
Preparing for the destory when disconnecting crash fixing.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-09-17 20:03:49 -06:00
Mike Christie e9e006f5fc nbd: fix max number of supported devs
This fixes a bug added in 4.10 with commit:

commit 9561a7ade0
Author: Josef Bacik <jbacik@fb.com>
Date:   Tue Nov 22 14:04:40 2016 -0500

    nbd: add multi-connection support

that limited the number of devices to 256. Before the patch we could
create 1000s of devices, but the patch switched us from using our
own thread to using a work queue which has a default limit of 256
active works.

The problem is that our recv_work function sits in a loop until
disconnection but only handles IO for one connection. The work is
started when the connection is started/restarted, but if we end up
creating 257 or more connections, the queue_work call just queues
connection257+'s recv_work and that waits for connection 1 - 256's
recv_work to be disconnected and that work instance completing.

Instead of reverting back to kthreads, this has us allocate a
workqueue_struct per device, so we can block in the work.

Cc: stable@vger.kernel.org
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-20 12:44:07 -06:00
Mike Christie 2da22da573 nbd: fix zero cmd timeout handling v2
This fixes a regression added in 4.9 with commit:

commit 0eadf37afc
Author: Josef Bacik <jbacik@fb.com>
Date:   Thu Sep 8 12:33:40 2016 -0700

    nbd: allow block mq to deal with timeouts

where before the patch userspace would set the timeout to 0 to disable
it. With the above patch, a zero timeout tells the block layer to use
the default value of 30 seconds. For setups where commands can take a
long time or experience transient issues like network disruptions this
then results in IO errors being sent to the application.

To fix this, the patch still uses the common block layer timeout
framework, but if zero is set, nbd just logs a message and then resets
the timer when it expires.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-20 12:44:05 -06:00
Mike Christie 887e975c41 nbd: add missing config put
Fix bug added with the patch:

commit 8f3ea35929
Author: Josef Bacik <josef@toxicpanda.com>
Date:   Mon Jul 16 12:11:35 2018 -0400

    nbd: handle unexpected replies better

where if the timeout handler runs when the completion path is and we fail
to grab the mutex in the timeout handler we will leave a config reference
and cannot free the config later.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-20 12:44:04 -06:00
Mike Christie 00514677ed nbd: add function to convert blk req op to nbd cmd
This adds a helper function to convert a block req op to a nbd cmd type.
It will be used in the last patch to log the type in the timeout
handler.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-20 12:44:02 -06:00
Mike Christie 55313e92bd nbd: add set cmd timeout helper
Add a helper to set the cmd timeout. It does not really do a lot now,
but will be more useful in the next patches.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-20 12:44:01 -06:00
Munehisa Kamata 2b5c8f0063 nbd: replace kill_bdev() with __invalidate_device() again
Commit abbbdf1249 ("replace kill_bdev() with __invalidate_device()")
once did this, but 29eaadc036 ("nbd: stop using the bdev everywhere")
resurrected kill_bdev() and it has been there since then. So buffer_head
mappings still get killed on a server disconnection, and we can still
hit the BUG_ON on a filesystem on the top of the nbd device.

  EXT4-fs (nbd0): mounted filesystem with ordered data mode. Opts: (null)
  block nbd0: Receive control failed (result -32)
  block nbd0: shutting down sockets
  print_req_error: I/O error, dev nbd0, sector 66264 flags 3000
  EXT4-fs warning (device nbd0): htree_dirblock_to_tree:979: inode #2: lblock 0: comm ls: error -5 reading directory block
  print_req_error: I/O error, dev nbd0, sector 2264 flags 3000
  EXT4-fs error (device nbd0): __ext4_get_inode_loc:4690: inode #2: block 283: comm ls: unable to read itable block
  EXT4-fs error (device nbd0) in ext4_reserve_inode_write:5894: IO failure
  ------------[ cut here ]------------
  kernel BUG at fs/buffer.c:3057!
  invalid opcode: 0000 [#1] SMP PTI
  CPU: 7 PID: 40045 Comm: jbd2/nbd0-8 Not tainted 5.1.0-rc3+ #4
  Hardware name: Amazon EC2 m5.12xlarge/, BIOS 1.0 10/16/2017
  RIP: 0010:submit_bh_wbc+0x18b/0x190
  ...
  Call Trace:
   jbd2_write_superblock+0xf1/0x230 [jbd2]
   ? account_entity_enqueue+0xc5/0xf0
   jbd2_journal_update_sb_log_tail+0x94/0xe0 [jbd2]
   jbd2_journal_commit_transaction+0x12f/0x1d20 [jbd2]
   ? __switch_to_asm+0x40/0x70
   ...
   ? lock_timer_base+0x67/0x80
   kjournald2+0x121/0x360 [jbd2]
   ? remove_wait_queue+0x60/0x60
   kthread+0xf8/0x130
   ? commit_timeout+0x10/0x10 [jbd2]
   ? kthread_bind+0x10/0x10
   ret_from_fork+0x35/0x40

With __invalidate_device(), I no longer hit the BUG_ON with sync or
unmount on the disconnected device.

Fixes: 29eaadc036 ("nbd: stop using the bdev everywhere")
Cc: linux-block@vger.kernel.org
Cc: Ratna Manoj Bolla <manoj.br@gmail.com>
Cc: nbd@other.debian.org
Cc: stable@vger.kernel.org
Cc: David Woodhouse <dwmw@amazon.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Munehisa Kamata <kamatam@amazon.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-07-31 08:51:56 -06:00
Mike Christie 4ddeaae890 nbd: add netlink reconfigure resize support
If the device is setup with ioctl we can resize the device after the
initial setup, but if the device is setup with netlink we cannot use the
resize related ioctls and there is no netlink reconfigure size ATTR
handling code.

This patch adds netlink reconfigure resize support to match the ioctl
interface.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-07-10 21:21:31 -06:00
Xiubo Li 553768d116 nbd: fix crash when the blksize is zero
This will allow the blksize to be set zero and then use 1024 as
default.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
[fix to use goto out instead of return in genl_connect]
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-07-10 21:21:16 -06:00
Thomas Gleixner eb1fe3bfe8 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 127
Based on 1 normalized pattern(s):

  this file is released under gplv2 or later

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527063114.295960793@linutronix.de
Link: https://lkml.kernel.org/r/20190524100843.018830140@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:25:13 -07:00
David S. Miller 5f0d736e7f Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2019-04-28

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Introduce BPF socket local storage map so that BPF programs can store
   private data they associate with a socket (instead of e.g. separate hash
   table), from Martin.

2) Add support for bpftool to dump BTF types. This is done through a new
   `bpftool btf dump` sub-command, from Andrii.

3) Enable BPF-based flow dissector for skb-less eth_get_headlen() calls which
   was currently not supported since skb was used to lookup netns, from Stanislav.

4) Add an opt-in interface for tracepoints to expose a writable context
   for attached BPF programs, used here for NBD sockets, from Matt.

5) BPF xadd related arm64 JIT fixes and scalability improvements, from Daniel.

6) Change the skb->protocol for bpf_skb_adjust_room() helper in order to
   support tunnels such as sit. Add selftests as well, from Willem.

7) Various smaller misc fixes.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28 08:42:41 -04:00
Johannes Berg ef6243acb4 genetlink: optionally validate strictly/dumps
Add options to strictly validate messages and dump messages,
sometimes perhaps validating dump messages non-strictly may
be required, so add an option for that as well.

Since none of this can really be applied to existing commands,
set the options everwhere using the following spatch:

    @@
    identifier ops;
    expression X;
    @@
    struct genl_ops ops[] = {
    ...,
     {
            .cmd = X,
    +       .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
            ...
     },
    ...
    };

For new commands one should just not copy the .validate 'opt-out'
flags and thus get strict validation.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27 17:07:22 -04:00
Johannes Berg 8cb081746c netlink: make validation more configurable for future strictness
We currently have two levels of strict validation:

 1) liberal (default)
     - undefined (type >= max) & NLA_UNSPEC attributes accepted
     - attribute length >= expected accepted
     - garbage at end of message accepted
 2) strict (opt-in)
     - NLA_UNSPEC attributes accepted
     - attribute length >= expected accepted

Split out parsing strictness into four different options:
 * TRAILING     - check that there's no trailing data after parsing
                  attributes (in message or nested)
 * MAXTYPE      - reject attrs > max known type
 * UNSPEC       - reject attributes with NLA_UNSPEC policy entries
 * STRICT_ATTRS - strictly validate attribute size

The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().

Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.

We end up with the following renames:
 * nla_parse           -> nla_parse_deprecated
 * nla_parse_strict    -> nla_parse_deprecated_strict
 * nlmsg_parse         -> nlmsg_parse_deprecated
 * nlmsg_parse_strict  -> nlmsg_parse_deprecated_strict
 * nla_parse_nested    -> nla_parse_nested_deprecated
 * nla_validate_nested -> nla_validate_nested_deprecated

Using spatch, of course:
    @@
    expression TB, MAX, HEAD, LEN, POL, EXT;
    @@
    -nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
    +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)

    @@
    expression NLH, HDRLEN, TB, MAX, POL, EXT;
    @@
    -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
    +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)

    @@
    expression NLH, HDRLEN, TB, MAX, POL, EXT;
    @@
    -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
    +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)

    @@
    expression TB, MAX, NLA, POL, EXT;
    @@
    -nla_parse_nested(TB, MAX, NLA, POL, EXT)
    +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)

    @@
    expression START, MAX, POL, EXT;
    @@
    -nla_validate_nested(START, MAX, POL, EXT)
    +nla_validate_nested_deprecated(START, MAX, POL, EXT)

    @@
    expression NLH, HDRLEN, MAX, POL, EXT;
    @@
    -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
    +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)

For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.

Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.

Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.

In effect then, this adds fully strict validation for any new command.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27 17:07:21 -04:00
Michal Kubecek ae0be8de9a netlink: make nla_nest_start() add NLA_F_NESTED flag
Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most
netlink based interfaces (including recently added ones) are still not
setting it in kernel generated messages. Without the flag, message parsers
not aware of attribute semantics (e.g. wireshark dissector or libmnl's
mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display
the structure of their contents.

Unfortunately we cannot just add the flag everywhere as there may be
userspace applications which check nlattr::nla_type directly rather than
through a helper masking out the flags. Therefore the patch renames
nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start()
as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually
are rewritten to use nla_nest_start().

Except for changes in include/net/netlink.h, the patch was generated using
this semantic patch:

@@ expression E1, E2; @@
-nla_nest_start(E1, E2)
+nla_nest_start_noflag(E1, E2)

@@ expression E1, E2; @@
-nla_nest_start_noflag(E1, E2 | NLA_F_NESTED)
+nla_nest_start(E1, E2)

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27 17:03:44 -04:00
Andrew Hall 2abd2de712 nbd: add tracepoints for send/receive timing
This adds four tracepoints to nbd, enabling separate tracing of payload
and header sending/receipt.

In the send path for headers that have already been sent, we also
explicitly initialize the handle so it can be referenced by the later
tracepoint.

Signed-off-by: Andrew Hall <hall@fb.com>
Signed-off-by: Matt Mullins <mmullins@fb.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-26 19:04:19 -07:00
Matt Mullins ea106722c7 nbd: trace sending nbd requests
This adds a tracepoint that can both observe the nbd request being sent
to the server, as well as modify that request , e.g., setting a flag in
the request that will cause the server to collect detailed tracing data.

The struct request * being handled is included to permit correlation
with the block tracepoints.

Signed-off-by: Matt Mullins <mmullins@fb.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-26 19:04:19 -07:00
Johannes Berg 3b0f31f2b8 genetlink: make policy common to family
Since maxattr is common, the policy can't really differ sanely,
so make it common as well.

The only user that did in fact manage to make a non-common policy
is taskstats, which has to be really careful about it (since it's
still using a common maxattr!). This is no longer supported, but
we can fake it using pre_doit.

This reduces the size of e.g. nl80211.o (which has lots of commands):

   text	   data	    bss	    dec	    hex	filename
 398745	  14323	   2240	 415308	  6564c	net/wireless/nl80211.o (before)
 397913	  14331	   2240	 414484	  65314	net/wireless/nl80211.o (after)
--------------------------------
   -832      +8       0    -824

Which is obviously just 8 bytes for each command, and an added 8
bytes for the new policy pointer. I'm not sure why the ops list is
counted as .text though.

Most of the code transformations were done using the following spatch:
    @ops@
    identifier OPS;
    expression POLICY;
    @@
    struct genl_ops OPS[] = {
    ...,
     {
    -	.policy = POLICY,
     },
    ...
    };

    @@
    identifier ops.OPS;
    expression ops.POLICY;
    identifier fam;
    expression M;
    @@
    struct genl_family fam = {
            .ops = OPS,
            .maxattr = M,
    +       .policy = POLICY,
            ...
    };

This also gets rid of devlink_nl_cmd_region_read_dumpit() accessing
the cb->data as ops, which we want to change in a later genl patch.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-22 10:38:23 -04:00
Li RongQing cd46eb89df nbd: propagate genlmsg_reply return code
genlmsg_reply can fail, so propagate its return code

Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-28 14:06:37 -07:00
Ming Lei 56d18f62f5 block: kill BLK_MQ_F_SG_MERGE
QUEUE_FLAG_NO_SG_MERGE has been killed, so kill BLK_MQ_F_SG_MERGE too.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-15 08:40:12 -07:00
Jan Kara c8a83a6b54 nbd: Use set_blocksize() to set device blocksize
NBD can update block device block size implicitely through
bd_set_size(). Make it explicitely set blocksize with set_blocksize() as
this behavior of bd_set_size() is going away.

CC: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-01-15 07:30:54 -07:00
Jens Axboe 7baa85727d blk-mq-tag: change busy_iter_fn to return whether to continue or not
We have this functionality in sbitmap, but we don't export it in
blk-mq for users of the tags busy iteration. This can be useful
for stopping the iteration, if the caller doesn't need to find
more requests.

Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 10:24:07 -07:00
David Howells aa563d7bca iov_iter: Separate type from direction and use accessor functions
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:07 +01:00
Jens Axboe bc811f05d7 nbd: don't allow invalid blocksize settings
syzbot reports a divide-by-zero off the NBD_SET_BLKSIZE ioctl.
We need proper validation of the input here. Not just if it's
zero, but also if the value is a power-of-2 and in a valid
range. Add that.

Cc: stable@vger.kernel.org
Reported-by: syzbot <syzbot+25dbecbec1e62c6b0dd4@syzkaller.appspotmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-04 11:54:58 -06:00
David S. Miller 89b1698c93 Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net
The BTF conflicts were simple overlapping changes.

The virtio_net conflict was an overlap of a fix of statistics counter,
happening alongisde a move over to a bonafide statistics structure
rather than counting value on the stack.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-02 10:55:32 -07:00
Stephen Hemminger a86c412052 nbd: constify nla_policy
The netlink policy should be const like other drivers.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-20 12:33:37 -07:00
Josef Bacik 8f3ea35929 nbd: handle unexpected replies better
If the server or network is misbehaving and we get an unexpected reply
we can sometimes miss the request not being started and wait on a
request and never get a response, or even double complete the same
request.  Fix this by replacing the send_complete completion with just a
per command lock.  Add a per command cookie as well so that we can know
if we're getting a double completion for a previous event.  Also check
to make sure we dont have REQUEUED set as that means we raced with the
timeout handler and need to just let the retry occur.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-16 10:14:40 -06:00
Josef Bacik d7d94d48a2 nbd: don't requeue the same request twice.
We can race with the snd timeout and the per-request timeout and end up
requeuing the same request twice.  We can't use the send_complete
completion to tell if everything is ok because we hold the tx_lock
during send, so the timeout stuff will block waiting to mark the socket
dead, and we could be marked complete and still requeue.  Instead add a
flag to the socket so we know whether we've been requeued yet.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-16 10:14:39 -06:00
Doron Roberts-Kedes 08ba91ee6e nbd: Add the nbd NBD_DISCONNECT_ON_CLOSE config flag.
If NBD_DISCONNECT_ON_CLOSE is set on a device, then the driver will
issue a disconnect from nbd_release if the device has no remaining
bdev->bd_openers.

Fix ret val so reconfigure with only setting the flag succeeds.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Doron Roberts-Kedes <doronrk@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-20 19:10:06 -06:00
Josef Bacik 07ce213f63 nbd: set discard_alignment to the granularity
Technically we should be able to get away with 0 as the
discard_alignment, but there's no way currently for the protocol to
indicate different alignments, and in real life most disks have
discard_alignment == discard_granularity.  Just set our alignment to our
blocksize to make sure discards will actually work properly with 4k
drives.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-05 09:50:46 -06:00
Kevin Vigor ee57a05cf8 nbd: Consistently use request pointer in debug messages.
Existing dev_dbg messages sometimes identify request using request
pointer, sometimes using nbd_cmd pointer. This makes it hard to
follow request flow. Consistently use request pointer instead.

Reviewed-by: Josef Bacik <jbacik@toxicpanda.com>
Signed-off-by: Kevin Vigor <kvigor@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-05 09:45:01 -06:00
Christoph Hellwig d250bf4e77 blk-mq: only iterate over inflight requests in blk_mq_tagset_busy_iter
We already check for started commands in all callbacks, but we should
also protect against already completed commands.  Do this by taking
the checks to common code.

Acked-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-30 11:31:34 -06:00
Kevin Vigor 5e3c3a7ece nbd: clear DISCONNECT_REQUESTED flag once disconnection occurs.
When a userspace client requests a NBD device be disconnected, the
DISCONNECT_REQUESTED flag is set. While this flag is set, the driver
will not inform userspace when a connection is closed.

Unfortunately the flag was never cleared, so once a disconnect was
requested the driver would thereafter never tell userspace about a
closed connection. Thus when connections failed due to timeout, no
attempt to reconnect was made and eventually the device would fail.

Fix by clearing the DISCONNECT_REQUESTED flag (and setting the
DISCONNECTED flag) once all connections are closed.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Kevin Vigor <kvigor@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-30 11:30:42 -06:00
Christoph Hellwig e5eab01704 nbd: complete requests from ->timeout
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig 6600593cbd block: rename BLK_EH_NOT_HANDLED to BLK_EH_DONE
The BLK_EH_NOT_HANDLED implies nothing happen, but very often that
is not what is happening - instead the driver already completed the
command.  Fix the symbolic name to reflect that a little better.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Joe Perches 5657a819a8 block drivers/block: Use octal not symbolic permissions
Convert the S_<FOO> symbolic permissions to their octal equivalents as
using octal and not symbolic permissions is preferred by many as more
readable.

see: https://lkml.org/lkml/2016/8/2/1945

Done with automated conversion via:
$ ./scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace <files...>

Miscellanea:

o Wrapped modified multi-line calls to a single line where appropriate
o Realign modified multi-line calls to open parenthesis

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-24 13:38:59 -06:00
Josef Bacik 6df133a149 nbd: set discard granularity properly
For some reason we had discard granularity set to 512 always even when
discards were disabled.  Fix this by having the default be 0, and then
if we turn it on set the discard granularity to the blocksize.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-23 15:27:26 -06:00