Commit Graph

55981 Commits

Author SHA1 Message Date
Oleg Nesterov
ab5f740712 exec: load_script: don't blindly truncate shebang string
[ Upstream commit 8099b047ec ]

load_script() simply truncates bprm->buf and this is very wrong if the
length of shebang string exceeds BINPRM_BUF_SIZE-2.  This can silently
truncate i_arg or (worse) we can execute the wrong binary if buf[2:126]
happens to be the valid executable path.

Change load_script() to return ENOEXEC if it can't find '\n' or zero in
bprm->buf.  Note that '\0' can come from either
prepare_binprm()->memset() or from kernel_read(), we do not care.

Link: http://lkml.kernel.org/r/20181112160931.GA28463@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Ben Woodard <woodard@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
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>
2019-02-12 19:47:20 +01:00
Davidlohr Bueso
9cb8f8088d fs/epoll: drop ovflist branch prediction
[ Upstream commit 76699a67f3 ]

The ep->ovflist is a secondary ready-list to temporarily store events
that might occur when doing sproc without holding the ep->wq.lock.  This
accounts for every time we check for ready events and also send events
back to userspace; both callbacks, particularly the latter because of
copy_to_user, can account for a non-trivial time.

As such, the unlikely() check to see if the pointer is being used, seems
both misleading and sub-optimal.  In fact, we go to an awful lot of
trouble to sync both lists, and populating the ovflist is far from an
uncommon scenario.

For example, profiling a concurrent epoll_wait(2) benchmark, with
CONFIG_PROFILE_ANNOTATED_BRANCHES shows that for a two threads a 33%
incorrect rate was seen; and when incrementally increasing the number of
epoll instances (which is used, for example for multiple queuing load
balancing models), up to a 90% incorrect rate was seen.

Similarly, by deleting the prediction, 3% throughput boost was seen
across incremental threads.

Link: http://lkml.kernel.org/r/20181108051006.18751-4-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jason Baron <jbaron@akamai.com>
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>
2019-02-12 19:47:19 +01:00
Larry Chen
066206bc6e ocfs2: improve ocfs2 Makefile
[ Upstream commit 9e6aea2280 ]

Included file path was hard-wired in the ocfs2 makefile, which might
causes some confusion when compiling ocfs2 as an external module.

Say if we compile ocfs2 module as following.
cp -r /kernel/tree/fs/ocfs2 /other/dir/ocfs2
cd /other/dir/ocfs2
make -C /path/to/kernel_source M=`pwd` modules

Acutally, the compiler wil try to find included file in
/kernel/tree/fs/ocfs2, rather than the directory /other/dir/ocfs2.

To fix this little bug, we introduce the var $(src) provided by kbuild.
$(src) means the absolute path of the running kbuild file.

Link: http://lkml.kernel.org/r/20181108085546.15149-1-lchen@suse.com
Signed-off-by: Larry Chen <lchen@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <ge.changwei@h3c.com>
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>
2019-02-12 19:47:18 +01:00
Junxiao Bi
69e63b49dd ocfs2: don't clear bh uptodate for block read
[ Upstream commit 70306d9dce ]

For sync io read in ocfs2_read_blocks_sync(), first clear bh uptodate flag
and submit the io, second wait io done, last check whether bh uptodate, if
not return io error.

If two sync io for the same bh were issued, it could be the first io done
and set uptodate flag, but just before check that flag, the second io came
in and cleared uptodate, then ocfs2_read_blocks_sync() for the first io
will return IO error.

Indeed it's not necessary to clear uptodate flag, as the io end handler
end_buffer_read_sync() will set or clear it based on io succeed or failed.

The following message was found from a nfs server but the underlying
storage returned no error.

[4106438.567376] (nfsd,7146,3):ocfs2_get_suballoc_slot_bit:2780 ERROR: read block 1238823695 failed -5
[4106438.567569] (nfsd,7146,3):ocfs2_get_suballoc_slot_bit:2812 ERROR: status = -5
[4106438.567611] (nfsd,7146,3):ocfs2_test_inode_bit:2894 ERROR: get alloc slot and bit failed -5
[4106438.567643] (nfsd,7146,3):ocfs2_test_inode_bit:2932 ERROR: status = -5
[4106438.567675] (nfsd,7146,3):ocfs2_get_dentry:94 ERROR: test inode bit failed -5

Same issue in non sync read ocfs2_read_blocks(), fixed it as well.

Link: http://lkml.kernel.org/r/20181121020023.3034-4-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Changwei Ge <ge.changwei@h3c.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mfasheh@versity.com>
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>
2019-02-12 19:47:18 +01:00
Sahitya Tummala
df13b0369b f2fs: fix sbi->extent_list corruption issue
[ Upstream commit e4589fa545 ]

When there is a failure in f2fs_fill_super() after/during
the recovery of fsync'd nodes, it frees the current sbi and
retries again. This time the mount is successful, but the files
that got recovered before retry, still holds the extent tree,
whose extent nodes list is corrupted since sbi and sbi->extent_list
is freed up. The list_del corruption issue is observed when the
file system is getting unmounted and when those recoverd files extent
node is being freed up in the below context.

list_del corruption. prev->next should be fffffff1e1ef5480, but was (null)
<...>
kernel BUG at kernel/msm-4.14/lib/list_debug.c:53!
lr : __list_del_entry_valid+0x94/0xb4
pc : __list_del_entry_valid+0x94/0xb4
<...>
Call trace:
__list_del_entry_valid+0x94/0xb4
__release_extent_node+0xb0/0x114
__free_extent_tree+0x58/0x7c
f2fs_shrink_extent_tree+0xdc/0x3b0
f2fs_leave_shrinker+0x28/0x7c
f2fs_put_super+0xfc/0x1e0
generic_shutdown_super+0x70/0xf4
kill_block_super+0x2c/0x5c
kill_f2fs_super+0x44/0x50
deactivate_locked_super+0x60/0x8c
deactivate_super+0x68/0x74
cleanup_mnt+0x40/0x78
__cleanup_mnt+0x1c/0x28
task_work_run+0x48/0xd0
do_notify_resume+0x678/0xe98
work_pending+0x8/0x14

Fix this by not creating extents for those recovered files if shrinker is
not registered yet. Once mount is successful and shrinker is registered,
those files can have extents again.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:17 +01:00
Sahitya Tummala
69e7f87745 f2fs: fix use-after-free issue when accessing sbi->stat_info
[ Upstream commit 60aa4d5536 ]

iput() on sbi->node_inode can update sbi->stat_info
in the below context, if the f2fs_write_checkpoint()
has failed with error.

f2fs_balance_fs_bg+0x1ac/0x1ec
f2fs_write_node_pages+0x4c/0x260
do_writepages+0x80/0xbc
__writeback_single_inode+0xdc/0x4ac
writeback_single_inode+0x9c/0x144
write_inode_now+0xc4/0xec
iput+0x194/0x22c
f2fs_put_super+0x11c/0x1e8
generic_shutdown_super+0x70/0xf4
kill_block_super+0x2c/0x5c
kill_f2fs_super+0x44/0x50
deactivate_locked_super+0x60/0x8c
deactivate_super+0x68/0x74
cleanup_mnt+0x40/0x78

Fix this by moving f2fs_destroy_stats() further below iput() in
both f2fs_put_super() and f2fs_fill_super() paths.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:17 +01:00
Ronnie Sahlberg
5d3b4cd873 cifs: check ntwrk_buf_start for NULL before dereferencing it
[ Upstream commit 59a63e479c ]

RHBZ: 1021460

There is an issue where when multiple threads open/close the same directory
ntwrk_buf_start might end up being NULL, causing the call to smbCalcSize
later to oops with a NULL deref.

The real bug is why this happens and why this can become NULL for an
open cfile, which should not be allowed.
This patch tries to avoid a oops until the time when we fix the underlying
issue.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:17 +01:00
Chris Perl
8c642d7190 NFS: nfs_compare_mount_options always compare auth flavors.
[ Upstream commit 594d1644cd ]

This patch removes the check from nfs_compare_mount_options to see if a
`sec' option was passed for the current mount before comparing auth
flavors and instead just always compares auth flavors.

Consider the following scenario:

You have a server with the address 192.168.1.1 and two exports /export/a
and /export/b.  The first export supports `sys' and `krb5' security, the
second just `sys'.

Assume you start with no mounts from the server.

The following results in EIOs being returned as the kernel nfs client
incorrectly thinks it can share the underlying `struct nfs_server's:

$ mkdir /tmp/{a,b}
$ sudo mount -t nfs -o vers=3,sec=krb5 192.168.1.1:/export/a /tmp/a
$ sudo mount -t nfs -o vers=3          192.168.1.1:/export/b /tmp/b
$ df >/dev/null
df: ‘/tmp/b’: Input/output error

Signed-off-by: Chris Perl <cperl@janestreet.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:16 +01:00
Ethan Lien
f5d5b54349 btrfs: use tagged writepage to mitigate livelock of snapshot
[ Upstream commit 3cd24c6980 ]

Snapshot is expected to be fast. But if there are writers steadily
creating dirty pages in our subvolume, the snapshot may take a very long
time to complete. To fix the problem, we use tagged writepage for
snapshot flusher as we do in the generic write_cache_pages(), so we can
omit pages dirtied after the snapshot command.

This does not change the semantics regarding which data get to the
snapshot, if there are pages being dirtied during the snapshotting
operation.  There's a sync called before snapshot is taken in old/new
case, any IO in flight just after that may be in the snapshot but this
depends on other system effects that might still sync the IO.

We do a simple snapshot speed test on a Intel D-1531 box:

fio --ioengine=libaio --iodepth=32 --bs=4k --rw=write --size=64G
--direct=0 --thread=1 --numjobs=1 --time_based --runtime=120
--filename=/mnt/sub/testfile --name=job1 --group_reporting & sleep 5;
time btrfs sub snap -r /mnt/sub /mnt/snap; killall fio

original: 1m58sec
patched:  6.54sec

This is the best case for this patch since for a sequential write case,
we omit nearly all pages dirtied after the snapshot command.

For a multi writers, random write test:

fio --ioengine=libaio --iodepth=32 --bs=4k --rw=randwrite --size=64G
--direct=0 --thread=1 --numjobs=4 --time_based --runtime=120
--filename=/mnt/sub/testfile --name=job1 --group_reporting & sleep 5;
time btrfs sub snap -r /mnt/sub /mnt/snap; killall fio

original: 15.83sec
patched:  10.35sec

The improvement is smaller compared to the sequential write case,
since we omit only half of the pages dirtied after snapshot command.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:11 +01:00
Anand Jain
3733632e8b btrfs: harden agaist duplicate fsid on scanned devices
[ Upstream commit a9261d4125 ]

It's not that impossible to imagine that a device OR a btrfs image is
copied just by using the dd or the cp command. Which in case both the
copies of the btrfs will have the same fsid. If on the system with
automount enabled, the copied FS gets scanned.

We have a known bug in btrfs, that we let the device path be changed
after the device has been mounted. So using this loop hole the new
copied device would appears as if its mounted immediately after it's
been copied.

For example:

Initially.. /dev/mmcblk0p4 is mounted as /

  $ lsblk
  NAME        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
  mmcblk0     179:0    0 29.2G  0 disk
  |-mmcblk0p4 179:4    0    4G  0 part /
  |-mmcblk0p2 179:2    0  500M  0 part /boot
  |-mmcblk0p3 179:3    0  256M  0 part [SWAP]
  `-mmcblk0p1 179:1    0  256M  0 part /boot/efi

  $ btrfs fi show
     Label: none  uuid: 07892354-ddaa-4443-90ea-f76a06accaba
     Total devices 1 FS bytes used 1.40GiB
     devid    1 size 4.00GiB used 3.00GiB path /dev/mmcblk0p4

Copy mmcblk0 to sda

  $ dd if=/dev/mmcblk0 of=/dev/sda

And immediately after the copy completes the change in the device
superblock is notified which the automount scans using btrfs device scan
and the new device sda becomes the mounted root device.

  $ lsblk
  NAME        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
  sda           8:0    1 14.9G  0 disk
  |-sda4        8:4    1    4G  0 part /
  |-sda2        8:2    1  500M  0 part
  |-sda3        8:3    1  256M  0 part
  `-sda1        8:1    1  256M  0 part
  mmcblk0     179:0    0 29.2G  0 disk
  |-mmcblk0p4 179:4    0    4G  0 part
  |-mmcblk0p2 179:2    0  500M  0 part /boot
  |-mmcblk0p3 179:3    0  256M  0 part [SWAP]
  `-mmcblk0p1 179:1    0  256M  0 part /boot/efi

  $ btrfs fi show /
    Label: none  uuid: 07892354-ddaa-4443-90ea-f76a06accaba
    Total devices 1 FS bytes used 1.40GiB
    devid    1 size 4.00GiB used 3.00GiB path /dev/sda4

The bug is quite nasty that you can't either unmount /dev/sda4 or
/dev/mmcblk0p4. And the problem does not get solved until you take sda
out of the system on to another system to change its fsid using the
'btrfstune -u' command.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:10 +01:00
Jan Kara
6a1d712b43 udf: Fix BUG on corrupted inode
[ Upstream commit d288d95842 ]

When inode is corrupted so that extent type is invalid, some functions
(such as udf_truncate_extents()) will just BUG. Check that extent type
is valid when loading the inode to memory.

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:09 +01:00
J. Bruce Fields
2f0fb76b3e nfsd4: fix crash on writing v4_end_grace before nfsd startup
[ Upstream commit 62a063b8e7 ]

Anatoly Trosinenko reports that this:

1) Checkout fresh master Linux branch (tested with commit e195ca6cb)
2) Copy x84_64-config-4.14 to .config, then enable NFS server v4 and build
3) From `kvm-xfstests shell`:

results in NULL dereference in locks_end_grace.

Check that nfsd has been started before trying to end the grace period.

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:03 +01:00
Tiezhu Yang
d54d612a73 f2fs: fix wrong return value of f2fs_acl_create
[ Upstream commit f6176473a0 ]

When call f2fs_acl_create_masq() failed, the caller f2fs_acl_create()
should return -EIO instead of -ENOMEM, this patch makes it consistent
with posix_acl_create() which has been fixed in commit beaf226b86
("posix_acl: don't ignore return value of posix_acl_create_masq()").

Fixes: 83dfe53c18 ("f2fs: fix reference leaks in f2fs_acl_create")
Signed-off-by: Tiezhu Yang <kernelpatch@126.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:02 +01:00
Sheng Yong
ddab3d0a38 f2fs: fix race between write_checkpoint and write_begin
[ Upstream commit 2866fb16d6 ]

The following race could lead to inconsistent SIT bitmap:

Task A                          Task B
======                          ======
f2fs_write_checkpoint
  block_operations
    f2fs_lock_all
      down_write(node_change)
      down_write(node_write)
      ... sync ...
      up_write(node_change)
                                f2fs_file_write_iter
                                  set_inode_flag(FI_NO_PREALLOC)
                                  ......
                                  f2fs_write_begin(index=0, has inline data)
                                    prepare_write_begin
                                      __do_map_lock(AIO) => down_read(node_change)
                                      f2fs_convert_inline_page => update SIT
                                      __do_map_lock(AIO) => up_read(node_change)
  f2fs_flush_sit_entries <= inconsistent SIT
  finish write checkpoint
  sudden-power-off

If SPO occurs after checkpoint is finished, SIT bitmap will be set
incorrectly.

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:02 +01:00
Yunlei He
c96d2b9d35 f2fs: move dir data flush to write checkpoint process
[ Upstream commit b61ac5b720 ]

This patch move dir data flush to write checkpoint process, by
doing this, it may reduce some time for dir fsync.

pre:
	-f2fs_do_sync_file enter
		-file_write_and_wait_range  <- flush & wait
		-write_checkpoint
			-do_checkpoint	    <- wait all
	-f2fs_do_sync_file exit

now:
	-f2fs_do_sync_file enter
		-write_checkpoint
			-block_operations   <- flush dir & no wait
			-do_checkpoint	    <- wait all
	-f2fs_do_sync_file exit

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:02 +01:00
Bob Peterson
ee9268a9b5 dlm: Don't swamp the CPU with callbacks queued during recovery
[ Upstream commit 216f0efd19 ]

Before this patch, recovery would cause all callbacks to be delayed,
put on a queue, and afterward they were all queued to the callback
work queue. This patch does the same thing, but occasionally takes
a break after 25 of them so it won't swamp the CPU at the expense
of other RT processes like corosync.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:46:58 +01:00
Paulo Alcantara
c0be624777 cifs: Always resolve hostname before reconnecting
commit 28eb24ff75 upstream.

In case a hostname resolves to a different IP address (e.g. long
running mounts), make sure to resolve it every time prior to calling
generic_ip_connect() in reconnect.

Suggested-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:16 +01:00
Eric W. Biederman
9ee5987f31 btrfs: On error always free subvol_name in btrfs_mount
commit 532b618bdf upstream.

The subvol_name is allocated in btrfs_parse_subvol_options and is
consumed and freed in mount_subvol.  Add a free to the error paths that
don't call mount_subvol so that it is guaranteed that subvol_name is
freed when an error happens.

Fixes: 312c89fbca ("btrfs: cleanup btrfs_mount() using btrfs_mount_root()")
Cc: stable@vger.kernel.org # v4.19+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:14 +01:00
Filipe Manana
5bce143671 Btrfs: fix deadlock when allocating tree block during leaf/node split
commit a627947076 upstream.

When splitting a leaf or node from one of the trees that are modified when
flushing pending block groups (extent, chunk, device and free space trees),
we need to allocate a new tree block, which in turn can result in the need
to allocate a new block group. After allocating the new block group we may
need to flush new block groups that were previously allocated during the
course of the current transaction, which is what may cause a deadlock due
to attempts to write lock twice the same leaf or node, as when splitting
a leaf or node we are holding a write lock on it and its parent node.

The same type of deadlock can also happen when increasing the tree's
height, since we are holding a lock on the existing root while allocating
the tree block to use as the new root node.

An example trace when the deadlock happens during the leaf split path is:

  [27175.293054] CPU: 0 PID: 3005 Comm: kworker/u17:6 Tainted: G        W         4.19.16 #1
  [27175.293942] Hardware name: Penguin Computing Relion 1900/MD90-FS0-ZB-XX, BIOS R15 06/25/2018
  [27175.294846] Workqueue: btrfs-extent-refs btrfs_extent_refs_helper [btrfs]
  (...)
  [27175.298384] RSP: 0018:ffffab2087107758 EFLAGS: 00010246
  [27175.299269] RAX: 0000000000000bbd RBX: ffff9fadc7141c48 RCX: 0000000000000001
  [27175.300155] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9fadc7141c48
  [27175.301023] RBP: 0000000000000001 R08: ffff9faeb6ac1040 R09: ffff9fa9c0000000
  [27175.301887] R10: 0000000000000000 R11: 0000000000000040 R12: ffff9fb21aac8000
  [27175.302743] R13: ffff9fb1a64d6a20 R14: 0000000000000001 R15: ffff9fb1a64d6a18
  [27175.303601] FS:  0000000000000000(0000) GS:ffff9fb21fa00000(0000) knlGS:0000000000000000
  [27175.304468] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [27175.305339] CR2: 00007fdc8743ead8 CR3: 0000000763e0a006 CR4: 00000000003606f0
  [27175.306220] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [27175.307087] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [27175.307940] Call Trace:
  [27175.308802]  btrfs_search_slot+0x779/0x9a0 [btrfs]
  [27175.309669]  ? update_space_info+0xba/0xe0 [btrfs]
  [27175.310534]  btrfs_insert_empty_items+0x67/0xc0 [btrfs]
  [27175.311397]  btrfs_insert_item+0x60/0xd0 [btrfs]
  [27175.312253]  btrfs_create_pending_block_groups+0xee/0x210 [btrfs]
  [27175.313116]  do_chunk_alloc+0x25f/0x300 [btrfs]
  [27175.313984]  find_free_extent+0x706/0x10d0 [btrfs]
  [27175.314855]  btrfs_reserve_extent+0x9b/0x1d0 [btrfs]
  [27175.315707]  btrfs_alloc_tree_block+0x100/0x5b0 [btrfs]
  [27175.316548]  split_leaf+0x130/0x610 [btrfs]
  [27175.317390]  btrfs_search_slot+0x94d/0x9a0 [btrfs]
  [27175.318235]  btrfs_insert_empty_items+0x67/0xc0 [btrfs]
  [27175.319087]  alloc_reserved_file_extent+0x84/0x2c0 [btrfs]
  [27175.319938]  __btrfs_run_delayed_refs+0x596/0x1150 [btrfs]
  [27175.320792]  btrfs_run_delayed_refs+0xed/0x1b0 [btrfs]
  [27175.321643]  delayed_ref_async_start+0x81/0x90 [btrfs]
  [27175.322491]  normal_work_helper+0xd0/0x320 [btrfs]
  [27175.323328]  ? move_linked_works+0x6e/0xa0
  [27175.324160]  process_one_work+0x191/0x370
  [27175.324976]  worker_thread+0x4f/0x3b0
  [27175.325763]  kthread+0xf8/0x130
  [27175.326531]  ? rescuer_thread+0x320/0x320
  [27175.327284]  ? kthread_create_worker_on_cpu+0x50/0x50
  [27175.328027]  ret_from_fork+0x35/0x40
  [27175.328741] ---[ end trace 300a1b9f0ac30e26 ]---

Fix this by preventing the flushing of new blocks groups when splitting a
leaf/node and when inserting a new root node for one of the trees modified
by the flushing operation, similar to what is done when COWing a node/leaf
from on of these trees.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202383
Reported-by: Eli V <eliventer@gmail.com>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:14 +01:00
Andreas Gruenbacher
8b9be9db8a gfs2: Revert "Fix loop in gfs2_rbm_find"
commit e74c98ca2d upstream.

This reverts commit 2d29f6b96d.

It turns out that the fix can lead to a ~20 percent performance regression
in initial writes to the page cache according to iozone.  Let's revert this
for now to have more time for a proper fix.

Cc: stable@vger.kernel.org # v3.13+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:13 +01:00
Trond Myklebust
0a3275d785 NFS: Fix up return value on fatal errors in nfs_page_async_flush()
commit 8fc75bed96 upstream.

Ensure that we return the fatal error value that caused us to exit
nfs_page_async_flush().

Fixes: c373fff7bd ("NFSv4: Don't special case "launder"")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.12+
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:11 +01:00
Waiman Long
bb4e1ff5a8 fs/dcache: Fix incorrect nr_dentry_unused accounting in shrink_dcache_sb()
commit 1dbd449c99 upstream.

The nr_dentry_unused per-cpu counter tracks dentries in both the LRU
lists and the shrink lists where the DCACHE_LRU_LIST bit is set.

The shrink_dcache_sb() function moves dentries from the LRU list to a
shrink list and subtracts the dentry count from nr_dentry_unused.  This
is incorrect as the nr_dentry_unused count will also be decremented in
shrink_dentry_list() via d_shrink_del().

To fix this double decrement, the decrement in the shrink_dcache_sb()
function is taken out.

Fixes: 4e717f5c10 ("list_lru: remove special case function list_lru_dispose_all."
Cc: stable@kernel.org
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:11 +01:00
Pavel Shilovsky
e9d56f920b CIFS: Do not consider -ENODATA as stat failure for reads
commit 082aaa8700 upstream.

When doing reads beyound the end of a file the server returns
error STATUS_END_OF_FILE error which is mapped to -ENODATA.
Currently we report it as a failure which confuses read stats.
Change it to not consider -ENODATA as failure for stat purposes.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:11 +01:00
Pavel Shilovsky
6e7045ec33 CIFS: Fix trace command logging for SMB2 reads and writes
commit 7d42e72fe8 upstream.

Currently we log success once we send an async IO request to
the server. Instead we need to analyse a response and then log
success or failure for a particular command. Also fix argument
list for read logging.

Cc: <stable@vger.kernel.org> # 4.18
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:11 +01:00
Pavel Shilovsky
c6961288a5 CIFS: Do not count -ENODATA as failure for query directory
commit 8e6e72aece upstream.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:11 +01:00
Ronnie Sahlberg
06d9f98720 smb3: add credits we receive from oplock/break PDUs
commit 2e5700bdde upstream.

Otherwise we gradually leak credits leading to potential
hung session.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Pavel Shilovsky
779c65bb77 CIFS: Do not reconnect TCP session in add_credits()
commit ef68e83184 upstream.

When executing add_credits() we currently call cifs_reconnect()
if the number of credits is zero and there are no requests in
flight. In this case we may call cifs_reconnect() recursively
twice and cause memory corruption given the following sequence
of functions:

mid1.callback() -> add_credits() -> cifs_reconnect() ->
-> mid2.callback() -> add_credits() -> cifs_reconnect().

Fix this by avoiding to call cifs_reconnect() in add_credits()
and checking for zero credits in the demultiplex thread.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Pavel Shilovsky
2ae6fedbd5 CIFS: Fix credit calculation for encrypted reads with errors
commit ec678eae74 upstream.

We do need to account for credits received in error responses
to read requests on encrypted sessions.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Pavel Shilovsky
0380ed9b1c CIFS: Fix credits calculations for reads with errors
commit 8004c78c68 upstream.

Currently we mark MID as malformed if we get an error from server
in a read response. This leads to not properly processing credits
in the readv callback. Fix this by marking such a response as
normal received response and process it appropriately.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Pavel Shilovsky
07b9e5e35e CIFS: Fix possible hang during async MTU reads and writes
commit acc58d0bab upstream.

When doing MTU i/o we need to leave some credits for
possible reopen requests and other operations happening
in parallel. Currently we leave 1 credit which is not
enough even for reopen only: we need at least 2 credits
if durable handle reconnect fails. Also there may be
other operations at the same time including compounding
ones which require 3 credits at a time each. Fix this
by leaving 8 credits which is big enough to cover most
scenarios.

Was able to reproduce this when server was configured
to give out fewer credits than usual.

The proper fix would be to reconnect a file handle first
and then obtain credits for an MTU request but this leads
to bigger code changes and should happen in other patches.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Tetsuo Handa
a719cbe078 inotify: Fix fd refcount leak in inotify_add_watch().
commit 125892edfe upstream.

Commit 4d97f7d53d ("inotify: Add flag IN_MASK_CREATE for
inotify_add_watch()") forgot to call fdput() before bailing out.

Fixes: 4d97f7d53d ("inotify: Add flag IN_MASK_CREATE for inotify_add_watch()")
CC: stable@vger.kernel.org
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:34 +01:00
Yan, Zheng
3e05ceedf1 ceph: clear inode pointer when snap realm gets dropped by its inode
commit d95e674c01 upstream.

snap realm and corresponding inode have pointers to each other.
The two pointer should get clear at the same time. Otherwise,
snap realm's pointer may reference freed inode.

Cc: stable@vger.kernel.org # 4.17+
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Luis Henriques <lhenriques@suse.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:34 +01:00
Peter Xu
2011eb7418 userfaultfd: clear flag if remap event not enabled
[ Upstream commit 3cfd22be0a ]

When the process being tracked does mremap() without
UFFD_FEATURE_EVENT_REMAP on the corresponding tracking uffd file handle,
we should not generate the remap event, and at the same time we should
clear all the uffd flags on the new VMA.  Without this patch, we can still
have the VM_UFFD_MISSING|VM_UFFD_WP flags on the new VMA even the fault
handling process does not even know the existance of the VMA.

Link: http://lkml.kernel.org/r/20181211053409.20317-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Hugh Dickins <hughd@google.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Pravin Shedge <pravin.shedge4linux@gmail.com>
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>
2019-01-26 09:32:43 +01:00
Junxiao Bi
5a404f39f8 ocfs2: fix panic due to unrecovered local alloc
[ Upstream commit 532e1e54c8 ]

mount.ocfs2 ignore the inconsistent error that journal is clean but
local alloc is unrecovered.  After mount, local alloc not empty, then
reserver cluster didn't alloc a new local alloc window, reserveration
map is empty(ocfs2_reservation_map.m_bitmap_len = 0), that triggered the
following panic.

This issue was reported at

  https://oss.oracle.com/pipermail/ocfs2-devel/2015-May/010854.html

and was advised to fixed during mount.  But this is a very unusual
inconsistent state, usually journal dirty flag should be cleared at the
last stage of umount until every other things go right.  We may need do
further debug to check that.  Any way to avoid possible futher
corruption, mount should be abort and fsck should be run.

  (mount.ocfs2,1765,1):ocfs2_load_local_alloc:353 ERROR: Local alloc hasn't been recovered!
  found = 6518, set = 6518, taken = 8192, off = 15912372
  ocfs2: Mounting device (202,64) on (node 0, slot 3) with ordered data mode.
  o2dlm: Joining domain 89CEAC63CC4F4D03AC185B44E0EE0F3F ( 0 1 2 3 4 5 6 8 ) 8 nodes
  ocfs2: Mounting device (202,80) on (node 0, slot 3) with ordered data mode.
  o2hb: Region 89CEAC63CC4F4D03AC185B44E0EE0F3F (xvdf) is now a quorum device
  o2net: Accepted connection from node yvwsoa17p (num 7) at 172.22.77.88:7777
  o2dlm: Node 7 joins domain 64FE421C8C984E6D96ED12C55FEE2435 ( 0 1 2 3 4 5 6 7 8 ) 9 nodes
  o2dlm: Node 7 joins domain 89CEAC63CC4F4D03AC185B44E0EE0F3F ( 0 1 2 3 4 5 6 7 8 ) 9 nodes
  ------------[ cut here ]------------
  kernel BUG at fs/ocfs2/reservations.c:507!
  invalid opcode: 0000 [#1] SMP
  Modules linked in: ocfs2 rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs fscache lockd grace ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs sunrpc ipt_REJECT nf_reject_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 ovmapi ppdev parport_pc parport xen_netfront fb_sys_fops sysimgblt sysfillrect syscopyarea acpi_cpufreq pcspkr i2c_piix4 i2c_core sg ext4 jbd2 mbcache2 sr_mod cdrom xen_blkfront pata_acpi ata_generic ata_piix floppy dm_mirror dm_region_hash dm_log dm_mod
  CPU: 0 PID: 4349 Comm: startWebLogic.s Not tainted 4.1.12-124.19.2.el6uek.x86_64 #2
  Hardware name: Xen HVM domU, BIOS 4.4.4OVM 09/06/2018
  task: ffff8803fb04e200 ti: ffff8800ea4d8000 task.ti: ffff8800ea4d8000
  RIP: 0010:[<ffffffffa05e96a8>]  [<ffffffffa05e96a8>] __ocfs2_resv_find_window+0x498/0x760 [ocfs2]
  Call Trace:
    ocfs2_resmap_resv_bits+0x10d/0x400 [ocfs2]
    ocfs2_claim_local_alloc_bits+0xd0/0x640 [ocfs2]
    __ocfs2_claim_clusters+0x178/0x360 [ocfs2]
    ocfs2_claim_clusters+0x1f/0x30 [ocfs2]
    ocfs2_convert_inline_data_to_extents+0x634/0xa60 [ocfs2]
    ocfs2_write_begin_nolock+0x1c6/0x1da0 [ocfs2]
    ocfs2_write_begin+0x13e/0x230 [ocfs2]
    generic_perform_write+0xbf/0x1c0
    __generic_file_write_iter+0x19c/0x1d0
    ocfs2_file_write_iter+0x589/0x1360 [ocfs2]
    __vfs_write+0xb8/0x110
    vfs_write+0xa9/0x1b0
    SyS_write+0x46/0xb0
    system_call_fastpath+0x18/0xd7
  Code: ff ff 8b 75 b8 39 75 b0 8b 45 c8 89 45 98 0f 84 e5 fe ff ff 45 8b 74 24 18 41 8b 54 24 1c e9 56 fc ff ff 85 c0 0f 85 48 ff ff ff <0f> 0b 48 8b 05 cf c3 de ff 48 ba 00 00 00 00 00 00 00 10 48 85
  RIP   __ocfs2_resv_find_window+0x498/0x760 [ocfs2]
   RSP <ffff8800ea4db668>
  ---[ end trace 566f07529f2edf3c ]---
  Kernel panic - not syncing: Fatal exception
  Kernel Offset: disabled

Link: http://lkml.kernel.org/r/20181121020023.3034-2-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Acked-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Changwei Ge <ge.changwei@h3c.com>
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>
2019-01-26 09:32:43 +01:00
Eric Sandeen
c9dcb871b1 iomap: don't search past page end in iomap_is_partially_uptodate
[ Upstream commit 3cc31fa65d ]

iomap_is_partially_uptodate() is intended to check wither blocks within
the selected range of a not-uptodate page are uptodate; if the range we
care about is up to date, it's an optimization.

However, the iomap implementation continues to check all blocks up to
from+count, which is beyond the page, and can even be well beyond the
iop->uptodate bitmap.

I think the worst that will happen is that we may eventually find a zero
bit and return "not partially uptodate" when it would have otherwise
returned true, and skip the optimization.  Still, it's clearly an invalid
memory access that must be fixed.

So: fix this by limiting the search to within the page as is done in the
non-iomap variant, block_is_partially_uptodate().

Zorro noticed thiswhen KASAN went off for 512 byte blocks on a 64k
page system:

 BUG: KASAN: slab-out-of-bounds in iomap_is_partially_uptodate+0x1a0/0x1e0
 Read of size 8 at addr ffff800120c3a318 by task fsstress/22337

Reported-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:43 +01:00
Javier Barrio
876b79b973 quota: Lock s_umount in exclusive mode for Q_XQUOTA{ON,OFF} quotactls.
[ Upstream commit 41c4f85cda ]

Commit 1fa5efe362 (ext4: Use generic helpers for quotaon
and quotaoff) made possible to call quotactl(Q_XQUOTAON/OFF) on ext4 filesystems
with sysfile quota support. This leads to calling dquot_enable/disable without s_umount
held in excl. mode, because quotactl_cmd_onoff checks only for Q_QUOTAON/OFF.

The following WARN_ON_ONCE triggers (in this case for dquot_enable, ext4, latest Linus' tree):

[  117.807056] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: quota,prjquota

[...]

[  155.036847] WARNING: CPU: 0 PID: 2343 at fs/quota/dquot.c:2469 dquot_enable+0x34/0xb9
[  155.036851] Modules linked in: quota_v2 quota_tree ipv6 af_packet joydev mousedev psmouse serio_raw pcspkr i2c_piix4 intel_agp intel_gtt e1000 ttm drm_kms_helper drm agpgart fb_sys_fops syscopyarea sysfillrect sysimgblt i2c_core input_leds kvm_intel kvm irqbypass qemu_fw_cfg floppy evdev parport_pc parport button crc32c_generic dm_mod ata_generic pata_acpi ata_piix libata loop ext4 crc16 mbcache jbd2 usb_storage usbcore sd_mod scsi_mod
[  155.036901] CPU: 0 PID: 2343 Comm: qctl Not tainted 4.20.0-rc6-00025-gf5d582777bcb #9
[  155.036903] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[  155.036911] RIP: 0010:dquot_enable+0x34/0xb9
[  155.036915] Code: 41 56 41 55 41 54 55 53 4c 8b 6f 28 74 02 0f 0b 4d 8d 7d 70 49 89 fc 89 cb 41 89 d6 89 f5 4c 89 ff e8 23 09 ea ff 85 c0 74 0a <0f> 0b 4c 89 ff e8 8b 09 ea ff 85 db 74 6a 41 8b b5 f8 00 00 00 0f
[  155.036918] RSP: 0018:ffffb09b00493e08 EFLAGS: 00010202
[  155.036922] RAX: 0000000000000001 RBX: 0000000000000008 RCX: 0000000000000008
[  155.036924] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9781b67cd870
[  155.036926] RBP: 0000000000000002 R08: 0000000000000000 R09: 61c8864680b583eb
[  155.036929] R10: ffffb09b00493e48 R11: ffffffffff7ce7d4 R12: ffff9781b7ee8d78
[  155.036932] R13: ffff9781b67cd800 R14: 0000000000000004 R15: ffff9781b67cd870
[  155.036936] FS:  00007fd813250b88(0000) GS:ffff9781ba000000(0000) knlGS:0000000000000000
[  155.036939] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  155.036942] CR2: 00007fd812ff61d6 CR3: 000000007c882000 CR4: 00000000000006b0
[  155.036951] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  155.036953] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  155.036955] Call Trace:
[  155.037004]  dquot_quota_enable+0x8b/0xd0
[  155.037011]  kernel_quotactl+0x628/0x74e
[  155.037027]  ? do_mprotect_pkey+0x2a6/0x2cd
[  155.037034]  __x64_sys_quotactl+0x1a/0x1d
[  155.037041]  do_syscall_64+0x55/0xe4
[  155.037078]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  155.037105] RIP: 0033:0x7fd812fe1198
[  155.037109] Code: 02 77 0d 48 89 c1 48 c1 e9 3f 75 04 48 8b 04 24 48 83 c4 50 5b c3 48 83 ec 08 49 89 ca 48 63 d2 48 63 ff b8 b3 00 00 00 0f 05 <48> 89 c7 e8 c1 eb ff ff 5a c3 48 63 ff b8 bb 00 00 00 0f 05 48 89
[  155.037112] RSP: 002b:00007ffe8cd7b050 EFLAGS: 00000206 ORIG_RAX: 00000000000000b3
[  155.037116] RAX: ffffffffffffffda RBX: 00007ffe8cd7b148 RCX: 00007fd812fe1198
[  155.037119] RDX: 0000000000000000 RSI: 00007ffe8cd7cea9 RDI: 0000000000580102
[  155.037121] RBP: 00007ffe8cd7b0f0 R08: 000055fc8eba8a9d R09: 0000000000000000
[  155.037124] R10: 00007ffe8cd7b074 R11: 0000000000000206 R12: 00007ffe8cd7b168
[  155.037126] R13: 000055fc8eba8897 R14: 0000000000000000 R15: 0000000000000000
[  155.037131] ---[ end trace 210f864257175c51 ]---

and then the syscall proceeds without s_umount locking.

This patch locks the superblock ->s_umount sem. in exclusive mode for all Q_XQUOTAON/OFF
quotactls too in addition to Q_QUOTAON/OFF.

AFAICT, other than ext4, only xfs and ocfs2 are affected by this change.
The VFS will now call in xfs_quota_* functions with s_umount held, which wasn't the case
before. This looks good to me but I can not say for sure. Ext4 and ocfs2 where already
beeing called with s_umount exclusive via quota_quotaon/off which is basically the same.

Signed-off-by: Javier Barrio <javier.barrio.mart@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:42 +01:00
Johannes Thumshirn
310f8296d6 btrfs: improve error handling of btrfs_add_link
[ Upstream commit 1690dd41e0 ]

In the error handling block, err holds the return value of either
btrfs_del_root_ref() or btrfs_del_inode_ref() but it hasn't been checked
since it's introduction with commit fe66a05a06 (Btrfs: improve error
handling for btrfs_insert_dir_item callers) in 2012.

If the error handling in the error handling fails, there's not much left
to do and the abort either happened earlier in the callees or is
necessary here.

So if one of btrfs_del_root_ref() or btrfs_del_inode_ref() failed, abort
the transaction, but still return the original code of the failure
stored in 'ret' as this will be reported to the user.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:39 +01:00
Anand Jain
38b17eee70 btrfs: fix use-after-free due to race between replace start and cancel
[ Upstream commit d189dd70e2 ]

The device replace cancel thread can race with the replace start thread
and if fs_info::scrubs_running is not yet set, btrfs_scrub_cancel() will
fail to stop the scrub thread.

The scrub thread continues with the scrub for replace which then will
try to write to the target device and which is already freed by the
cancel thread.

scrub_setup_ctx() warns as tgtdev is NULL.

  struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
  {
  ...
	  if (is_dev_replace) {
		  WARN_ON(!fs_info->dev_replace.tgtdev);  <===
		  sctx->pages_per_wr_bio = SCRUB_PAGES_PER_WR_BIO;
		  sctx->wr_tgtdev = fs_info->dev_replace.tgtdev;
		  sctx->flush_all_writes = false;
	  }

  [ 6724.497655] BTRFS info (device sdb): dev_replace from /dev/sdb (devid 1) to /dev/sdc started
  [ 6753.945017] BTRFS info (device sdb): dev_replace from /dev/sdb (devid 1) to /dev/sdc canceled
  [ 6852.426700] WARNING: CPU: 0 PID: 4494 at fs/btrfs/scrub.c:622 scrub_setup_ctx.isra.19+0x220/0x230 [btrfs]
  ...
  [ 6852.428928] RIP: 0010:scrub_setup_ctx.isra.19+0x220/0x230 [btrfs]
  ...
  [ 6852.432970] Call Trace:
  [ 6852.433202]  btrfs_scrub_dev+0x19b/0x5c0 [btrfs]
  [ 6852.433471]  btrfs_dev_replace_start+0x48c/0x6a0 [btrfs]
  [ 6852.433800]  btrfs_dev_replace_by_ioctl+0x3a/0x60 [btrfs]
  [ 6852.434097]  btrfs_ioctl+0x2476/0x2d20 [btrfs]
  [ 6852.434365]  ? do_sigaction+0x7d/0x1e0
  [ 6852.434623]  do_vfs_ioctl+0xa9/0x6c0
  [ 6852.434865]  ? syscall_trace_enter+0x1c8/0x310
  [ 6852.435124]  ? syscall_trace_enter+0x1c8/0x310
  [ 6852.435387]  ksys_ioctl+0x60/0x90
  [ 6852.435663]  __x64_sys_ioctl+0x16/0x20
  [ 6852.435907]  do_syscall_64+0x50/0x180
  [ 6852.436150]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Further, as the replace thread enters scrub_write_page_to_dev_replace()
without the target device it panics:

  static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
				      struct scrub_page *spage)
  {
  ...
	bio_set_dev(bio, sbio->dev->bdev); <======

  [ 6929.715145] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0
  ..
  [ 6929.717106] Workqueue: btrfs-scrub btrfs_scrub_helper [btrfs]
  [ 6929.717420] RIP: 0010:scrub_write_page_to_dev_replace+0xb4/0x260
  [btrfs]
  ..
  [ 6929.721430] Call Trace:
  [ 6929.721663]  scrub_write_block_to_dev_replace+0x3f/0x60 [btrfs]
  [ 6929.721975]  scrub_bio_end_io_worker+0x1af/0x490 [btrfs]
  [ 6929.722277]  normal_work_helper+0xf0/0x4c0 [btrfs]
  [ 6929.722552]  process_one_work+0x1f4/0x520
  [ 6929.722805]  ? process_one_work+0x16e/0x520
  [ 6929.723063]  worker_thread+0x46/0x3d0
  [ 6929.723313]  kthread+0xf8/0x130
  [ 6929.723544]  ? process_one_work+0x520/0x520
  [ 6929.723800]  ? kthread_delayed_work_timer_fn+0x80/0x80
  [ 6929.724081]  ret_from_fork+0x3a/0x50

Fix this by letting the btrfs_dev_replace_finishing() to do the job of
cleaning after the cancel, including freeing of the target device.
btrfs_dev_replace_finishing() is called when btrfs_scub_dev() returns
along with the scrub return status.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:39 +01:00
Hans van Kranenburg
720b86a53a btrfs: alloc_chunk: fix more DUP stripe size handling
[ Upstream commit baf92114c7 ]

Commit 92e222df7b "btrfs: alloc_chunk: fix DUP stripe size handling"
fixed calculating the stripe_size for a new DUP chunk.

However, the same calculation reappears a bit later, and that one was
not changed yet. The resulting bug that is exposed is that the newly
allocated device extents ('stripes') can have a few MiB overlap with the
next thing stored after them, which is another device extent or the end
of the disk.

The scenario in which this can happen is:
* The block device for the filesystem is less than 10GiB in size.
* The amount of contiguous free unallocated disk space chosen to use for
  chunk allocation is 20% of the total device size, or a few MiB more or
  less.

An example:
- The filesystem device is 7880MiB (max_chunk_size gets set to 788MiB)
- There's 1578MiB unallocated raw disk space left in one contiguous
  piece.

In this case stripe_size is first calculated as 789MiB, (half of
1578MiB).

Since 789MiB (stripe_size * data_stripes) > 788MiB (max_chunk_size), we
enter the if block. Now stripe_size value is immediately overwritten
while calculating an adjusted value based on max_chunk_size, which ends
up as 788MiB.

Next, the value is rounded up to a 16MiB boundary, 800MiB, which is
actually more than the value we had before. However, the last comparison
fails to detect this, because it's comparing the value with the total
amount of free space, which is about twice the size of stripe_size.

In the example above, this means that the resulting raw disk space being
allocated is 1600MiB, while only a gap of 1578MiB has been found. The
second device extent object for this DUP chunk will overlap for 22MiB
with whatever comes next.

The underlying problem here is that the stripe_size is reused all the
time for different things. So, when entering the code in the if block,
stripe_size is immediately overwritten with something else. If later we
decide we want to have the previous value back, then the logic to
compute it was copy pasted in again.

With this change, the value in stripe_size is not unnecessarily
destroyed, so the duplicated calculation is not needed any more.

Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:39 +01:00
Qu Wenruo
bb5717a4a1 btrfs: volumes: Make sure there is no overlap of dev extents at mount time
[ Upstream commit 5eb193812a ]

Enhance btrfs_verify_dev_extents() to remember previous checked dev
extents, so it can verify no dev extents can overlap.

Analysis from Hans:

"Imagine allocating a DATA|DUP chunk.

 In the chunk allocator, we first set...
   max_stripe_size = SZ_1G;
   max_chunk_size = BTRFS_MAX_DATA_CHUNK_SIZE
 ... which is 10GiB.

 Then...
   /* we don't want a chunk larger than 10% of writeable space */
   max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
       		 max_chunk_size);

 Imagine we only have one 7880MiB block device in this filesystem. Now
 max_chunk_size is down to 788MiB.

 The next step in the code is to search for max_stripe_size * dev_stripes
 amount of free space on the device, which is in our example 1GiB * 2 =
 2GiB. Imagine the device has exactly 1578MiB free in one contiguous
 piece. This amount of bytes will be put in devices_info[ndevs - 1].max_avail

 Next we recalculate the stripe_size (which is actually the device extent
 length), based on the actual maximum amount of available raw disk space:
   stripe_size = div_u64(devices_info[ndevs - 1].max_avail, dev_stripes);

 stripe_size is now 789MiB

 Next we do...
   data_stripes = num_stripes / ncopies
 ...where data_stripes ends up as 1, because num_stripes is 2 (the amount
 of device extents we're going to have), and DUP has ncopies 2.

 Next there's a check...
   if (stripe_size * data_stripes > max_chunk_size)
 ...which matches because 789MiB * 1 > 788MiB.

 We go into the if code, and next is...
   stripe_size = div_u64(max_chunk_size, data_stripes);
 ...which resets stripe_size to max_chunk_size: 788MiB

 Next is a fun one...
   /* bump the answer up to a 16MB boundary */
   stripe_size = round_up(stripe_size, SZ_16M);
 ...which changes stripe_size from 788MiB to 800MiB.

 We're not done changing stripe_size yet...
   /* But don't go higher than the limits we found while searching
    * for free extents
    */
   stripe_size = min(devices_info[ndevs - 1].max_avail,
       	      stripe_size);

 This is bad. max_avail is twice the stripe_size (we need to fit 2 device
 extents on the same device for DUP).

 The result here is that 800MiB < 1578MiB, so it's unchanged. However,
 the resulting DUP chunk will need 1600MiB disk space, which isn't there,
 and the second dev_extent might extend into the next thing (next
 dev_extent? end of device?) for 22MiB.

 The last shown line of code relies on a situation where there's twice
 the value of stripe_size present as value for the variable stripe_size
 when it's DUP. This was actually the case before commit 92e222df7b
 "btrfs: alloc_chunk: fix DUP stripe size handling", from which I quote:
   "[...] in the meantime there's a check to see if the stripe_size does
 not exceed max_chunk_size. Since during this check stripe_size is twice
 the amount as intended, the check will reduce the stripe_size to
 max_chunk_size if the actual correct to be used stripe_size is more than
 half the amount of max_chunk_size."

 In the previous version of the code, the 16MiB alignment (why is this
 done, by the way?) would result in a 50% chance that it would actually
 do an 8MiB alignment for the individual dev_extents, since it was
 operating on double the size. Does this matter?

 Does it matter that stripe_size can be set to anything which is not
 16MiB aligned because of the amount of remaining available disk space
 which is just taken?

 What is the main purpose of this round_up?

 The most straightforward thing to do seems something like...
   stripe_size = min(
       div_u64(devices_info[ndevs - 1].max_avail, dev_stripes),
       stripe_size
   )
 ..just putting half of the max_avail into stripe_size."

Link: https://lore.kernel.org/linux-btrfs/b3461a38-e5f8-f41d-c67c-2efac8129054@mendix.com/
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ add analysis from report ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:39 +01:00
Joel Fernandes (Google)
265242d82a pstore/ram: Do not treat empty buffers as valid
[ Upstream commit 30696378f6 ]

The ramoops backend currently calls persistent_ram_save_old() even
if a buffer is empty. While this appears to work, it is does not seem
like the right thing to do and could lead to future bugs so lets avoid
that. It also prevents misleading prints in the logs which claim the
buffer is valid.

I got something like:

	found existing buffer, size 0, start 0

When I was expecting:

	no valid data in buffer (sig = ...)

This bails out early (and reports with pr_debug()), since it's an
acceptable state.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:37 +01:00
Daniel Santos
c356972f27 jffs2: Fix use of uninitialized delayed_work, lockdep breakage
[ Upstream commit a788c52727 ]

jffs2_sync_fs makes the assumption that if CONFIG_JFFS2_FS_WRITEBUFFER
is defined then a write buffer is available and has been initialized.
However, this does is not the case when the mtd device has no
out-of-band buffer:

int jffs2_nand_flash_setup(struct jffs2_sb_info *c)
{
        if (!c->mtd->oobsize)
                return 0;
...

The resulting call to cancel_delayed_work_sync passing a uninitialized
(but zeroed) delayed_work struct forces lockdep to become disabled.

[   90.050639] overlayfs: upper fs does not support tmpfile.
[   90.652264] INFO: trying to register non-static key.
[   90.662171] the code is fine but needs lockdep annotation.
[   90.673090] turning off the locking correctness validator.
[   90.684021] CPU: 0 PID: 1762 Comm: mount_root Not tainted 4.14.63 #0
[   90.696672] Stack : 00000000 00000000 80d8f6a2 00000038 805f0000 80444600 8fe364f4 805dfbe7
[   90.713349]         80563a30 000006e2 8068370c 00000001 00000000 00000001 8e2fdc48 ffffffff
[   90.730020]         00000000 00000000 80d90000 00000000 00000106 00000000 6465746e 312e3420
[   90.746690]         6b636f6c 03bf0000 f8000000 20676e69 00000000 80000000 00000000 8e2c2a90
[   90.763362]         80d90000 00000001 00000000 8e2c2a90 00000003 80260dc0 08052098 80680000
[   90.780033]         ...
[   90.784902] Call Trace:
[   90.789793] [<8000f0d8>] show_stack+0xb8/0x148
[   90.798659] [<8005a000>] register_lock_class+0x270/0x55c
[   90.809247] [<8005cb64>] __lock_acquire+0x13c/0xf7c
[   90.818964] [<8005e314>] lock_acquire+0x194/0x1dc
[   90.828345] [<8003f27c>] flush_work+0x200/0x24c
[   90.837374] [<80041dfc>] __cancel_work_timer+0x158/0x210
[   90.847958] [<801a8770>] jffs2_sync_fs+0x20/0x54
[   90.857173] [<80125cf4>] iterate_supers+0xf4/0x120
[   90.866729] [<80158fc4>] sys_sync+0x44/0x9c
[   90.875067] [<80014424>] syscall_common+0x34/0x58

Signed-off-by: Daniel Santos <daniel.santos@pobox.com>
Reviewed-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:37 +01:00
Jan Kara
1e11b1d630 blockdev: Fix livelocks on loop device
commit 04906b2f54 upstream.

bd_set_size() updates also block device's block size. This is somewhat
unexpected from its name and at this point, only blkdev_open() uses this
functionality. Furthermore, this can result in changing block size under
a filesystem mounted on a loop device which leads to livelocks inside
__getblk_gfp() like:

Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10863 Comm: syz-executor0 Not tainted 4.18.0-rc5+ #151
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google
01/01/2011
RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x50 kernel/kcov.c:106
...
Call Trace:
 init_page_buffers+0x3e2/0x530 fs/buffer.c:904
 grow_dev_page fs/buffer.c:947 [inline]
 grow_buffers fs/buffer.c:1009 [inline]
 __getblk_slow fs/buffer.c:1036 [inline]
 __getblk_gfp+0x906/0xb10 fs/buffer.c:1313
 __bread_gfp+0x2d/0x310 fs/buffer.c:1347
 sb_bread include/linux/buffer_head.h:307 [inline]
 fat12_ent_bread+0x14e/0x3d0 fs/fat/fatent.c:75
 fat_ent_read_block fs/fat/fatent.c:441 [inline]
 fat_alloc_clusters+0x8ce/0x16e0 fs/fat/fatent.c:489
 fat_add_cluster+0x7a/0x150 fs/fat/inode.c:101
 __fat_get_block fs/fat/inode.c:148 [inline]
...

Trivial reproducer for the problem looks like:

truncate -s 1G /tmp/image
losetup /dev/loop0 /tmp/image
mkfs.ext4 -b 1024 /dev/loop0
mount -t ext4 /dev/loop0 /mnt
losetup -c /dev/loop0
l /mnt

Fix the problem by moving initialization of a block device block size
into a separate function and call it when needed.

Thanks to Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> for help with
debugging the problem.

Reported-by: syzbot+9933e4476f365f5d5a1b@syzkaller.appspotmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22 21:40:36 +01:00
Kees Cook
483ac8e65a pstore/ram: Avoid allocation and leak of platform data
commit 5631e8576a upstream.

Yue Hu noticed that when parsing device tree the allocated platform data
was never freed. Since it's not used beyond the function scope, this
switches to using a stack variable instead.

Reported-by: Yue Hu <huyue2@yulong.com>
Fixes: 35da60941e ("pstore/ram: add Device Tree bindings")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22 21:40:34 +01:00
Josef Bacik
01634ac563 btrfs: wait on ordered extents on abort cleanup
commit 74d5d229b1 upstream.

If we flip read-only before we initiate writeback on all dirty pages for
ordered extents we've created then we'll have ordered extents left over
on umount, which results in all sorts of bad things happening.  Fix this
by making sure we wait on ordered extents if we have to do the aborted
transaction cleanup stuff.

generic/475 can produce this warning:

 [ 8531.177332] WARNING: CPU: 2 PID: 11997 at fs/btrfs/disk-io.c:3856 btrfs_free_fs_root+0x95/0xa0 [btrfs]
 [ 8531.183282] CPU: 2 PID: 11997 Comm: umount Tainted: G        W 5.0.0-rc1-default+ #394
 [ 8531.185164] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),BIOS rel-1.11.2-0-gf9626cc-prebuilt.qemu-project.org 04/01/2014
 [ 8531.187851] RIP: 0010:btrfs_free_fs_root+0x95/0xa0 [btrfs]
 [ 8531.193082] RSP: 0018:ffffb1ab86163d98 EFLAGS: 00010286
 [ 8531.194198] RAX: ffff9f3449494d18 RBX: ffff9f34a2695000 RCX:0000000000000000
 [ 8531.195629] RDX: 0000000000000002 RSI: 0000000000000001 RDI:0000000000000000
 [ 8531.197315] RBP: ffff9f344e930000 R08: 0000000000000001 R09:0000000000000000
 [ 8531.199095] R10: 0000000000000000 R11: ffff9f34494d4ff8 R12:ffffb1ab86163dc0
 [ 8531.200870] R13: ffff9f344e9300b0 R14: ffffb1ab86163db8 R15:0000000000000000
 [ 8531.202707] FS:  00007fc68e949fc0(0000) GS:ffff9f34bd800000(0000)knlGS:0000000000000000
 [ 8531.204851] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [ 8531.205942] CR2: 00007ffde8114dd8 CR3: 000000002dfbd000 CR4:00000000000006e0
 [ 8531.207516] Call Trace:
 [ 8531.208175]  btrfs_free_fs_roots+0xdb/0x170 [btrfs]
 [ 8531.210209]  ? wait_for_completion+0x5b/0x190
 [ 8531.211303]  close_ctree+0x157/0x350 [btrfs]
 [ 8531.212412]  generic_shutdown_super+0x64/0x100
 [ 8531.213485]  kill_anon_super+0x14/0x30
 [ 8531.214430]  btrfs_kill_super+0x12/0xa0 [btrfs]
 [ 8531.215539]  deactivate_locked_super+0x29/0x60
 [ 8531.216633]  cleanup_mnt+0x3b/0x70
 [ 8531.217497]  task_work_run+0x98/0xc0
 [ 8531.218397]  exit_to_usermode_loop+0x83/0x90
 [ 8531.219324]  do_syscall_64+0x15b/0x180
 [ 8531.220192]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 [ 8531.221286] RIP: 0033:0x7fc68e5e4d07
 [ 8531.225621] RSP: 002b:00007ffde8116608 EFLAGS: 00000246 ORIG_RAX:00000000000000a6
 [ 8531.227512] RAX: 0000000000000000 RBX: 00005580c2175970 RCX:00007fc68e5e4d07
 [ 8531.229098] RDX: 0000000000000001 RSI: 0000000000000000 RDI:00005580c2175b80
 [ 8531.230730] RBP: 0000000000000000 R08: 00005580c2175ba0 R09:00007ffde8114e80
 [ 8531.232269] R10: 0000000000000000 R11: 0000000000000246 R12:00005580c2175b80
 [ 8531.233839] R13: 00007fc68eac61c4 R14: 00005580c2175a68 R15:0000000000000000

Leaving a tree in the rb-tree:

3853 void btrfs_free_fs_root(struct btrfs_root *root)
3854 {
3855         iput(root->ino_cache_inode);
3856         WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));

CC: stable@vger.kernel.org
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
[ add stacktrace ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22 21:40:32 +01:00
David Sterba
4675f90ef8 Revert "btrfs: balance dirty metadata pages in btrfs_finish_ordered_io"
commit 77b7aad195 upstream.

This reverts commit e73e81b6d0.

This patch causes a few problems:

- adds latency to btrfs_finish_ordered_io
- as btrfs_finish_ordered_io is used for free space cache, generating
  more work from btrfs_btree_balance_dirty_nodelay could end up in the
  same workque, effectively deadlocking

12260 kworker/u96:16+btrfs-freespace-write D
[<0>] balance_dirty_pages+0x6e6/0x7ad
[<0>] balance_dirty_pages_ratelimited+0x6bb/0xa90
[<0>] btrfs_finish_ordered_io+0x3da/0x770
[<0>] normal_work_helper+0x1c5/0x5a0
[<0>] process_one_work+0x1ee/0x5a0
[<0>] worker_thread+0x46/0x3d0
[<0>] kthread+0xf5/0x130
[<0>] ret_from_fork+0x24/0x30
[<0>] 0xffffffffffffffff

Transaction commit will wait on the freespace cache:

838 btrfs-transacti D
[<0>] btrfs_start_ordered_extent+0x154/0x1e0
[<0>] btrfs_wait_ordered_range+0xbd/0x110
[<0>] __btrfs_wait_cache_io+0x49/0x1a0
[<0>] btrfs_write_dirty_block_groups+0x10b/0x3b0
[<0>] commit_cowonly_roots+0x215/0x2b0
[<0>] btrfs_commit_transaction+0x37e/0x910
[<0>] transaction_kthread+0x14d/0x180
[<0>] kthread+0xf5/0x130
[<0>] ret_from_fork+0x24/0x30
[<0>] 0xffffffffffffffff

And then writepages ends up waiting on transaction commit:

9520 kworker/u96:13+flush-btrfs-1 D
[<0>] wait_current_trans+0xac/0xe0
[<0>] start_transaction+0x21b/0x4b0
[<0>] cow_file_range_inline+0x10b/0x6b0
[<0>] cow_file_range.isra.69+0x329/0x4a0
[<0>] run_delalloc_range+0x105/0x3c0
[<0>] writepage_delalloc+0x119/0x180
[<0>] __extent_writepage+0x10c/0x390
[<0>] extent_write_cache_pages+0x26f/0x3d0
[<0>] extent_writepages+0x4f/0x80
[<0>] do_writepages+0x17/0x60
[<0>] __writeback_single_inode+0x59/0x690
[<0>] writeback_sb_inodes+0x291/0x4e0
[<0>] __writeback_inodes_wb+0x87/0xb0
[<0>] wb_writeback+0x3bb/0x500
[<0>] wb_workfn+0x40d/0x610
[<0>] process_one_work+0x1ee/0x5a0
[<0>] worker_thread+0x1e0/0x3d0
[<0>] kthread+0xf5/0x130
[<0>] ret_from_fork+0x24/0x30
[<0>] 0xffffffffffffffff

Eventually, we have every process in the system waiting on
balance_dirty_pages(), and nobody is able to make progress on page
writeback.

The original patch tried to fix an OOM condition, that happened on 4.4 but no
success reproducing that on later kernels (4.19 and 4.20). This is more likely
a problem in OOM itself.

Link: https://lore.kernel.org/linux-btrfs/20180528054821.9092-1-ethanlien@synology.com/
Reported-by: Chris Mason <clm@fb.com>
CC: stable@vger.kernel.org # 4.18+
CC: ethanlien <ethanlien@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22 21:40:32 +01:00
Filipe Manana
7a1b9b76ba Btrfs: use nofs context when initializing security xattrs to avoid deadlock
commit 827aa18e7b upstream.

When initializing the security xattrs, we are holding a transaction handle
therefore we need to use a GFP_NOFS context in order to avoid a deadlock
with reclaim in case it's triggered.

Fixes: 39a27ec100 ("btrfs: use GFP_KERNEL for xattr and acl allocations")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:04:37 +01:00
Filipe Manana
79aa5c0daa Btrfs: fix deadlock when enabling quotas due to concurrent snapshot creation
commit 9a6f209e36 upstream.

If the quota enable and snapshot creation ioctls are called concurrently
we can get into a deadlock where the task enabling quotas will deadlock
on the fs_info->qgroup_ioctl_lock mutex because it attempts to lock it
twice, or the task creating a snapshot tries to commit the transaction
while the task enabling quota waits for the former task to commit the
transaction while holding the mutex. The following time diagrams show how
both cases happen.

First scenario:

           CPU 0                                    CPU 1

 btrfs_ioctl()
  btrfs_ioctl_quota_ctl()
   btrfs_quota_enable()
    mutex_lock(fs_info->qgroup_ioctl_lock)
    btrfs_start_transaction()

                                             btrfs_ioctl()
                                              btrfs_ioctl_snap_create_v2
                                               create_snapshot()
                                                --> adds snapshot to the
                                                    list pending_snapshots
                                                    of the current
                                                    transaction

    btrfs_commit_transaction()
     create_pending_snapshots()
       create_pending_snapshot()
        qgroup_account_snapshot()
         btrfs_qgroup_inherit()
	   mutex_lock(fs_info->qgroup_ioctl_lock)
	    --> deadlock, mutex already locked
	        by this task at
		btrfs_quota_enable()

Second scenario:

           CPU 0                                    CPU 1

 btrfs_ioctl()
  btrfs_ioctl_quota_ctl()
   btrfs_quota_enable()
    mutex_lock(fs_info->qgroup_ioctl_lock)
    btrfs_start_transaction()

                                             btrfs_ioctl()
                                              btrfs_ioctl_snap_create_v2
                                               create_snapshot()
                                                --> adds snapshot to the
                                                    list pending_snapshots
                                                    of the current
                                                    transaction

                                                btrfs_commit_transaction()
                                                 --> waits for task at
                                                     CPU 0 to release
                                                     its transaction
                                                     handle

    btrfs_commit_transaction()
     --> sees another task started
         the transaction commit first
     --> releases its transaction
         handle
     --> waits for the transaction
         commit to be completed by
         the task at CPU 1

                                                 create_pending_snapshot()
                                                  qgroup_account_snapshot()
                                                   btrfs_qgroup_inherit()
                                                    mutex_lock(fs_info->qgroup_ioctl_lock)
                                                     --> deadlock, task at CPU 0
                                                         has the mutex locked but
                                                         it is waiting for us to
                                                         finish the transaction
                                                         commit

So fix this by setting the quota enabled flag in fs_info after committing
the transaction at btrfs_quota_enable(). This ends up serializing quota
enable and snapshot creation as if the snapshot creation happened just
before the quota enable request. The quota rescan task, scheduled after
committing the transaction in btrfs_quote_enable(), will do the accounting.

Fixes: 6426c7ad69 ("btrfs: qgroup: Fix qgroup accounting when creating snapshot")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:04:37 +01:00
Filipe Manana
829431a2a5 Btrfs: fix access to available allocation bits when starting balance
commit 5a8067c0d1 upstream.

The available allocation bits members from struct btrfs_fs_info are
protected by a sequence lock, and when starting balance we access them
incorrectly in two different ways:

1) In the read sequence lock loop at btrfs_balance() we use the values we
   read from fs_info->avail_*_alloc_bits and we can immediately do actions
   that have side effects and can not be undone (printing a message and
   jumping to a label). This is wrong because a retry might be needed, so
   our actions must not have side effects and must be repeatable as long
   as read_seqretry() returns a non-zero value. In other words, we were
   essentially ignoring the sequence lock;

2) Right below the read sequence lock loop, we were reading the values
   from avail_metadata_alloc_bits and avail_data_alloc_bits without any
   protection from concurrent writers, that is, reading them outside of
   the read sequence lock critical section.

So fix this by making sure we only read the available allocation bits
while in a read sequence lock critical section and that what we do in the
critical section is repeatable (has nothing that can not be undone) so
that any eventual retry that is needed is handled properly.

Fixes: de98ced9e7 ("Btrfs: use seqlock to protect fs_info->avail_{data, metadata, system}_alloc_bits")
Fixes: 1450612797 ("btrfs: fix a bogus warning when converting only data or metadata")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:04:37 +01:00
Theodore Ts'o
5dc41af3d1 ext4: fix special inode number checks in __ext4_iget()
commit 191ce17876 upstream.

The check for special (reserved) inode number checks in __ext4_iget()
was broken by commit 8a363970d1dc: ("ext4: avoid declaring fs
inconsistent due to invalid file handles").  This was caused by a
botched reversal of the sense of the flag now known as
EXT4_IGET_SPECIAL (when it was previously named EXT4_IGET_NORMAL).
Fix the logic appropriately.

Fixes: 8a363970d1 ("ext4: avoid declaring fs inconsistent...")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:04:36 +01:00