Commit Graph

64045 Commits

Author SHA1 Message Date
David Howells
c4bfda16d1 afs: Make record checking use TASK_UNINTERRUPTIBLE when appropriate
When an operation is meant to be done uninterruptibly (such as
FS.StoreData), we should not be allowing volume and server record checking
to be interrupted.

Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-24 16:33:32 +01:00
David Howells
69cf3978f3 afs: Fix to actually set AFS_SERVER_FL_HAVE_EPOCH
AFS keeps track of the epoch value from the rxrpc protocol to note (a) when
a fileserver appears to have restarted and (b) when different endpoints of
a fileserver do not appear to be associated with the same fileserver
(ie. all probes back from a fileserver from all of its interfaces should
carry the same epoch).

However, the AFS_SERVER_FL_HAVE_EPOCH flag that indicates that we've
received the server's epoch is never set, though it is used.

Fix this to set the flag when we first receive an epoch value from a probe
sent to the filesystem client from the fileserver.

Fixes: 3bf0fb6f33 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-24 16:32:49 +01:00
David Howells
be59167c8f afs: Remove some unused bits
Remove three bits:

 (1) afs_server::no_epoch is neither set nor used.

 (2) afs_server::have_result is set and a wakeup is applied to it, but
     nothing looks at it or waits on it.

 (3) afs_vl_dump_edestaddrreq() prints afs_addr_list::probed, but nothing
     sets it for VL servers.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-24 16:32:49 +01:00
Al Viro
3815f1be54 dlmfs_file_write(): fix the bogosity in handling non-zero *ppos
'count' is how much you want written, not the final position.
Moreover, it can legitimately be less than the current position...

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-23 13:45:27 -04:00
Linus Torvalds
1ddd873948 Fixes:
- Address several use-after-free and memory leak bugs
 
 - Prevent a backchannel livelock
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Merge tag 'nfsd-5.7-rc-1' of git://git.linux-nfs.org/projects/cel/cel-2.6

Pull nfsd fixes from Chuck Lever:
 "The first set of 5.7-rc fixes for NFS server issues.

  These were all unresolved at the time the 5.7 window opened, and
  needed some additional time to ensure they were correctly addressed.
  They are ready now.

  At the moment I know of one more urgent issue regarding the NFS
  server. A fix has been tested and is under review. I expect to send
  one more pull request, containing this fix (which now consists of 3
  patches).

  Fixes:

   - Address several use-after-free and memory leak bugs

   - Prevent a backchannel livelock"

* tag 'nfsd-5.7-rc-1' of git://git.linux-nfs.org/projects/cel/cel-2.6:
  svcrdma: Fix leak of svc_rdma_recv_ctxt objects
  svcrdma: Fix trace point use-after-free race
  SUNRPC: Fix backchannel RPC soft lockups
  SUNRPC/cache: Fix unsafe traverse caused double-free in cache_purge
  nfsd: memory corruption in nfsd4_lock()
2020-04-23 09:33:43 -07:00
Linus Torvalds
6f8cd037a5 Description for this pull request:
- several bug fixes(broken mount discard option, remount failure, memory leak)
 - add missing MODULE_ALIAS_FS for automatically loading exfat module.
 - set s_time_gran and truncate atime with exfat timestamp granularity.
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Merge tag 'for-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat

Pull exfat fixes from Namjae Jeon:

 - several bug fixes(broken mount discard option, remount failure,
   memory leak)

 - add missing MODULE_ALIAS_FS for automatically loading exfat module.

 - set s_time_gran and truncate atime with exfat timestamp granularity.

* tag 'for-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
  exfat: truncate atimes to 2s granularity
  exfat: properly set s_time_gran
  exfat: remove 'bps' mount-option
  exfat: Unify access to the boot sector
  exfat: add missing MODULE_ALIAS_FS()
  exfat: Fix discard support
2020-04-23 09:31:20 -07:00
Xiyu Yang
1402d17dfd btrfs: fix transaction leak in btrfs_recover_relocation
btrfs_recover_relocation() invokes btrfs_join_transaction(), which joins
a btrfs_trans_handle object into transactions and returns a reference of
it with increased refcount to "trans".

When btrfs_recover_relocation() returns, "trans" becomes invalid, so the
refcount should be decreased to keep refcount balanced.

The reference counting issue happens in one exception handling path of
btrfs_recover_relocation(). When read_fs_root() failed, the refcnt
increased by btrfs_join_transaction() is not decreased, causing a refcnt
leak.

Fix this issue by calling btrfs_end_transaction() on this error path
when read_fs_root() failed.

Fixes: 79787eaab4 ("btrfs: replace many BUG_ONs with proper error handling")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-23 17:24:56 +02:00
Xiyu Yang
f6033c5e33 btrfs: fix block group leak when removing fails
btrfs_remove_block_group() invokes btrfs_lookup_block_group(), which
returns a local reference of the block group that contains the given
bytenr to "block_group" with increased refcount.

When btrfs_remove_block_group() returns, "block_group" becomes invalid,
so the refcount should be decreased to keep refcount balanced.

The reference counting issue happens in several exception handling paths
of btrfs_remove_block_group(). When those error scenarios occur such as
btrfs_alloc_path() returns NULL, the function forgets to decrease its
refcnt increased by btrfs_lookup_block_group() and will cause a refcnt
leak.

Fix this issue by jumping to "out_put_group" label and calling
btrfs_put_block_group() when those error scenarios occur.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-23 17:24:52 +02:00
Josef Bacik
ef67963dac btrfs: drop logs when we've aborted a transaction
Dave reported a problem where we were panicing with generic/475 with
misc-5.7.  This is because we were doing IO after we had stopped all of
the worker threads, because we do the log tree cleanup on roots at drop
time.  Cleaning up the log tree will always need to do reads if we
happened to have evicted the blocks from memory.

Because of this simply add a helper to btrfs_cleanup_transaction() that
will go through and drop all of the log roots.  This gets run before we
do the close_ctree() work, and thus we are allowed to do any reads that
we would need.  I ran this through many iterations of generic/475 with
constrained memory and I did not see the issue.

  general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
  CPU: 2 PID: 12359 Comm: umount Tainted: G        W 5.6.0-rc7-btrfs-next-58 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
  RIP: 0010:btrfs_queue_work+0x33/0x1c0 [btrfs]
  RSP: 0018:ffff9cfb015937d8 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffff8eb5e339ed80 RCX: 0000000000000000
  RDX: 0000000000000001 RSI: ffff8eb5eb33b770 RDI: ffff8eb5e37a0460
  RBP: ffff8eb5eb33b770 R08: 000000000000020c R09: ffffffff9fc09ac0
  R10: 0000000000000007 R11: 0000000000000000 R12: 6b6b6b6b6b6b6b6b
  R13: ffff9cfb00229040 R14: 0000000000000008 R15: ffff8eb5d3868000
  FS:  00007f167ea022c0(0000) GS:ffff8eb5fae00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f167e5e0cb1 CR3: 0000000138c18004 CR4: 00000000003606e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   btrfs_end_bio+0x81/0x130 [btrfs]
   __split_and_process_bio+0xaf/0x4e0 [dm_mod]
   ? percpu_counter_add_batch+0xa3/0x120
   dm_process_bio+0x98/0x290 [dm_mod]
   ? generic_make_request+0xfb/0x410
   dm_make_request+0x4d/0x120 [dm_mod]
   ? generic_make_request+0xfb/0x410
   generic_make_request+0x12a/0x410
   ? submit_bio+0x38/0x160
   submit_bio+0x38/0x160
   ? percpu_counter_add_batch+0xa3/0x120
   btrfs_map_bio+0x289/0x570 [btrfs]
   ? kmem_cache_alloc+0x24d/0x300
   btree_submit_bio_hook+0x79/0xc0 [btrfs]
   submit_one_bio+0x31/0x50 [btrfs]
   read_extent_buffer_pages+0x2fe/0x450 [btrfs]
   btree_read_extent_buffer_pages+0x7e/0x170 [btrfs]
   walk_down_log_tree+0x343/0x690 [btrfs]
   ? walk_log_tree+0x3d/0x380 [btrfs]
   walk_log_tree+0xf7/0x380 [btrfs]
   ? plist_requeue+0xf0/0xf0
   ? delete_node+0x4b/0x230
   free_log_tree+0x4c/0x130 [btrfs]
   ? wait_log_commit+0x140/0x140 [btrfs]
   btrfs_free_log+0x17/0x30 [btrfs]
   btrfs_drop_and_free_fs_root+0xb0/0xd0 [btrfs]
   btrfs_free_fs_roots+0x10c/0x190 [btrfs]
   ? do_raw_spin_unlock+0x49/0xc0
   ? _raw_spin_unlock+0x29/0x40
   ? release_extent_buffer+0x121/0x170 [btrfs]
   close_ctree+0x289/0x2e6 [btrfs]
   generic_shutdown_super+0x6c/0x110
   kill_anon_super+0xe/0x30
   btrfs_kill_super+0x12/0x20 [btrfs]
   deactivate_locked_super+0x3a/0x70

Reported-by: David Sterba <dsterba@suse.com>
Fixes: 8c38938c7b ("btrfs: move the root freeing stuff into btrfs_put_root")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-23 17:23:11 +02:00
Filipe Manana
5150bf1963 btrfs: fix memory leak of transaction when deleting unused block group
When cleaning pinned extents right before deleting an unused block group,
we check if there's still a previous transaction running and if so we
increment its reference count before using it for cleaning pinned ranges
in its pinned extents iotree. However we ended up never decrementing the
reference count after using the transaction, resulting in a memory leak.

Fix it by decrementing the reference count.

Fixes: fe119a6eeb ("btrfs: switch to per-transaction pinned extents")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-23 17:22:45 +02:00
Paulo Alcantara
0fe0781f29 cifs: fix uninitialised lease_key in open_shroot()
SMB2_open_init() expects a pre-initialised lease_key when opening a
file with a lease, so set pfid->lease_key prior to calling it in
open_shroot().

This issue was observed when performing some DFS failover tests and
the lease key was never randomly generated.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
2020-04-22 20:29:11 -05:00
Paulo Alcantara
3786f4bddc cifs: ensure correct super block for DFS reconnect
This patch is basically fixing the lookup of tcons (DFS specific) during
reconnect (smb2pdu.c:__smb2_reconnect) to update their prefix paths.

Previously, we relied on the TCP_Server_Info pointer
(misc.c:tcp_super_cb) to determine which tcon to update the prefix path

We could not rely on TCP server pointer to determine which super block
to update the prefix path when reconnecting tcons since it might map
to different tcons that share same TCP connection.

Instead, walk through all cifs super blocks and compare their DFS full
paths with the tcon being updated to.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-04-22 20:27:30 -05:00
Paulo Alcantara
65303de829 cifs: do not share tcons with DFS
This disables tcon re-use for DFS shares.

tcon->dfs_path stores the path that the tcon should connect to when
doing failing over.

If that tcon is used multiple times e.g. 2 mounts using it with
different prefixpath, each will need a different dfs_path but there is
only one tcon. The other solution would be to split the tcon in 2
tcons during failover but that is much harder.

tcons could not be shared with DFS in cifs.ko because in a
DFS namespace like:

          //domain/dfsroot -> /serverA/dfsroot, /serverB/dfsroot

          //serverA/dfsroot/link -> /serverA/target1/aa/bb

          //serverA/dfsroot/link2 -> /serverA/target1/cc/dd

you can see that link and link2 are two DFS links that both resolve to
the same target share (/serverA/target1), so cifs.ko will only contain a
single tcon for both link and link2.

The problem with that is, if we (auto)mount "link" and "link2", cifs.ko
will only contain a single tcon for both DFS links so we couldn't
perform failover or refresh the DFS cache for both links because
tcon->dfs_path was set to either "link" or "link2", but not both --
which is wrong.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-22 20:22:08 -05:00
Eric Sandeen
81df1ad406 exfat: truncate atimes to 2s granularity
The timestamp for access_time has double seconds granularity(There is no
10msIncrement field for access_time unlike create/modify_time).
exfat's atimes are restricted to only 2s granularity so after
we set an atime, round it down to the nearest 2s and set the
sub-second component of the timestamp to 0.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
2020-04-22 20:14:06 +09:00
Eric Sandeen
674a9985b8 exfat: properly set s_time_gran
The s_time_gran superblock field indicates the on-disk nanosecond
granularity of timestamps, and for exfat that seems to be 10ms, so
set s_time_gran to 10000000ns. Without this, in-memory timestamps
change when they get re-read from disk.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
2020-04-22 20:14:06 +09:00
Tetsuhiro Kohada
cbd445d9a9 exfat: remove 'bps' mount-option
remount fails because exfat_show_options() returns unsupported
option 'bps'.
> # mount -o ro,remount
> exfat: Unknown parameter 'bps'

To fix the problem, just remove 'bps' option from exfat_show_options().

Signed-off-by: Tetsuhiro Kohada <Kohada.Tetsuhiro@dc.MitsubishiElectric.co.jp>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
2020-04-22 20:14:05 +09:00
Tetsuhiro Kohada
b0516833d8 exfat: Unify access to the boot sector
Unify access to boot sector via 'sbi->pbr_bh'.
This fixes vol_flags inconsistency at read failed in fs_set_vol_flags(),
and buffer_head leak in __exfat_fill_super().

Signed-off-by: Tetsuhiro Kohada <Kohada.Tetsuhiro@dc.MitsubishiElectric.co.jp>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
2020-04-22 20:14:05 +09:00
Thomas Backlund
cd76ac258c exfat: add missing MODULE_ALIAS_FS()
This adds the necessary MODULE_ALIAS_FS() to exfat so the module gets
automatically loaded when an exfat filesystem is mounted.

Signed-off-by: Thomas Backlund <tmb@mageia.org>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
2020-04-22 20:14:05 +09:00
Pali Rohár
b7e038a924 exfat: Fix discard support
Discard support was always unconditionally disabled. Now it is disabled
only in the case when blk_queue_discard() returns false.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
2020-04-22 20:14:05 +09:00
Steve French
d92c7ce41e cifs: minor update to comments around the cifs_tcp_ses_lock mutex
Update comment to note that it protects server->dstaddr

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-21 23:51:18 -05:00
Sudip Mukherjee
db973a7289 coredump: fix null pointer dereference on coredump
If the core_pattern is set to "|" and any process segfaults then we get
a null pointer derefernce while trying to coredump. The call stack shows:

    RIP: do_coredump+0x628/0x11c0

When the core_pattern has only "|" there is no use of trying the
coredump and we can check that while formating the corename and exit
with an error.

After this change I get:

    format_corename failed
    Aborting core

Fixes: 315c69261d ("coredump: split pipe command whitespace before expanding template")
Reported-by: Matthew Ruffell <matthew.ruffell@canonical.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Wise <pabs3@bonedaddy.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416194612.21418-1-sudipm.mukherjee@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-21 11:11:56 -07:00
Jann Horn
bdebd6a283 vmalloc: fix remap_vmalloc_range() bounds checks
remap_vmalloc_range() has had various issues with the bounds checks it
promises to perform ("This function checks that addr is a valid
vmalloc'ed area, and that it is big enough to cover the vma") over time,
e.g.:

 - not detecting pgoff<<PAGE_SHIFT overflow

 - not detecting (pgoff<<PAGE_SHIFT)+usize overflow

 - not checking whether addr and addr+(pgoff<<PAGE_SHIFT) are the same
   vmalloc allocation

 - comparing a potentially wildly out-of-bounds pointer with the end of
   the vmalloc region

In particular, since commit fc9702273e ("bpf: Add mmap() support for
BPF_MAP_TYPE_ARRAY"), unprivileged users can cause kernel null pointer
dereferences by calling mmap() on a BPF map with a size that is bigger
than the distance from the start of the BPF map to the end of the
address space.

This could theoretically be used as a kernel ASLR bypass, by using
whether mmap() with a given offset oopses or returns an error code to
perform a binary search over the possible address range.

To allow remap_vmalloc_range_partial() to verify that addr and
addr+(pgoff<<PAGE_SHIFT) are in the same vmalloc region, pass the offset
to remap_vmalloc_range_partial() instead of adding it to the pointer in
remap_vmalloc_range().

In remap_vmalloc_range_partial(), fix the check against
get_vm_area_size() by using size comparisons instead of pointer
comparisons, and add checks for pgoff.

Fixes: 833423143c ("[PATCH] mm: introduce remap_vmalloc_range()")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Link: http://lkml.kernel.org/r/20200415222312.236431-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-21 11:11:56 -07:00
Ma, Jianpeng
d56deb1e4e block: remove unused header
Dax related code already removed from this file.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jianpeng Ma <jianpeng.ma@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-21 09:51:10 -06:00
Ronnie Sahlberg
fada37f6f6 cifs: protect updating server->dstaddr with a spinlock
We use a spinlock while we are reading and accessing the destination address for a server.
We need to also use this spinlock to protect when we are modifying this address from
reconn_set_ipaddr().

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-21 09:57:56 -05:00
Nishad Kamdar
317ddf3715 btrfs: discard: Use the correct style for SPDX License Identifier
This patch corrects the SPDX License Identifier style in header file
related to Btrfs File System support.  For C header files
Documentation/process/license-rules.rst mandates C-like comments
(opposed to C source files where C++ style should be used).

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-20 17:43:42 +02:00
Douglas Anderson
b849dd84b6 bdev: Reduce time holding bd_mutex in sync in blkdev_close()
While trying to "dd" to the block device for a USB stick, I
encountered a hung task warning (blocked for > 120 seconds).  I
managed to come up with an easy way to reproduce this on my system
(where /dev/sdb is the block device for my USB stick) with:

  while true; do dd if=/dev/zero of=/dev/sdb bs=4M; done

With my reproduction here are the relevant bits from the hung task
detector:

 INFO: task udevd:294 blocked for more than 122 seconds.
 ...
 udevd           D    0   294      1 0x00400008
 Call trace:
  ...
  mutex_lock_nested+0x40/0x50
  __blkdev_get+0x7c/0x3d4
  blkdev_get+0x118/0x138
  blkdev_open+0x94/0xa8
  do_dentry_open+0x268/0x3a0
  vfs_open+0x34/0x40
  path_openat+0x39c/0xdf4
  do_filp_open+0x90/0x10c
  do_sys_open+0x150/0x3c8
  ...

 ...
 Showing all locks held in the system:
 ...
 1 lock held by dd/2798:
  #0: ffffff814ac1a3b8 (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0x50/0x204
 ...
 dd              D    0  2798   2764 0x00400208
 Call trace:
  ...
  schedule+0x8c/0xbc
  io_schedule+0x1c/0x40
  wait_on_page_bit_common+0x238/0x338
  __lock_page+0x5c/0x68
  write_cache_pages+0x194/0x500
  generic_writepages+0x64/0xa4
  blkdev_writepages+0x24/0x30
  do_writepages+0x48/0xa8
  __filemap_fdatawrite_range+0xac/0xd8
  filemap_write_and_wait+0x30/0x84
  __blkdev_put+0x88/0x204
  blkdev_put+0xc4/0xe4
  blkdev_close+0x28/0x38
  __fput+0xe0/0x238
  ____fput+0x1c/0x28
  task_work_run+0xb0/0xe4
  do_notify_resume+0xfc0/0x14bc
  work_pending+0x8/0x14

The problem appears related to the fact that my USB disk is terribly
slow and that I have a lot of RAM in my system to cache things.
Specifically my writes seem to be happening at ~15 MB/s and I've got
~4 GB of RAM in my system that can be used for buffering.  To write 4
GB of buffer to disk thus takes ~4000 MB / ~15 MB/s = ~267 seconds.

The 267 second number is a problem because in __blkdev_put() we call
sync_blockdev() while holding the bd_mutex.  Any other callers who
want the bd_mutex will be blocked for the whole time.

The problem is made worse because I believe blkdev_put() specifically
tells other tasks (namely udev) to go try to access the device at right
around the same time we're going to hold the mutex for a long time.

Putting some traces around this (after disabling the hung task detector),
I could confirm:
 dd:    437.608600: __blkdev_put() right before sync_blockdev() for sdb
 udevd: 437.623901: blkdev_open() right before blkdev_get() for sdb
 dd:    661.468451: __blkdev_put() right after sync_blockdev() for sdb
 udevd: 663.820426: blkdev_open() right after blkdev_get() for sdb

A simple fix for this is to realize that sync_blockdev() works fine if
you're not holding the mutex.  Also, it's not the end of the world if
you sync a little early (though it can have performance impacts).
Thus we can make a guess that we're going to need to do the sync and
then do it without holding the mutex.  We still do one last sync with
the mutex but it should be much, much faster.

With this, my hung task warnings for my test case are gone.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-20 09:31:20 -06:00
Andreas Gruenbacher
7648f939cb nfs: Fix potential posix_acl refcnt leak in nfs3_set_acl
nfs3_set_acl keeps track of the acl it allocated locally to determine if an acl
needs to be released at the end.  This results in a memory leak when the
function allocates an acl as well as a default acl.  Fix by releasing acls
that differ from the acl originally passed into nfs3_set_acl.

Fixes: b7fa0554cf ("[PATCH] NFS: Add support for NFSv3 ACLs")
Reported-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-20 09:58:59 -04:00
Trond Myklebust
4d8948c733 NFS/pnfs: Fix a credential use-after-free issue in pnfs_roc()
If the credential returned by pnfs_prepare_layoutreturn()
does not match the credential of the RPC call, then we do
end up calling pnfs_send_layoutreturn() with that credential,
so don't free it!

Fixes: 44ea8dfce0 ("NFS/pnfs: Reference the layout cred in pnfs_prepare_layoutreturn()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-19 23:53:52 -04:00
Trond Myklebust
7bcc10585b NFS/pnfs: Ensure that _pnfs_return_layout() waits for layoutreturn completion
We require that any outstanding layout return completes before we can
free up the inode so that the layout itself can be freed.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-19 19:27:26 -04:00
Xiaoguang Wang
44575a6731 io_uring: only restore req->work for req that needs do completion
When testing io_uring IORING_FEAT_FAST_POLL feature, I got below panic:
BUG: kernel NULL pointer dereference, address: 0000000000000030
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 5 PID: 2154 Comm: io_uring_echo_s Not tainted 5.6.0+ #359
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:io_wq_submit_work+0xf/0xa0
Code: ff ff ff be 02 00 00 00 e8 ae c9 19 00 e9 58 ff ff ff 66 0f 1f
84 00 00 00 00 00 0f 1f 44 00 00 41 54 49 89 fc 55 53 48 8b 2f <8b>
45 30 48 8d 9d 48 ff ff ff 25 01 01 00 00 83 f8 01 75 07 eb 2a
RSP: 0018:ffffbef543e93d58 EFLAGS: 00010286
RAX: ffffffff84364f50 RBX: ffffa3eb50f046b8 RCX: 0000000000000000
RDX: ffffa3eb0efc1840 RSI: 0000000000000006 RDI: ffffa3eb50f046b8
RBP: 0000000000000000 R08: 00000000fffd070d R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffa3eb50f046b8
R13: ffffa3eb0efc2088 R14: ffffffff85b69be0 R15: ffffa3eb0effa4b8
FS:  00007fe9f69cc4c0(0000) GS:ffffa3eb5ef40000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000030 CR3: 0000000020410000 CR4: 00000000000006e0
Call Trace:
 task_work_run+0x6d/0xa0
 do_exit+0x39a/0xb80
 ? get_signal+0xfe/0xbc0
 do_group_exit+0x47/0xb0
 get_signal+0x14b/0xbc0
 ? __x64_sys_io_uring_enter+0x1b7/0x450
 do_signal+0x2c/0x260
 ? __x64_sys_io_uring_enter+0x228/0x450
 exit_to_usermode_loop+0x87/0xf0
 do_syscall_64+0x209/0x230
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x7fe9f64f8df9
Code: Bad RIP value.

task_work_run calls io_wq_submit_work unexpectedly, it's obvious that
struct callback_head's func member has been changed. After looking into
codes, I found this issue is still due to the union definition:
    union {
        /*
         * Only commands that never go async can use the below fields,
         * obviously. Right now only IORING_OP_POLL_ADD uses them, and
         * async armed poll handlers for regular commands. The latter
         * restore the work, if needed.
         */
        struct {
            struct callback_head	task_work;
            struct hlist_node	hash_node;
            struct async_poll	*apoll;
        };
        struct io_wq_work	work;
    };

When task_work_run has multiple work to execute, the work that calls
io_poll_remove_all() will do req->work restore for  non-poll request
always, but indeed if a non-poll request has been added to a new
callback_head, subsequent callback will call io_async_task_func() to
handle this request, that means we should not do the restore work
for such non-poll request. Meanwhile in io_async_task_func(), we should
drop submit ref when req has been canceled.

Fix both issues.

Fixes: b1f573bd15 ("io_uring: restore req->work when canceling poll request")
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>

Use io_double_put_req()

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-19 13:55:27 -06:00
Linus Torvalds
3e0dea5768 An update for the proc interface of time namespaces: Use symbolic names
instead of clockid numbers. The usability nuisance of numbers was noticed
 by Michael when polishing the man page.
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Merge tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull time namespace fix from Thomas Gleixner:
 "An update for the proc interface of time namespaces: Use symbolic
  names instead of clockid numbers. The usability nuisance of numbers
  was noticed by Michael when polishing the man page"

* tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets
2020-04-19 11:46:21 -07:00
Linus Torvalds
439f1da923 Miscellaneous bug fixes and cleanups for ext4, including a fix for
generic/388 in data=journal mode, removing some BUG_ON's, and cleaning
 up some compiler warnings.
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "Miscellaneous bug fixes and cleanups for ext4, including a fix for
  generic/388 in data=journal mode, removing some BUG_ON's, and cleaning
  up some compiler warnings"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: convert BUG_ON's to WARN_ON's in mballoc.c
  ext4: increase wait time needed before reuse of deleted inode numbers
  ext4: remove set but not used variable 'es' in ext4_jbd2.c
  ext4: remove set but not used variable 'es'
  ext4: do not zeroout extents beyond i_disksize
  ext4: fix return-value types in several function comments
  ext4: use non-movable memory for superblock readahead
  ext4: use matching invalidatepage in ext4_writepage
2020-04-19 11:05:15 -07:00
Linus Torvalds
aee0314bc3 Three small smb3 fixes: two debug related, and one fixing a performance problem with 64K pages
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Merge tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Three small smb3 fixes: two debug related (helping network tracing for
  SMB2 mounts, and the other removing an unintended debug line on
  signing failures), and one fixing a performance problem with 64K
  pages"

* tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: remove overly noisy debug line in signing errors
  cifs: improve read performance for page size 64KB & cache=strict & vers=2.1+
  cifs: dump the session id and keys also for SMB2 sessions
2020-04-19 11:00:27 -07:00
Linus Torvalds
c0d73a868d Fixes for 5.7:
- Fix a partially uninitialized variable.
 - Teach the background gc threads to apply for fsfreeze protection.
 - Fix some scaling problems when multiple threads try to flush the
   filesystem when we're about to hit ENOSPC.
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Merge tag 'xfs-5.7-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:
 "The three commits here fix some livelocks and other clashes with
  fsfreeze, a potential corruption problem, and a minor race between
  processes freeing and allocating space when the filesystem is near
  ENOSPC.

  Summary:

   - Fix a partially uninitialized variable.

   - Teach the background gc threads to apply for fsfreeze protection.

   - Fix some scaling problems when multiple threads try to flush the
     filesystem when we're about to hit ENOSPC"

* tag 'xfs-5.7-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: move inode flush to the sync workqueue
  xfs: fix partially uninitialized structure in xfs_reflink_remap_extent
  xfs: acquire superblock freeze protection on eofblocks scans
2020-04-18 11:46:39 -07:00
Zhiqiang Liu
c4b4c2a78a buffer: remove useless comment and WB_REASON_FREE_MORE_MEM, reason.
free_more_memory func has been completely removed in commit bc48f001de
("buffer: eliminate the need to call free_more_memory() in __getblk_slow()")

So comment and `WB_REASON_FREE_MORE_MEM` reason about free_more_memory
are no longer needed.

Fixes: bc48f001de ("buffer: eliminate the need to call free_more_memory() in __getblk_slow()")
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-17 21:38:11 -06:00
Linus Torvalds
5d286d5ebc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull proc fix from Eric Biederman:
 "While running syzbot happened to spot one more oversight in my rework
  of proc_flush_task.

  The fields proc_self and proc_thread_self were not being reinitialized
  when proc was unmounted, which could cause problems if the mount of
  proc fails"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: Handle umounts cleanly
2020-04-17 12:05:01 -07:00
Linus Torvalds
a2286a449b io_uring-5.7-2020-04-17
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Merge tag 'io_uring-5.7-2020-04-17' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:

 - wrap up the init/setup cleanup (Pavel)

 - fix some issues around deferral sequences (Pavel)

 - fix splice punt check using the wrong struct file member

 - apply poll re-arm logic for pollable retry too

 - pollable retry should honor cancelation

 - fix setup time error handling syzbot reported crash

 - restore work state when poll is canceled

* tag 'io_uring-5.7-2020-04-17' of git://git.kernel.dk/linux-block:
  io_uring: don't count rqs failed after current one
  io_uring: kill already cached timeout.seq_offset
  io_uring: fix cached_sq_head in io_timeout()
  io_uring: only post events in io_poll_remove_all() if we completed some
  io_uring: io_async_task_func() should check and honor cancelation
  io_uring: check for need to re-wait in polled async handling
  io_uring: correct O_NONBLOCK check for splice punt
  io_uring: restore req->work when canceling poll request
  io_uring: move all request init code in one place
  io_uring: keep all sqe->flags in req->flags
  io_uring: early submission req fail code
  io_uring: track mm through current->mm
  io_uring: remove obsolete @mm_fault
2020-04-17 10:12:26 -07:00
Linus Torvalds
c5304dd59b for-5.7-rc1-tag
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Merge tag 'for-5.7-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "A regression fix for a warning caused by running balance and snapshot
  creation in parallel"

* tag 'for-5.7-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix setting last_trans for reloc roots
2020-04-17 10:00:33 -07:00
Chuck Lever
6221f1d9b6 SUNRPC: Fix backchannel RPC soft lockups
Currently, after the forward channel connection goes away,
backchannel operations are causing soft lockups on the server
because call_transmit_status's SOFTCONN logic ignores ENOTCONN.
Such backchannel Calls are aggressively retried until the client
reconnects.

Backchannel Calls should use RPC_TASK_NOCONNECT rather than
RPC_TASK_SOFTCONN. If there is no forward connection, the server is
not capable of establishing a connection back to the client, thus
that backchannel request should fail before the server attempts to
send it. Commit 58255a4e3c ("NFSD: NFSv4 callback client should
use RPC_TASK_SOFTCONN") was merged several years before
RPC_TASK_NOCONNECT was available.

Because setup_callback_client() explicitly sets NOPING, the NFSv4.0
callback connection depends on the first callback RPC to initiate
a connection to the client. Thus NFSv4.0 needs to continue to use
RPC_TASK_SOFTCONN.

Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org> # v4.20+
2020-04-17 12:40:31 -04:00
Greg Kroah-Hartman
2b07021a94 debugfs: remove return value of debugfs_create_u32()
No one checks the return value of debugfs_create_u32(), as it's not
needed, so make the return value void, so that no one tries to do so in
the future.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200416145448.GA1380878@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-17 17:08:50 +02:00
Josef Bacik
aec7db3b13 btrfs: fix setting last_trans for reloc roots
I made a mistake with my previous fix, I assumed that we didn't need to
mess with the reloc roots once we were out of the part of relocation where
we are actually moving the extents.

The subtle thing that I missed is that btrfs_init_reloc_root() also
updates the last_trans for the reloc root when we do
btrfs_record_root_in_trans() for the corresponding fs_root.  I've added a
comment to make sure future me doesn't make this mistake again.

This showed up as a WARN_ON() in btrfs_copy_root() because our
last_trans didn't == the current transid.  This could happen if we
snapshotted a fs root with a reloc root after we set
rc->create_reloc_tree = 0, but before we actually merge the reloc root.

Worth mentioning that the regression produced the following warning
when running snapshot creation and balance in parallel:

  BTRFS info (device sdc): relocating block group 30408704 flags metadata|dup
  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 12823 at fs/btrfs/ctree.c:191 btrfs_copy_root+0x26f/0x430 [btrfs]
  CPU: 0 PID: 12823 Comm: btrfs Tainted: G        W 5.6.0-rc7-btrfs-next-58 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
  RIP: 0010:btrfs_copy_root+0x26f/0x430 [btrfs]
  RSP: 0018:ffffb96e044279b8 EFLAGS: 00010202
  RAX: 0000000000000009 RBX: ffff9da70bf61000 RCX: ffffb96e04427a48
  RDX: ffff9da733a770c8 RSI: ffff9da70bf61000 RDI: ffff9da694163818
  RBP: ffff9da733a770c8 R08: fffffffffffffff8 R09: 0000000000000002
  R10: ffffb96e044279a0 R11: 0000000000000000 R12: ffff9da694163818
  R13: fffffffffffffff8 R14: ffff9da6d2512000 R15: ffff9da714cdac00
  FS:  00007fdeacf328c0(0000) GS:ffff9da735e00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000055a2a5b8a118 CR3: 00000001eed78002 CR4: 00000000003606f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   ? create_reloc_root+0x49/0x2b0 [btrfs]
   ? kmem_cache_alloc_trace+0xe5/0x200
   create_reloc_root+0x8b/0x2b0 [btrfs]
   btrfs_reloc_post_snapshot+0x96/0x5b0 [btrfs]
   create_pending_snapshot+0x610/0x1010 [btrfs]
   create_pending_snapshots+0xa8/0xd0 [btrfs]
   btrfs_commit_transaction+0x4c7/0xc50 [btrfs]
   ? btrfs_mksubvol+0x3cd/0x560 [btrfs]
   btrfs_mksubvol+0x455/0x560 [btrfs]
   __btrfs_ioctl_snap_create+0x15f/0x190 [btrfs]
   btrfs_ioctl_snap_create_v2+0xa4/0xf0 [btrfs]
   ? mem_cgroup_commit_charge+0x6e/0x540
   btrfs_ioctl+0x12d8/0x3760 [btrfs]
   ? do_raw_spin_unlock+0x49/0xc0
   ? _raw_spin_unlock+0x29/0x40
   ? __handle_mm_fault+0x11b3/0x14b0
   ? ksys_ioctl+0x92/0xb0
   ksys_ioctl+0x92/0xb0
   ? trace_hardirqs_off_thunk+0x1a/0x1c
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x5c/0x280
   entry_SYSCALL_64_after_hwframe+0x49/0xbe
  RIP: 0033:0x7fdeabd3bdd7

Fixes: 2abc726ab4 ("btrfs: do not init a reloc root if we aren't relocating")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-17 15:20:08 +02:00
Linus Torvalds
7a56db0299 NFS client bugfix for Linux 5.7
Bugfix:
 - Fix an ABBA spinlock issue in pnfs_update_layout()
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Merge tag 'nfs-for-5.7-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfix from Trond Myklebust:
 "Fix an ABBA spinlock issue in pnfs_update_layout()"

* tag 'nfs-for-5.7-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: Fix an ABBA spinlock issue in pnfs_update_layout()
2020-04-16 18:14:13 -07:00
Linus Torvalds
3fa84bf926 A set of patches for a deadlock on "rbd map" error path and a fix
for invalid pointer dereference and uninitialized variable use on
 asynchronous create and unlink error paths.
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Merge tag 'ceph-for-5.7-rc2' of git://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:

 - a set of patches for a deadlock on "rbd map" error path

 - a fix for invalid pointer dereference and uninitialized variable use
   on asynchronous create and unlink error paths.

* tag 'ceph-for-5.7-rc2' of git://github.com/ceph/ceph-client:
  ceph: fix potential bad pointer deref in async dirops cb's
  rbd: don't mess with a page vector in rbd_notify_op_lock()
  rbd: don't test rbd_dev->opts in rbd_dev_image_release()
  rbd: call rbd_dev_unprobe() after unwatching and flushing notifies
  rbd: avoid a deadlock on header_rwsem when flushing notifies
2020-04-16 10:29:34 -07:00
Steve French
9692ea9d32 smb3: remove overly noisy debug line in signing errors
A dump_stack call for signature related errors can be too noisy
and not of much value in debugging such problems.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
2020-04-16 12:23:40 -05:00
Darrick J. Wong
f0f7a674d4 xfs: move inode flush to the sync workqueue
Move the inode dirty data flushing to a workqueue so that multiple
threads can take advantage of a single thread's flushing work.  The
ratelimiting technique used in bdd4ee4 was not successful, because
threads that skipped the inode flush scan due to ratelimiting would
ENOSPC early, which caused occasional (but noticeable) changes in
behavior and sporadic fstest regressions.

Therefore, make all the writer threads wait on a single inode flush,
which eliminates both the stampeding hordes of flushers and the small
window in which a write could fail with ENOSPC because it lost the
ratelimit race after even another thread freed space.

Fixes: c6425702f2 ("xfs: ratelimit inode flush on buffered write ENOSPC")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-04-16 09:07:42 -07:00
Andrei Vagin
94d440d618 proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets
Michael Kerrisk suggested to replace numeric clock IDs with symbolic names.

Now the content of these files looks like this:
$ cat /proc/774/timens_offsets
monotonic      864000         0
boottime      1728000         0

For setting offsets, both representations of clocks (numeric and symbolic)
can be used.

As for compatibility, it is acceptable to change things as long as
userspace doesn't care. The format of timens_offsets files is very new and
there are no userspace tools yet which rely on this format.

But three projects crun, util-linux and criu rely on the interface of
setting time offsets and this is why it's required to continue supporting
the numeric clock IDs on write.

Fixes: 04a8682a71 ("fs/proc: Introduce /proc/pid/timens_offsets")
Suggested-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200411154031.642557-1-avagin@gmail.com
2020-04-16 12:10:54 +02:00
Eric W. Biederman
4fa3b1c417 proc: Handle umounts cleanly
syzbot writes:
> KASAN: use-after-free Read in dput (2)
>
> proc_fill_super: allocate dentry failed
> ==================================================================
> BUG: KASAN: use-after-free in fast_dput fs/dcache.c:727 [inline]
> BUG: KASAN: use-after-free in dput+0x53e/0xdf0 fs/dcache.c:846
> Read of size 4 at addr ffff88808a618cf0 by task syz-executor.0/8426
>
> CPU: 0 PID: 8426 Comm: syz-executor.0 Not tainted 5.6.0-next-20200412-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> Call Trace:
>  __dump_stack lib/dump_stack.c:77 [inline]
>  dump_stack+0x188/0x20d lib/dump_stack.c:118
>  print_address_description.constprop.0.cold+0xd3/0x315 mm/kasan/report.c:382
>  __kasan_report.cold+0x35/0x4d mm/kasan/report.c:511
>  kasan_report+0x33/0x50 mm/kasan/common.c:625
>  fast_dput fs/dcache.c:727 [inline]
>  dput+0x53e/0xdf0 fs/dcache.c:846
>  proc_kill_sb+0x73/0xf0 fs/proc/root.c:195
>  deactivate_locked_super+0x8c/0xf0 fs/super.c:335
>  vfs_get_super+0x258/0x2d0 fs/super.c:1212
>  vfs_get_tree+0x89/0x2f0 fs/super.c:1547
>  do_new_mount fs/namespace.c:2813 [inline]
>  do_mount+0x1306/0x1b30 fs/namespace.c:3138
>  __do_sys_mount fs/namespace.c:3347 [inline]
>  __se_sys_mount fs/namespace.c:3324 [inline]
>  __x64_sys_mount+0x18f/0x230 fs/namespace.c:3324
>  do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
>  entry_SYSCALL_64_after_hwframe+0x49/0xb3
> RIP: 0033:0x45c889
> Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007ffc1930ec48 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
> RAX: ffffffffffffffda RBX: 0000000001324914 RCX: 000000000045c889
> RDX: 0000000020000140 RSI: 0000000020000040 RDI: 0000000000000000
> RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
> R13: 0000000000000749 R14: 00000000004ca15a R15: 0000000000000013

Looking at the code now that it the internal mount of proc is no
longer used it is possible to unmount proc.   If proc is unmounted
the fields of the pid namespace that were used for filesystem
specific state are not reinitialized.

Which means that proc_self and proc_thread_self can be pointers to
already freed dentries.

The reported user after free appears to be from mounting and
unmounting proc followed by mounting proc again and using error
injection to cause the new root dentry allocation to fail.  This in
turn results in proc_kill_sb running with proc_self and
proc_thread_self still retaining their values from the previous mount
of proc.  Then calling dput on either proc_self of proc_thread_self
will result in double put.  Which KASAN sees as a use after free.

Solve this by always reinitializing the filesystem state stored
in the struct pid_namespace, when proc is unmounted.

Reported-by: syzbot+72868dd424eb66c6b95f@syzkaller.appspotmail.com
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Fixes: 69879c01a0 ("proc: Remove the now unnecessary internal mount of proc")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-04-15 23:52:29 -05:00
Theodore Ts'o
907ea529fc ext4: convert BUG_ON's to WARN_ON's in mballoc.c
If the in-core buddy bitmap gets corrupted (or out of sync with the
block bitmap), issue a WARN_ON and try to recover.  In most cases this
involves skipping trying to allocate out of a particular block group.
We can end up declaring the file system corrupted, which is fair,
since the file system probably should be checked before we proceed any
further.

Link: https://lore.kernel.org/r/20200414035649.293164-1-tytso@mit.edu
Google-Bug-Id: 34811296
Google-Bug-Id: 34639169
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-04-15 23:58:49 -04:00
Theodore Ts'o
a17a9d935d ext4: increase wait time needed before reuse of deleted inode numbers
Current wait times have proven to be too short to protect against inode
reuses that lead to metadata inconsistencies.

Now that we will retry the inode allocation if we can't find any
recently deleted inodes, it's a lot safer to increase the recently
deleted time from 5 seconds to a minute.

Link: https://lore.kernel.org/r/20200414023925.273867-1-tytso@mit.edu
Google-Bug-Id: 36602237
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-04-15 23:58:49 -04:00
Jason Yan
648814111a ext4: remove set but not used variable 'es' in ext4_jbd2.c
Fix the following gcc warning:

fs/ext4/ext4_jbd2.c:341:30: warning: variable 'es' set but not used [-Wunused-but-set-variable]
     struct ext4_super_block *es;
                              ^~

Fixes: 2ea2fc775321 ("ext4: save all error info in save_error_info() and drop ext4_set_errno()")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200402034759.29957-1-yanaijie@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-04-15 23:58:49 -04:00
Jason Yan
05ca87c149 ext4: remove set but not used variable 'es'
Fix the following gcc warning:

fs/ext4/super.c:599:27: warning: variable 'es' set but not used [-Wunused-but-set-variable]
  struct ext4_super_block *es;
                           ^~
Fixes: 2ea2fc775321 ("ext4: save all error info in save_error_info() and drop ext4_set_errno()")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200402033939.25303-1-yanaijie@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-04-15 23:58:49 -04:00
Jan Kara
801674f34e ext4: do not zeroout extents beyond i_disksize
We do not want to create initialized extents beyond end of file because
for e2fsck it is impossible to distinguish them from a case of corrupted
file size / extent tree and so it complains like:

Inode 12, i_size is 147456, should be 163840.  Fix? no

Code in ext4_ext_convert_to_initialized() and
ext4_split_convert_extents() try to make sure it does not create
initialized extents beyond inode size however they check against
inode->i_size which is wrong. They should instead check against
EXT4_I(inode)->i_disksize which is the current inode size on disk.
That's what e2fsck is going to see in case of crash before all dirty
data is written. This bug manifests as generic/456 test failure (with
recent enough fstests where fsx got fixed to properly pass
FALLOC_KEEP_SIZE_FL flags to the kernel) when run with dioread_lock
mount option.

CC: stable@vger.kernel.org
Fixes: 21ca087a38 ("ext4: Do not zero out uninitialized extents beyond i_size")
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20200331105016.8674-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-04-15 23:58:48 -04:00
Josh Triplett
9033783c8c ext4: fix return-value types in several function comments
The documentation comments for ext4_read_block_bitmap_nowait and
ext4_read_inode_bitmap describe them as returning NULL on error, but
they return an ERR_PTR on error; update the documentation to match.

The documentation comment for ext4_wait_block_bitmap describes it as
returning 1 on error, but it returns -errno on error; update the
documentation to match.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Ritesh Harani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/60a3f4996f4932c45515aaa6b75ca42f2a78ec9b.1585512514.git.josh@joshtriplett.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-04-15 23:58:48 -04:00
Roman Gushchin
d87f639258 ext4: use non-movable memory for superblock readahead
Since commit a8ac900b81 ("ext4: use non-movable memory for the
superblock") buffers for ext4 superblock were allocated using
the sb_bread_unmovable() helper which allocated buffer heads
out of non-movable memory blocks. It was necessarily to not block
page migrations and do not cause cma allocation failures.

However commit 85c8f176a6 ("ext4: preload block group descriptors")
broke this by introducing pre-reading of the ext4 superblock.
The problem is that __breadahead() is using __getblk() underneath,
which allocates buffer heads out of movable memory.

It resulted in page migration failures I've seen on a machine
with an ext4 partition and a preallocated cma area.

Fix this by introducing sb_breadahead_unmovable() and
__breadahead_gfp() helpers which use non-movable memory for buffer
head allocations and use them for the ext4 superblock readahead.

Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Fixes: 85c8f176a6 ("ext4: preload block group descriptors")
Signed-off-by: Roman Gushchin <guro@fb.com>
Link: https://lore.kernel.org/r/20200229001411.128010-1-guro@fb.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-04-15 23:58:48 -04:00
yangerkun
c2a559bc0e ext4: use matching invalidatepage in ext4_writepage
Run generic/388 with journal data mode sometimes may trigger the warning
in ext4_invalidatepage. Actually, we should use the matching invalidatepage
in ext4_writepage.

Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200226041002.13914-1-yangerkun@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-04-15 23:58:48 -04:00
Jones Syue
1f641d9410 cifs: improve read performance for page size 64KB & cache=strict & vers=2.1+
Found a read performance issue when linux kernel page size is 64KB.
If linux kernel page size is 64KB and mount options cache=strict &
vers=2.1+, it does not support cifs_readpages(). Instead, it is using
cifs_readpage() and cifs_read() with maximum read IO size 16KB, which is
much slower than read IO size 1MB when negotiated SMB 2.1+. Since modern
SMB server supported SMB 2.1+ and Max Read Size can reach more than 64KB
(for example 1MB ~ 8MB), this patch check max_read instead of maxBuf to
determine whether server support readpages() and improve read performance
for page size 64KB & cache=strict & vers=2.1+, and for SMB1 it is more
cleaner to initialize server->max_read to server->maxBuf.

The client is a linux box with linux kernel 4.2.8,
page size 64KB (CONFIG_ARM64_64K_PAGES=y),
cpu arm 1.7GHz, and use mount.cifs as smb client.
The server is another linux box with linux kernel 4.2.8,
share a file '10G.img' with size 10GB,
and use samba-4.7.12 as smb server.

The client mount a share from the server with different
cache options: cache=strict and cache=none,
mount -tcifs //<server_ip>/Public /cache_strict -overs=3.0,cache=strict,username=<xxx>,password=<yyy>
mount -tcifs //<server_ip>/Public /cache_none -overs=3.0,cache=none,username=<xxx>,password=<yyy>

The client download a 10GbE file from the server across 1GbE network,
dd if=/cache_strict/10G.img of=/dev/null bs=1M count=10240
dd if=/cache_none/10G.img of=/dev/null bs=1M count=10240

Found that cache=strict (without patch) is slower read throughput and
smaller read IO size than cache=none.
cache=strict (without patch): read throughput 40MB/s, read IO size is 16KB
cache=strict (with patch): read throughput 113MB/s, read IO size is 1MB
cache=none: read throughput 109MB/s, read IO size is 1MB

Looks like if page size is 64KB,
cifs_set_ops() would use cifs_addr_ops_smallbuf instead of cifs_addr_ops,

	/* check if server can support readpages */
	if (cifs_sb_master_tcon(cifs_sb)->ses->server->maxBuf <
			PAGE_SIZE + MAX_CIFS_HDR_SIZE)
		inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
	else
		inode->i_data.a_ops = &cifs_addr_ops;

maxBuf is came from 2 places, SMB2_negotiate() and CIFSSMBNegotiate(),
(SMB2_MAX_BUFFER_SIZE is 64KB)
SMB2_negotiate():
	/* set it to the maximum buffer size value we can send with 1 credit */
	server->maxBuf = min_t(unsigned int, le32_to_cpu(rsp->MaxTransactSize),
			       SMB2_MAX_BUFFER_SIZE);
CIFSSMBNegotiate():
	server->maxBuf = le32_to_cpu(pSMBr->MaxBufferSize);

Page size 64KB and cache=strict lead to read_pages() use cifs_readpage()
instead of cifs_readpages(), and then cifs_read() using maximum read IO
size 16KB, which is much slower than maximum read IO size 1MB.
(CIFSMaxBufSize is 16KB by default)

	/* FIXME: set up handlers for larger reads and/or convert to async */
	rsize = min_t(unsigned int, cifs_sb->rsize, CIFSMaxBufSize);
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Jones Syue <jonessyue@qnap.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-15 21:15:11 -05:00
Ronnie Sahlberg
f560cda91b cifs: dump the session id and keys also for SMB2 sessions
We already dump these keys for SMB3, lets also dump it for SMB2
sessions so that we can use the session key in wireshark to check and validate
that the signatures are correct.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-04-15 21:15:03 -05:00
Pavel Begunkov
31af27c7cc io_uring: don't count rqs failed after current one
When checking for draining with __req_need_defer(), it tries to match
how many requests were sent before a current one with number of already
completed. Dropped SQEs are included in req->sequence, and they won't
ever appear in CQ. To compensate for that, __req_need_defer() substracts
ctx->cached_sq_dropped.
However, what it should really use is number of SQEs dropped __before__
the current one. In other words, any submitted request shouldn't
shouldn't affect dequeueing from the drain queue of previously submitted
ones.

Instead of saving proper ctx->cached_sq_dropped in each request,
substract from req->sequence it at initialisation, so it includes number
of properly submitted requests.

note: it also changes behaviour of timeouts, but
1. it's already diverge from the description because of using SQ
2. the description is ambiguous regarding dropped SQEs

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-14 19:16:59 -06:00
Pavel Begunkov
b55ce73200 io_uring: kill already cached timeout.seq_offset
req->timeout.count and req->io->timeout.seq_offset store the same value,
which is sqe->off. Kill the second one

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-14 19:16:57 -06:00
Pavel Begunkov
22cad1585c io_uring: fix cached_sq_head in io_timeout()
io_timeout() can be executed asynchronously by a worker and without
holding ctx->uring_lock

1. using ctx->cached_sq_head there is racy there
2. it should count events from a moment of timeout's submission, but
not execution

Use req->sequence.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-14 19:16:55 -06:00
Linus Torvalds
6cc9306b8f for-5.7-rc1-tag
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Merge tag 'for-5.7-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "We have a few regressions and one fix for stable:

   - revert fsync optimization

   - fix lost i_size update

   - fix a space accounting leak

   - build fix, add back definition of a deprecated ioctl flag

   - fix search condition for old roots in relocation"

* tag 'for-5.7-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: re-instantiate the removed BTRFS_SUBVOL_CREATE_ASYNC definition
  btrfs: fix reclaim counter leak of space_info objects
  btrfs: make full fsyncs always operate on the entire file again
  btrfs: fix lost i_size update after cloning inline extent
  btrfs: check commit root generation in should_ignore_root
2020-04-14 11:51:30 -07:00
Jens Axboe
8e2e1faf28 io_uring: only post events in io_poll_remove_all() if we completed some
syzbot reports this crash:

BUG: unable to handle page fault for address: ffffffffffffffe8
PGD f96e17067 P4D f96e17067 PUD f96e19067 PMD 0
Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
CPU: 55 PID: 211750 Comm: trinity-c127 Tainted: G    B        L    5.7.0-rc1-next-20200413 #4
Hardware name: HP ProLiant DL380 Gen9/ProLiant DL380 Gen9, BIOS P89 04/12/2017
RIP: 0010:__wake_up_common+0x98/0x290
el/sched/wait.c:87
Code: 40 4d 8d 78 e8 49 8d 7f 18 49 39 fd 0f 84 80 00 00 00 e8 6b bd 2b 00 49 8b 5f 18 45 31 e4 48 83 eb 18 4c 89 ff e8 08 bc 2b 00 <45> 8b 37 41 f6 c6 04 75 71 49 8d 7f 10 e8 46 bd 2b 00 49 8b 47 10
RSP: 0018:ffffc9000adbfaf0 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffffffffffe8 RCX: ffffffffaa9636b8
RDX: 0000000000000003 RSI: dffffc0000000000 RDI: ffffffffffffffe8
RBP: ffffc9000adbfb40 R08: fffffbfff582c5fd R09: fffffbfff582c5fd
R10: ffffffffac162fe3 R11: fffffbfff582c5fc R12: 0000000000000000
R13: ffff888ef82b0960 R14: ffffc9000adbfb80 R15: ffffffffffffffe8
FS:  00007fdcba4c4740(0000) GS:ffff889033780000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffe8 CR3: 0000000f776a0004 CR4: 00000000001606e0
Call Trace:
 __wake_up_common_lock+0xea/0x150
ommon_lock at kernel/sched/wait.c:124
 ? __wake_up_common+0x290/0x290
 ? lockdep_hardirqs_on+0x16/0x2c0
 __wake_up+0x13/0x20
 io_cqring_ev_posted+0x75/0xe0
v_posted at fs/io_uring.c:1160
 io_ring_ctx_wait_and_kill+0x1c0/0x2f0
l at fs/io_uring.c:7305
 io_uring_create+0xa8d/0x13b0
 ? io_req_defer_prep+0x990/0x990
 ? __kasan_check_write+0x14/0x20
 io_uring_setup+0xb8/0x130
 ? io_uring_create+0x13b0/0x13b0
 ? check_flags.part.28+0x220/0x220
 ? lockdep_hardirqs_on+0x16/0x2c0
 __x64_sys_io_uring_setup+0x31/0x40
 do_syscall_64+0xcc/0xaf0
 ? syscall_return_slowpath+0x580/0x580
 ? lockdep_hardirqs_off+0x1f/0x140
 ? entry_SYSCALL_64_after_hwframe+0x3e/0xb3
 ? trace_hardirqs_off_caller+0x3a/0x150
 ? trace_hardirqs_off_thunk+0x1a/0x1c
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x7fdcb9dd76ed
Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 6b 57 2c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe7fd4e4f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 00000000000001a9 RCX: 00007fdcb9dd76ed
RDX: fffffffffffffffc RSI: 0000000000000000 RDI: 0000000000005d54
RBP: 00000000000001a9 R08: 0000000e31d3caa7 R09: 0082400004004000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000002
R13: 00007fdcb842e058 R14: 00007fdcba4c46c0 R15: 00007fdcb842e000
Modules linked in: bridge stp llc nfnetlink cn brd vfat fat ext4 crc16 mbcache jbd2 loop kvm_intel kvm irqbypass intel_cstate intel_uncore dax_pmem intel_rapl_perf dax_pmem_core ip_tables x_tables xfs sd_mod tg3 firmware_class libphy hpsa scsi_transport_sas dm_mirror dm_region_hash dm_log dm_mod [last unloaded: binfmt_misc]
CR2: ffffffffffffffe8
---[ end trace f9502383d57e0e22 ]---
RIP: 0010:__wake_up_common+0x98/0x290
Code: 40 4d 8d 78 e8 49 8d 7f 18 49 39 fd 0f 84 80 00 00 00 e8 6b bd 2b 00 49 8b 5f 18 45 31 e4 48 83 eb 18 4c 89 ff e8 08 bc 2b 00 <45> 8b 37 41 f6 c6 04 75 71 49 8d 7f 10 e8 46 bd 2b 00 49 8b 47 10
RSP: 0018:ffffc9000adbfaf0 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffffffffffe8 RCX: ffffffffaa9636b8
RDX: 0000000000000003 RSI: dffffc0000000000 RDI: ffffffffffffffe8
RBP: ffffc9000adbfb40 R08: fffffbfff582c5fd R09: fffffbfff582c5fd
R10: ffffffffac162fe3 R11: fffffbfff582c5fc R12: 0000000000000000
R13: ffff888ef82b0960 R14: ffffc9000adbfb80 R15: ffffffffffffffe8
FS:  00007fdcba4c4740(0000) GS:ffff889033780000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffe8 CR3: 0000000f776a0004 CR4: 00000000001606e0
Kernel panic - not syncing: Fatal exception
Kernel Offset: 0x29800000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
---[ end Kernel panic - not syncing: Fatal exception ]—

which is due to error injection (or allocation failure) preventing the
rings from being setup. On shutdown, we attempt to remove any pending
requests, and for poll request, we call io_cqring_ev_posted() when we've
killed poll requests. However, since the rings aren't setup, we won't
find any poll requests. Make the calling of io_cqring_ev_posted()
dependent on actually having completed requests. This fixes this setup
corner case, and removes spurious calls if we remove poll requests and
don't find any.

Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-13 17:05:14 -06:00
Trond Myklebust
fbf4bcc9a8 NFS: Fix an ABBA spinlock issue in pnfs_update_layout()
We need to drop the inode spinlock while calling nfs4_select_rw_stateid(),
since nfs4_copy_delegation_stateid() could take the delegation lock.
Note that it is safe to do this, since all other calls to
pnfs_update_layout() for that inode will find themselves blocked by
the lock we hold on NFS_LAYOUT_FIRST_LAYOUTGET.

Fixes: fc51b1cf39 ("NFS: Beware when dereferencing the delegation cred")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-13 15:55:21 -04:00
Jeff Layton
2a575f138d ceph: fix potential bad pointer deref in async dirops cb's
The new async dirops callback routines can pass ERR_PTR values to
ceph_mdsc_free_path, which could cause an oops. Make ceph_mdsc_free_path
ignore ERR_PTR values. Also, ensure that the pr_warn messages look sane
even if ceph_mdsc_build_path fails.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-04-13 19:33:47 +02:00
Jens Axboe
2bae047ec9 io_uring: io_async_task_func() should check and honor cancelation
If the request has been marked as canceled, don't try and issue it.
Instead just fill a canceled event and finish the request.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-13 11:22:52 -06:00
Jens Axboe
74ce6ce43d io_uring: check for need to re-wait in polled async handling
We added this for just the regular poll requests in commit a6ba632d2c
("io_uring: retry poll if we got woken with non-matching mask"), we
should do the same for the poll handler used pollable async requests.
Move the re-wait check and arm into a helper, and call it from
io_async_task_func() as well.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-13 11:09:12 -06:00
Darrick J. Wong
c142932c29 xfs: fix partially uninitialized structure in xfs_reflink_remap_extent
In the reflink extent remap function, it turns out that uirec (the block
mapping corresponding only to the part of the passed-in mapping that got
unmapped) was not fully initialized.  Specifically, br_state was not
being copied from the passed-in struct to the uirec.  This could lead to
unpredictable results such as the reflinked mapping being marked
unwritten in the destination file.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-04-13 08:00:23 -07:00
Brian Foster
4b674b9ac8 xfs: acquire superblock freeze protection on eofblocks scans
The filesystem freeze sequence in XFS waits on any background
eofblocks or cowblocks scans to complete before the filesystem is
quiesced. At this point, the freezer has already stopped the
transaction subsystem, however, which means a truncate or cowblock
cancellation in progress is likely blocked in transaction
allocation. This results in a deadlock between freeze and the
associated scanner.

Fix this problem by holding superblock write protection across calls
into the block reapers. Since protection for background scans is
acquired from the workqueue task context, trylock to avoid a similar
deadlock between freeze and blocking on the write lock.

Fixes: d6b636ebb1 ("xfs: halt auto-reclamation activities while rebuilding rmap")
Reported-by: Paul Furtado <paulfurtado91@gmail.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-04-13 08:00:19 -07:00
Vasily Averin
e1e8399eee nfsd: memory corruption in nfsd4_lock()
New struct nfsd4_blocked_lock allocated in find_or_allocate_block()
does not initialized nbl_list and nbl_lru.
If conflock allocation fails rollback can call list_del_init()
access uninitialized fields and corrupt memory.

v2: just initialize nbl_list and nbl_lru right after nbl allocation.

Fixes: 76d348fadf ("nfsd: have nfsd4_lock use blocking locks for v4.1+ lock")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-04-13 10:28:21 -04:00
David Howells
40fc81027f afs: Fix afs_d_validate() to set the right directory version
If a dentry's version is somewhere between invalid_before and the current
directory version, we should be setting it forward to the current version,
not backwards to the invalid_before version.  Note that we're only doing
this at all because dentry::d_fsdata isn't large enough on a 32-bit system.

Fix this by using a separate variable for invalid_before so that we don't
accidentally clobber the current dir version.

Fixes: a4ff7401fb ("afs: Keep track of invalid-before version for dentry coherency")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
2105c2820d afs: Fix race between post-modification dir edit and readdir/d_revalidate
AFS directories are retained locally as a structured file, with lookup
being effected by a local search of the file contents.  When a modification
(such as mkdir) happens, the dir file content is modified locally rather
than redownloading the directory.

The directory contents are accessed in a number of ways, with a number of
different locks schemes:

 (1) Download of contents - dvnode->validate_lock/write in afs_read_dir().

 (2) Lookup and readdir - dvnode->validate_lock/read in afs_dir_iterate(),
     downgrading from (1) if necessary.

 (3) d_revalidate of child dentry - dvnode->validate_lock/read in
     afs_do_lookup_one() downgrading from (1) if necessary.

 (4) Edit of dir after modification - page locks on individual dir pages.

Unfortunately, because (4) uses different locking scheme to (1) - (3),
nothing protects against the page being scanned whilst the edit is
underway.  Even download is not safe as it doesn't lock the pages - relying
instead on the validate_lock to serialise as a whole (the theory being that
directory contents are treated as a block and always downloaded as a
block).

Fix this by write-locking dvnode->validate_lock around the edits.  Care
must be taken in the rename case as there may be two different dirs - but
they need not be locked at the same time.  In any case, once the lock is
taken, the directory version must be rechecked, and the edit skipped if a
later version has been downloaded by revalidation (there can't have been
any local changes because the VFS holds the inode lock, but there can have
been remote changes).

Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
3efe55b09a afs: Fix length of dump of bad YFSFetchStatus record
Fix the length of the dump of a bad YFSFetchStatus record.  The function
was copied from the AFS version, but the YFS variant contains bigger fields
and extra information, so expand the dump to match.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
b98f0ec91c afs: Fix rename operation status delivery
The afs_deliver_fs_rename() and yfs_deliver_fs_rename() functions both only
decode the second file status returned unless the parent directories are
different - unfortunately, this means that the xdr pointer isn't advanced
and the volsync record will be read incorrectly in such an instance.

Fix this by always decoding the second status into the second
status/callback block which wasn't being used if the dirs were the same.

The afs_update_dentry_version() calls that update the directory data
version numbers on the dentries can then unconditionally use the second
status record as this will always reflect the state of the destination dir
(the two records will be identical if the destination dir is the same as
the source dir)

Fixes: 260a980317 ("[AFS]: Add "directory write" support.")
Fixes: 30062bd13e ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
3e0d9892c0 afs: Fix decoding of inline abort codes from version 1 status records
If we're decoding an AFSFetchStatus record and we see that the version is 1
and the abort code is set and we're expecting inline errors, then we store
the abort code and ignore the remaining status record (which is correct),
but we don't set the flag to say we got a valid abort code.

This can affect operation of YFS.RemoveFile2 when removing a file and the
operation of {,Y}FS.InlineBulkStatus when prospectively constructing or
updating of a set of inodes during a lookup.

Fix this to indicate the reception of a valid abort code.

Fixes: a38a75581e ("afs: Fix unlink to handle YFS.RemoveFile2 better")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
c72057b56f afs: Fix missing XDR advance in xdr_decode_{AFS,YFS}FSFetchStatus()
If we receive a status record that has VNOVNODE set in the abort field,
xdr_decode_AFSFetchStatus() and xdr_decode_YFSFetchStatus() don't advance
the XDR pointer, thereby corrupting anything subsequent decodes from the
same block of data.

This has the potential to affect AFS.InlineBulkStatus and
YFS.InlineBulkStatus operation, but probably doesn't since the status
records are extracted as individual blocks of data and the buffer pointer
is reset between blocks.

It does affect YFS.RemoveFile2 operation, corrupting the volsync record -
though that is not currently used.

Other operations abort the entire operation rather than returning an error
inline, in which case there is no decoding to be done.

Fix this by unconditionally advancing the xdr pointer.

Fixes: 684b0f68cf ("afs: Fix AFSFetchStatus decoder to provide OpenAFS compatibility")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
Jens Axboe
8835758085 io_uring: correct O_NONBLOCK check for splice punt
The splice file punt check uses file->f_mode to check for O_NONBLOCK,
but it should be checking file->f_flags. This leads to punting even
for files that have O_NONBLOCK set, which isn't necessary. This equates
to checking for FMODE_PATH, which will never be set on the fd in
question.

Fixes: 7d67af2c01 ("io_uring: add splice(2) support")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-12 21:16:01 -06:00
Linus Torvalds
4119bf9f1d 10 smb fixes most RDMA (smbdirect) related, also add experimental support for swap over SMB3 mounts, and also adds fix which improves performance of signed connections
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Merge tag '5.7-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Ten cifs/smb fixes:

   - five RDMA (smbdirect) related fixes

   - add experimental support for swap over SMB3 mounts

   - also a fix which improves performance of signed connections"

* tag '5.7-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: enable swap on SMB3 mounts
  smb3: change noisy error message to FYI
  smb3: smbdirect support can be configured by default
  cifs: smbd: Do not schedule work to send immediate packet on every receive
  cifs: smbd: Properly process errors on ib_post_send
  cifs: Allocate crypto structures on the fly for calculating signatures of incoming packets
  cifs: smbd: Update receive credits before sending and deal with credits roll back on failure before sending
  cifs: smbd: Check send queue size before posting a send
  cifs: smbd: Merge code to track pending packets
  cifs: ignore cached share root handle closing errors
2020-04-12 09:41:01 -07:00
Linus Torvalds
50bda5faa6 NFS client bugfix for Linux 5.7
Bugfix:
 - Fix an RCU read lock leakage in pnfs_alloc_ds_commits_list()
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Merge tag 'nfs-for-5.7-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfix from Trond Myklebust:
 "Fix an RCU read lock leakage in pnfs_alloc_ds_commits_list()"

* tag 'nfs-for-5.7-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  pNFS: Fix RCU lock leakage
2020-04-12 09:39:47 -07:00
Xiaoguang Wang
b1f573bd15 io_uring: restore req->work when canceling poll request
When running liburing test case 'accept', I got below warning:
RED: Invalid credentials
RED: At include/linux/cred.h:285
RED: Specified credentials: 00000000d02474a0
RED: ->magic=4b, put_addr=000000005b4f46e9
RED: ->usage=-1699227648, subscr=-25693
RED: ->*uid = { 256,-25693,-25693,65534 }
RED: ->*gid = { 0,-1925859360,-1789740800,-1827028688 }
RED: ->security is 00000000258c136e
eneral protection fault, probably for non-canonical address 0xdead4ead00000000: 0000 [#1] SMP PTI
PU: 21 PID: 2037 Comm: accept Not tainted 5.6.0+ #318
ardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014
IP: 0010:dump_invalid_creds+0x16f/0x184
ode: 48 8b 83 88 00 00 00 48 3d ff 0f 00 00 76 29 48 89 c2 81 e2 00 ff ff ff 48
81 fa 00 6b 6b 6b 74 17 5b 48 c7 c7 4b b1 10 8e 5d <8b> 50 04 41 5c 8b 30 41 5d
e9 67 e3 04 00 5b 5d 41 5c 41 5d c3 0f
SP: 0018:ffffacc1039dfb38 EFLAGS: 00010087
AX: dead4ead00000000 RBX: ffff9ba39319c100 RCX: 0000000000000007
DX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e10b14b
BP: ffffffff8e108476 R08: 0000000000000000 R09: 0000000000000001
10: 0000000000000000 R11: ffffacc1039df9e5 R12: 000000009552b900
13: 000000009319c130 R14: ffff9ba39319c100 R15: 0000000000000246
S:  00007f96b2bfc4c0(0000) GS:ffff9ba39f340000(0000) knlGS:0000000000000000
S:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
R2: 0000000000401870 CR3: 00000007db7a4000 CR4: 00000000000006e0
all Trace:
__invalid_creds+0x48/0x4a
__io_req_aux_free+0x2e8/0x3b0
? io_poll_remove_one+0x2a/0x1d0
__io_free_req+0x18/0x200
io_free_req+0x31/0x350
io_poll_remove_one+0x17f/0x1d0
io_poll_cancel.isra.80+0x6c/0x80
io_async_find_and_cancel+0x111/0x120
io_issue_sqe+0x181/0x10e0
? __lock_acquire+0x552/0xae0
? lock_acquire+0x8e/0x310
? fs_reclaim_acquire.part.97+0x5/0x30
__io_queue_sqe.part.100+0xc4/0x580
? io_submit_sqes+0x751/0xbd0
? rcu_read_lock_sched_held+0x32/0x40
io_submit_sqes+0x9ba/0xbd0
? __x64_sys_io_uring_enter+0x2b2/0x460
? __x64_sys_io_uring_enter+0xaf/0x460
? find_held_lock+0x2d/0x90
? __x64_sys_io_uring_enter+0x111/0x460
__x64_sys_io_uring_enter+0x2d7/0x460
do_syscall_64+0x5a/0x230
entry_SYSCALL_64_after_hwframe+0x49/0xb3

After looking into codes, it turns out that this issue is because we didn't
restore the req->work, which is changed in io_arm_poll_handler(), req->work
is a union with below struct:
	struct {
		struct callback_head	task_work;
		struct hlist_node	hash_node;
		struct async_poll	*apoll;
	};
If we forget to restore, members in struct io_wq_work would be invalid,
restore the req->work to fix this issue.

Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>

Get rid of not needed 'need_restore' variable.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-12 08:46:50 -06:00
Pavel Begunkov
ef4ff58110 io_uring: move all request init code in one place
Requests initialisation is scattered across several functions, namely
io_init_req(), io_submit_sqes(), io_submit_sqe(). Put it
in io_init_req() for better data locality and code clarity.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-12 08:46:50 -06:00
Pavel Begunkov
dea3b49c7f io_uring: keep all sqe->flags in req->flags
It's a good idea to not read sqe->flags twice, as it's prone to security
bugs. Instead of passing it around, embeed them in req->flags. It's
already so except for IOSQE_IO_LINK.
1. rename former REQ_F_LINK -> REQ_F_LINK_HEAD
2. introduce and copy REQ_F_LINK, which mimics IO_IOSQE_LINK

And leave req_set_fail_links() using new REQ_F_LINK, because it's more
sensible.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-12 08:46:49 -06:00
Pavel Begunkov
1d4240cc9e io_uring: early submission req fail code
Having only one place for cleaning up a request after a link assembly/
submission failure will play handy in the future. At least it allows
to remove duplicated cleanup sequence.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-12 08:46:44 -06:00
Pavel Begunkov
bf9c2f1cdc io_uring: track mm through current->mm
As a preparation for extracting request init bits, remove self-coded mm
tracking from io_submit_sqes(), but rely on current->mm. It's more
convenient, than passing this piece of state in other functions.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-12 08:46:30 -06:00
Pavel Begunkov
dccc587f6c io_uring: remove obsolete @mm_fault
If io_submit_sqes() can't grab an mm, it fails and exits right away.
There is no need to track the fact of the failure. Remove @mm_fault.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-12 08:46:30 -06:00
Trond Myklebust
27d231c0c6 pNFS: Fix RCU lock leakage
Another brown paper bag moment. pnfs_alloc_ds_commits_list() is leaking
the RCU lock.

Fixes: a9901899b6 ("pNFS: Add infrastructure for cleaning up per-layout commit structures")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-11 11:42:35 -04:00
Linus Torvalds
5b8b9d0c6d Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:

 - Almost all of the rest of MM (memcg, slab-generic, slab, pagealloc,
   gup, hugetlb, pagemap, memremap)

 - Various other things (hfs, ocfs2, kmod, misc, seqfile)

* akpm: (34 commits)
  ipc/util.c: sysvipc_find_ipc() should increase position index
  kernel/gcov/fs.c: gcov_seq_next() should increase position index
  fs/seq_file.c: seq_read(): add info message about buggy .next functions
  drivers/dma/tegra20-apb-dma.c: fix platform_get_irq.cocci warnings
  change email address for Pali Rohár
  selftests: kmod: test disabling module autoloading
  selftests: kmod: fix handling test numbers above 9
  docs: admin-guide: document the kernel.modprobe sysctl
  fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once()
  kmod: make request_module() return an error when autoloading is disabled
  mm/memremap: set caching mode for PCI P2PDMA memory to WC
  mm/memory_hotplug: add pgprot_t to mhp_params
  powerpc/mm: thread pgprot_t through create_section_mapping()
  x86/mm: introduce __set_memory_prot()
  x86/mm: thread pgprot_t through init_memory_mapping()
  mm/memory_hotplug: rename mhp_restrictions to mhp_params
  mm/memory_hotplug: drop the flags field from struct mhp_restrictions
  mm/special: create generic fallbacks for pte_special() and pte_mkspecial()
  mm/vma: introduce VM_ACCESS_FLAGS
  mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS
  ...
2020-04-10 17:57:48 -07:00
Linus Torvalds
4e4bdcfa21 orangefs: a fix and two cleanups and a merge conflict
Fix: Christoph Hellwig noticed that some logic I added to
      orangefs_file_read_iter introduced a race condition, so he
      sent a reversion patch. I had to modify his patch since
      reverting at this point broke Orangefs.
 
 Cleanup 1: Christoph Hellwig noticed that we were doing some unnecessary
            work in orangefs_flush, so he sent in a patch that removed
            the un-needed code.
 
 Cleanup 2: Al Viro told me he had trouble building Orangefs. Orangefs
            should be easy to build, even for Al :-). I looked back
            at the test server build notes in orangefs.txt, just in case
            that's where the trouble really is, and found a couple of
            typos and made a couple of clarifications.
 
 Merge Conflict: Stephen Rothwell reported that my modifications to
                 orangefs.txt caused a merge conflict with orangefs.rst
                 in Linux Next. I wasn't sure what to do, so I asked,
                 and Jonathan Corbet said not to worry about it and
                 just to report it to Linus.
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Merge tag 'for-linus-5.7-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux

Pull orangefs updates from Mike Marshall:
 "A fix and two cleanups.

  Fix:

   - Christoph Hellwig noticed that some logic I added to
     orangefs_file_read_iter introduced a race condition, so he sent a
     reversion patch. I had to modify his patch since reverting at this
     point broke Orangefs.

  Cleanups:

   - Christoph Hellwig noticed that we were doing some unnecessary work
     in orangefs_flush, so he sent in a patch that removed the un-needed
     code.

   - Al Viro told me he had trouble building Orangefs. Orangefs should
     be easy to build, even for Al :-).

     I looked back at the test server build notes in orangefs.txt, just
     in case that's where the trouble really is, and found a couple of
     typos and made a couple of clarifications"

* tag 'for-linus-5.7-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
  orangefs: clarify build steps for test server in orangefs.txt
  orangefs: don't mess with I_DIRTY_TIMES in orangefs_flush
  orangefs: get rid of knob code...
2020-04-10 17:50:01 -07:00
Vasily Averin
3bfa7e141b fs/seq_file.c: seq_read(): add info message about buggy .next functions
Patch series "seq_file .next functions should increase position index".

In Aug 2018 NeilBrown noticed commit 1f4aace60b ("fs/seq_file.c:
simplify seq_file iteration code and interface")

"Some ->next functions do not increment *pos when they return NULL...
Note that such ->next functions are buggy and should be fixed.  A simple
demonstration is dd if=/proc/swaps bs=1000 skip=1 Choose any block size
larger than the size of /proc/swaps.  This will always show the whole
last line of /proc/swaps"

Described problem is still actual.  If you make lseek into middle of
last output line following read will output end of last line and whole
last line once again.

  $ dd if=/proc/swaps bs=1  # usual output
  Filename				Type		Size	Used	Priority
  /dev/dm-0                             partition	4194812	97536	-2
  104+0 records in
  104+0 records out
  104 bytes copied

  $ dd if=/proc/swaps bs=40 skip=1    # last line was generated twice
  dd: /proc/swaps: cannot skip to specified offset
  v/dm-0                                partition	4194812	97536	-2
  /dev/dm-0                             partition	4194812	97536	-2
  3+1 records in
  3+1 records out
  131 bytes copied

There are lot of other affected files, I've found 30+ including
/proc/net/ip_tables_matches and /proc/sysvipc/*

I've sent patches into maillists of affected subsystems already, this
patch-set fixes the problem in files related to pstore, tracing, gcov,
sysvipc and other subsystems processed via linux-kernel@ mailing list
directly

https://bugzilla.kernel.org/show_bug.cgi?id=206283

This patch (of 4):

Add debug code to seq_read() to detect missed or out-of-tree incorrect
.next seq_file functions.

[akpm@linux-foundation.org: s/pr_info/pr_info_ratelimited/, per Qian Cai]
https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: NeilBrown <neilb@suse.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Waiman Long <longman@redhat.com>
Link: http://lkml.kernel.org/r/244674e5-760c-86bd-d08a-047042881748@virtuozzo.com
Link: http://lkml.kernel.org/r/7c24087c-e280-e580-5b0c-0cdaeb14cd18@virtuozzo.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:22 -07:00
Pali Rohár
149ed3d404 change email address for Pali Rohár
For security reasons I stopped using gmail account and kernel address is
now up-to-date alias to my personal address.

People periodically send me emails to address which they found in source
code of drivers, so this change reflects state where people can contact
me.

[ Added .mailmap entry as per Joe Perches  - Linus ]
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Link: http://lkml.kernel.org/r/20200307104237.8199-1-pali@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:22 -07:00
Eric Biggers
26c5d78c97 fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once()
After request_module(), nothing is stopping the module from being
unloaded until someone takes a reference to it via try_get_module().

The WARN_ONCE() in get_fs_type() is thus user-reachable, via userspace
running 'rmmod' concurrently.

Since WARN_ONCE() is for kernel bugs only, not for user-reachable
situations, downgrade this warning to pr_warn_once().

Keep it printed once only, since the intent of this warning is to detect
a bug in modprobe at boot time.  Printing the warning more than once
wouldn't really provide any useful extra information.

Fixes: 41124db869 ("fs: warn in case userspace lied about modprobe return")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jessica Yu <jeyu@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: NeilBrown <neilb@suse.com>
Cc: <stable@vger.kernel.org>		[4.13+]
Link: http://lkml.kernel.org/r/20200312202552.241885-3-ebiggers@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:22 -07:00
Changwei Ge
783fda856e ocfs2: no need try to truncate file beyond i_size
Linux fallocate(2) with FALLOC_FL_PUNCH_HOLE mode set, its offset can
exceed the inode size.  Ocfs2 now doesn't allow that offset beyond inode
size.  This restriction is not necessary and violates fallocate(2)
semantics.

If fallocate(2) offset is beyond inode size, just return success and do
nothing further.

Otherwise, ocfs2 will crash the kernel.

  kernel BUG at fs/ocfs2//alloc.c:7264!
   ocfs2_truncate_inline+0x20f/0x360 [ocfs2]
   ocfs2_remove_inode_range+0x23c/0xcb0 [ocfs2]
   __ocfs2_change_file_space+0x4a5/0x650 [ocfs2]
   ocfs2_fallocate+0x83/0xa0 [ocfs2]
   vfs_fallocate+0x148/0x230
   SyS_fallocate+0x48/0x80
   do_syscall_64+0x79/0x170

Signed-off-by: Changwei Ge <chge@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200407082754.17565-1-chge@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Simon Gander
25efb2ffdf hfsplus: fix crash and filesystem corruption when deleting files
When removing files containing extended attributes, the hfsplus driver may
remove the wrong entries from the attributes b-tree, causing major
filesystem damage and in some cases even kernel crashes.

To remove a file, all its extended attributes have to be removed as well.
The driver does this by looking up all keys in the attributes b-tree with
the cnid of the file.  Each of these entries then gets deleted using the
key used for searching, which doesn't contain the attribute's name when it
should.  Since the key doesn't contain the name, the deletion routine will
not find the correct entry and instead remove the one in front of it.  If
parent nodes have to be modified, these become corrupt as well.  This
causes invalid links and unsorted entries that not even macOS's fsck_hfs
is able to fix.

To fix this, modify the search key before an entry is deleted from the
attributes b-tree by copying the found entry's key into the search key,
therefore ensuring that the correct entry gets removed from the tree.

Signed-off-by: Simon Gander <simon@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Anton Altaparmakov <anton@tuxera.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200327155541.1521-1-simon@tuxera.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:20 -07:00
Linus Torvalds
87ad46e601 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull proc fix from Eric Biederman:
 "A brown paper bag slipped through my proc changes, and syzcaller
  caught it when the code ended up in your tree.

  I have opted to fix it the simplest cleanest way I know how, so there
  is no reasonable chance for the bug to repeat"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: Use a dedicated lock in struct pid
2020-04-10 12:59:56 -07:00
Steve French
4e8aea30f7 smb3: enable swap on SMB3 mounts
Add experimental support for allowing a swap file to be on an SMB3
mount.  There are use cases where swapping over a secure network
filesystem is preferable. In some cases there are no local
block devices large enough, and network block devices can be
hard to setup and secure.  And in some cases there are no
local block devices at all (e.g. with the recent addition of
remote boot over SMB3 mounts).

There are various enhancements that can be added later e.g.:
- doing a mandatory byte range lock over the swapfile (until
the Linux VFS is modified to notify the file system that an open
is for a swapfile, when the file can be opened "DENY_ALL" to prevent
others from opening it).
- pinning more buffers in the underlying transport to minimize memory
allocations in the TCP stack under the fs
- documenting how to create ACLs (on the server) to secure the
swapfile (or adding additional tools to cifs-utils to make it easier)

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-04-10 13:32:32 -05:00
Linus Torvalds
172edde960 io_uring-5.7-2020-04-09
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Merge tag 'io_uring-5.7-2020-04-09' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:
 "Here's a set of fixes that either weren't quite ready for the first,
  or came about from some intensive testing on memcached with 350K+
  sockets.

  Summary:

   - Fixes for races or deadlocks around poll handling

   - Don't double account fixed files against RLIMIT_NOFILE

   - IORING_OP_OPENAT LFS fix

   - Poll retry handling (Bijan)

   - Missing finish_wait() for SQPOLL (Hillf)

   - Cleanup/split of io_kiocb alloc vs ctx references (Pavel)

   - Fixed file unregistration and init fixes (Xiaoguang)

   - Various little fixes (Xiaoguang, Pavel, Colin)"

* tag 'io_uring-5.7-2020-04-09' of git://git.kernel.dk/linux-block:
  io_uring: punt final io_ring_ctx wait-and-free to workqueue
  io_uring: fix fs cleanup on cqe overflow
  io_uring: don't read user-shared sqe flags twice
  io_uring: remove req init from io_get_req()
  io_uring: alloc req only after getting sqe
  io_uring: simplify io_get_sqring
  io_uring: do not always copy iovec in io_req_map_rw()
  io_uring: ensure openat sets O_LARGEFILE if needed
  io_uring: initialize fixed_file_data lock
  io_uring: remove redundant variable pointer nxt and io_wq_assign_next call
  io_uring: fix ctx refcounting in io_submit_sqes()
  io_uring: process requests completed with -EAGAIN on poll list
  io_uring: remove bogus RLIMIT_NOFILE check in file registration
  io_uring: use io-wq manager as backup task if task is exiting
  io_uring: grab task reference for poll requests
  io_uring: retry poll if we got woken with non-matching mask
  io_uring: add missing finish_wait() in io_sq_thread()
  io_uring: refactor file register/unregister/update handling
2020-04-10 10:02:21 -07:00
Linus Torvalds
8c3c07439e (More) new code for 5.7:
- Validate the realtime geometry in the superblock when mounting
 - Refactor a bunch of tricky flag handling in the log code
 - Flush the CIL more judiciously so that we don't wait until there are
   millions of log items consuming a lot of memory.
 - Throttle transaction commits to prevent the xfs frontend from flooding
   the CIL with too many log items.
 - Account metadata buffers correctly for memory reclaim.
 - Mark slabs properly for memory reclaim.  These should help reclaim run
   more effectively when XFS is using a lot of memory.
 - Don't write a garbage log record at unmount time if we're trying to
   trigger summary counter recalculation at next mount.
 - Don't block the AIL on locked dquot/inode buffers; instead trigger its
   backoff mechanism to give the lock holder a chance to finish up.
 - Ratelimit writeback flushing when buffered writes encounter ENOSPC.
 - Other minor cleanups.
 - Make reflink a synchronous operation when the fs is mounted with wsync
   or sync, which means that now we force the log to disk to record the
   changes.
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Merge tag 'xfs-5.7-merge-12' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull more xfs updates from Darrick Wong:
 "As promised last week, this batch changes how xfs interacts with
  memory reclaim; how the log batches and throttles log items; how hard
  writes near ENOSPC will try to squeeze more space out of the
  filesystem; and hopefully fix the last of the umount hangs after a
  catastrophic failure.

  Summary:

   - Validate the realtime geometry in the superblock when mounting

   - Refactor a bunch of tricky flag handling in the log code

   - Flush the CIL more judiciously so that we don't wait until there
     are millions of log items consuming a lot of memory.

   - Throttle transaction commits to prevent the xfs frontend from
     flooding the CIL with too many log items.

   - Account metadata buffers correctly for memory reclaim.

   - Mark slabs properly for memory reclaim. These should help reclaim
     run more effectively when XFS is using a lot of memory.

   - Don't write a garbage log record at unmount time if we're trying to
     trigger summary counter recalculation at next mount.

   - Don't block the AIL on locked dquot/inode buffers; instead trigger
     its backoff mechanism to give the lock holder a chance to finish
     up.

   - Ratelimit writeback flushing when buffered writes encounter ENOSPC.

   - Other minor cleanups.

   - Make reflink a synchronous operation when the fs is mounted with
     wsync or sync, which means that now we force the log to disk to
     record the changes"

* tag 'xfs-5.7-merge-12' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (26 commits)
  xfs: reflink should force the log out if mounted with wsync
  xfs: factor out a new xfs_log_force_inode helper
  xfs: fix inode number overflow in ifree cluster helper
  xfs: remove redundant variable assignment in xfs_symlink()
  xfs: ratelimit inode flush on buffered write ENOSPC
  xfs: return locked status of inode buffer on xfsaild push
  xfs: trylock underlying buffer on dquot flush
  xfs: remove unnecessary ternary from xfs_create
  xfs: don't write a corrupt unmount record to force summary counter recalc
  xfs: factor inode lookup from xfs_ifree_cluster
  xfs: tail updates only need to occur when LSN changes
  xfs: factor common AIL item deletion code
  xfs: correctly acount for reclaimable slabs
  xfs: Improve metadata buffer reclaim accountability
  xfs: don't allow log IO to be throttled
  xfs: Throttle commits on delayed background CIL push
  xfs: Lower CIL flush limit for large logs
  xfs: remove some stale comments from the log code
  xfs: refactor unmount record writing
  xfs: merge xlog_commit_record with xlog_write_done
  ...
2020-04-10 09:54:26 -07:00
Jens Axboe
85faa7b834 io_uring: punt final io_ring_ctx wait-and-free to workqueue
We can't reliably wait in io_ring_ctx_wait_and_kill(), since the
task_works list isn't ordered (in fact it's LIFO ordered). We could
either fix this with a separate task_works list for io_uring work, or
just punt the wait-and-free to async context. This ensures that
task_work that comes in while we're shutting down is processed
correctly. If we don't go async, we could have work past the fput()
work for the ring that depends on work that won't be executed until
after we're done with the wait-and-free. But as this operation is
blocking, it'll never get a chance to run.

This was reproduced with hundreds of thousands of sockets running
memcached, haven't been able to reproduce this synthetically.

Reported-by: Dan Melnic <dmm@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-09 18:45:27 -06:00
Steve French
1dc94b7381 smb3: change noisy error message to FYI
The noisy posix error message in readdir was supposed
to be an FYI (not enabled by default)
  CIFS VFS: XXX dev 66306, reparse 0, mode 755

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-04-09 13:28:24 -05:00
Linus Torvalds
e4da01d833 powerpc updates for 5.7 #2
- A fix for a crash in machine check handling on pseries (ie. guests)
 
  - A small series to make it possible to disable CONFIG_COMPAT, and turn it off
    by default for ppc64le where it's not used.
 
  - A few other miscellaneous fixes and small improvements.
 
 Thanks to:
   Alexey Kardashevskiy, Anju T Sudhakar, Arnd Bergmann, Christophe Leroy, Dan
   Carpenter, Ganesh Goudar, Geert Uytterhoeven, Geoff Levand, Mahesh Salgaonkar,
   Markus Elfring, Michal Suchanek, Nicholas Piggin, Stephen Boyd, Wen Xiong.
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Merge tag 'powerpc-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull more powerpc updates from Michael Ellerman:
 "The bulk of this is the series to make CONFIG_COMPAT user-selectable,
  it's been around for a long time but was blocked behind the
  syscall-in-C series.

  Plus there's also a few fixes and other minor things.

  Summary:

   - A fix for a crash in machine check handling on pseries (ie. guests)

   - A small series to make it possible to disable CONFIG_COMPAT, and
     turn it off by default for ppc64le where it's not used.

   - A few other miscellaneous fixes and small improvements.

  Thanks to: Alexey Kardashevskiy, Anju T Sudhakar, Arnd Bergmann,
  Christophe Leroy, Dan Carpenter, Ganesh Goudar, Geert Uytterhoeven,
  Geoff Levand, Mahesh Salgaonkar, Markus Elfring, Michal Suchanek,
  Nicholas Piggin, Stephen Boyd, Wen Xiong"

* tag 'powerpc-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  selftests/powerpc: Always build the tm-poison test 64-bit
  powerpc: Improve ppc_save_regs()
  Revert "powerpc/64: irq_work avoid interrupt when called with hardware irqs enabled"
  powerpc/time: Replace <linux/clk-provider.h> by <linux/of_clk.h>
  powerpc/pseries/ddw: Extend upper limit for huge DMA window for persistent memory
  powerpc/perf: split callchain.c by bitness
  powerpc/64: Make COMPAT user-selectable disabled on littleendian by default.
  powerpc/64: make buildable without CONFIG_COMPAT
  powerpc/perf: consolidate valid_user_sp -> invalid_user_sp
  powerpc/perf: consolidate read_user_stack_32
  powerpc: move common register copy functions from signal_32.c to signal.c
  powerpc: Add back __ARCH_WANT_SYS_LLSEEK macro
  powerpc/ps3: Set CONFIG_UEVENT_HELPER=y in ps3_defconfig
  powerpc/ps3: Remove an unneeded NULL check
  powerpc/ps3: Remove duplicate error message
  powerpc/powernv: Re-enable imc trace-mode in kernel
  powerpc/perf: Implement a global lock to avoid races between trace, core and thread imc events.
  powerpc/pseries: Fix MCE handling on pseries
  selftests/eeh: Skip ahci adapters
  powerpc/64s: Fix doorbell wakeup msgclr optimisation
2020-04-09 11:01:42 -07:00
Eric W. Biederman
63f818f46a proc: Use a dedicated lock in struct pid
syzbot wrote:
> ========================================================
> WARNING: possible irq lock inversion dependency detected
> 5.6.0-syzkaller #0 Not tainted
> --------------------------------------------------------
> swapper/1/0 just changed the state of lock:
> ffffffff898090d8 (tasklist_lock){.+.?}-{2:2}, at: send_sigurg+0x9f/0x320 fs/fcntl.c:840
> but this lock took another, SOFTIRQ-unsafe lock in the past:
>  (&pid->wait_pidfd){+.+.}-{2:2}
>
>
> and interrupts could create inverse lock ordering between them.
>
>
> other info that might help us debug this:
>  Possible interrupt unsafe locking scenario:
>
>        CPU0                    CPU1
>        ----                    ----
>   lock(&pid->wait_pidfd);
>                                local_irq_disable();
>                                lock(tasklist_lock);
>                                lock(&pid->wait_pidfd);
>   <Interrupt>
>     lock(tasklist_lock);
>
>  *** DEADLOCK ***
>
> 4 locks held by swapper/1/0:

The problem is that because wait_pidfd.lock is taken under the tasklist
lock.  It must always be taken with irqs disabled as tasklist_lock can be
taken from interrupt context and if wait_pidfd.lock was already taken this
would create a lock order inversion.

Oleg suggested just disabling irqs where I have added extra calls to
wait_pidfd.lock.  That should be safe and I think the code will eventually
do that.  It was rightly pointed out by Christian that sharing the
wait_pidfd.lock was a premature optimization.

It is also true that my pre-merge window testing was insufficient.  So
remove the premature optimization and give struct pid a dedicated lock of
it's own for struct pid things.  I have verified that lockdep sees all 3
paths where we take the new pid->lock and lockdep does not complain.

It is my current day dream that one day pid->lock can be used to guard the
task lists as well and then the tasklist_lock won't need to be held to
deliver signals.  That will require taking pid->lock with irqs disabled.

Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/lkml/00000000000011d66805a25cd73f@google.com/
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Reported-by: syzbot+343f75cdeea091340956@syzkaller.appspotmail.com
Reported-by: syzbot+832aabf700bc3ec920b9@syzkaller.appspotmail.com
Reported-by: syzbot+f675f964019f884dbd0f@syzkaller.appspotmail.com
Reported-by: syzbot+a9fb1457d720a55d6dc5@syzkaller.appspotmail.com
Fixes: 7bc3e6e55a ("proc: Use a list of inodes to flush from proc")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-04-09 12:15:35 -05:00