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67639 commits

Author SHA1 Message Date
Filipe Manana
a6703c7115 btrfs: fix crash after non-aligned direct IO write with O_DSYNC
Whenever we attempt to do a non-aligned direct IO write with O_DSYNC, we
end up triggering an assertion and crashing. Example reproducer:

  $ cat test.sh
  #!/bin/bash

  DEV=/dev/sdj
  MNT=/mnt/sdj

  mkfs.btrfs -f $DEV > /dev/null
  mount $DEV $MNT

  # Do a direct IO write with O_DSYNC into a non-aligned range...
  xfs_io -f -d -s -c "pwrite -S 0xab -b 64K 1111 64K" $MNT/foobar

  umount $MNT

When running the reproducer an assertion fails and produces the following
trace:

  [ 2418.403134] assertion failed: !current->journal_info || flush != BTRFS_RESERVE_FLUSH_DATA, in fs/btrfs/space-info.c:1467
  [ 2418.403745] ------------[ cut here ]------------
  [ 2418.404306] kernel BUG at fs/btrfs/ctree.h:3286!
  [ 2418.404862] invalid opcode: 0000 [#2] PREEMPT SMP DEBUG_PAGEALLOC PTI
  [ 2418.405451] CPU: 1 PID: 64705 Comm: xfs_io Tainted: G      D           5.10.15-btrfs-next-87 #1
  [ 2418.406026] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  [ 2418.407228] RIP: 0010:assertfail.constprop.0+0x18/0x26 [btrfs]
  [ 2418.407835] Code: e6 48 c7 (...)
  [ 2418.409078] RSP: 0018:ffffb06080d13c98 EFLAGS: 00010246
  [ 2418.409696] RAX: 000000000000006c RBX: ffff994c1debbf08 RCX: 0000000000000000
  [ 2418.410302] RDX: 0000000000000000 RSI: 0000000000000027 RDI: 00000000ffffffff
  [ 2418.410904] RBP: ffff994c21770000 R08: 0000000000000000 R09: 0000000000000000
  [ 2418.411504] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000010000
  [ 2418.412111] R13: ffff994c22198400 R14: ffff994c21770000 R15: 0000000000000000
  [ 2418.412713] FS:  00007f54fd7aff00(0000) GS:ffff994d35200000(0000) knlGS:0000000000000000
  [ 2418.413326] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [ 2418.413933] CR2: 000056549596d000 CR3: 000000010b928003 CR4: 0000000000370ee0
  [ 2418.414528] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [ 2418.415109] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [ 2418.415669] Call Trace:
  [ 2418.416254]  btrfs_reserve_data_bytes.cold+0x22/0x22 [btrfs]
  [ 2418.416812]  btrfs_check_data_free_space+0x4c/0xa0 [btrfs]
  [ 2418.417380]  btrfs_buffered_write+0x1b0/0x7f0 [btrfs]
  [ 2418.418315]  btrfs_file_write_iter+0x2a9/0x770 [btrfs]
  [ 2418.418920]  new_sync_write+0x11f/0x1c0
  [ 2418.419430]  vfs_write+0x2bb/0x3b0
  [ 2418.419972]  __x64_sys_pwrite64+0x90/0xc0
  [ 2418.420486]  do_syscall_64+0x33/0x80
  [ 2418.420979]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [ 2418.421486] RIP: 0033:0x7f54fda0b986
  [ 2418.421981] Code: 48 c7 c0 (...)
  [ 2418.423019] RSP: 002b:00007ffc40569c38 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
  [ 2418.423547] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f54fda0b986
  [ 2418.424075] RDX: 0000000000010000 RSI: 000056549595e000 RDI: 0000000000000003
  [ 2418.424596] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000400
  [ 2418.425119] R10: 0000000000000400 R11: 0000000000000246 R12: 00000000ffffffff
  [ 2418.425644] R13: 0000000000000400 R14: 0000000000010000 R15: 0000000000000000
  [ 2418.426148] Modules linked in: btrfs blake2b_generic (...)
  [ 2418.429540] ---[ end trace ef2aeb44dc0afa34 ]---

1) At btrfs_file_write_iter() we set current->journal_info to
   BTRFS_DIO_SYNC_STUB;

2) We then call __btrfs_direct_write(), which calls btrfs_direct_IO();

3) We can't do the direct IO write because it starts at a non-aligned
   offset (1111). So at btrfs_direct_IO() we return -EINVAL (coming from
   check_direct_IO() which does the alignment check), but we leave
   current->journal_info set to BTRFS_DIO_SYNC_STUB - we only clear it
   at btrfs_dio_iomap_begin(), because we assume we always get there;

4) Then at __btrfs_direct_write() we see that the attempt to do the
   direct IO write was not successful, 0 bytes written, so we fallback
   to a buffered write by calling btrfs_buffered_write();

5) There we call btrfs_check_data_free_space() which in turn calls
   btrfs_alloc_data_chunk_ondemand() and that calls
   btrfs_reserve_data_bytes() with flush == BTRFS_RESERVE_FLUSH_DATA;

6) Then at btrfs_reserve_data_bytes() we have current->journal_info set to
   BTRFS_DIO_SYNC_STUB, therefore not NULL, and flush has the value
   BTRFS_RESERVE_FLUSH_DATA, triggering the second assertion:

  int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
                               enum btrfs_reserve_flush_enum flush)
  {
      struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
      int ret;

      ASSERT(flush == BTRFS_RESERVE_FLUSH_DATA ||
             flush == BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE);
      ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_DATA);
  (...)

So fix that by setting the journal to NULL whenever check_direct_IO()
returns a failure.

This bug only affects 5.10 kernels, and the regression was introduced in
5.10-rc1 by commit 0eb79294db ("btrfs: dio iomap DSYNC workaround").
The bug does not exist in 5.11 kernels due to commit ecfdc08b8c
("btrfs: remove dio iomap DSYNC workaround"), which depends on a large
patchset that went into the merge window for 5.11. So this is a fix only
for 5.10.x stable kernels, as there are people hitting this bug.

Fixes: 0eb79294db ("btrfs: dio iomap DSYNC workaround")
CC: stable@vger.kernel.org # 5.10 (and only 5.10)
Acked-by: David Sterba <dsterba@suse.com>
Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1181605
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-23 15:53:25 +01:00
David Sterba
aa0fd921d2 btrfs: fix backport of 2175bf57dc in 5.10.13
There's a mistake in backport of upstream commit 2175bf57dc ("btrfs:
fix possible free space tree corruption with online conversion") as
5.10.13 commit 2175bf57dc.

The enum value BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED has been added to the
wrong enum set, colliding with value of BTRFS_FS_QUOTA_ENABLE. This
could cause problems during the tree conversion, where the quotas
wouldn't be set up properly but the related code executed anyway due to
the bit set.

Link: https://lore.kernel.org/linux-btrfs/20210219111741.95DD.409509F4@e16-tech.com
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
CC: stable@vger.kernel.org # 5.10.13+
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-23 15:53:25 +01:00
Miklos Szeredi
e5c376c41a ovl: expand warning in ovl_d_real()
commit cef4cbff06 upstream.

There was a syzbot report with this warning but insufficient information...

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-17 11:02:30 +01:00
Amir Goldstein
116826d615 ovl: skip getxattr of security labels
[ Upstream commit 03fedf9359 ]

When inode has no listxattr op of its own (e.g. squashfs) vfs_listxattr
calls the LSM inode_listsecurity hooks to list the xattrs that LSMs will
intercept in inode_getxattr hooks.

When selinux LSM is installed but not initialized, it will list the
security.selinux xattr in inode_listsecurity, but will not intercept it
in inode_getxattr.  This results in -ENODATA for a getxattr call for an
xattr returned by listxattr.

This situation was manifested as overlayfs failure to copy up lower
files from squashfs when selinux is built-in but not initialized,
because ovl_copy_xattr() iterates the lower inode xattrs by
vfs_listxattr() and vfs_getxattr().

ovl_copy_xattr() skips copy up of security labels that are indentified by
inode_copy_up_xattr LSM hooks, but it does that after vfs_getxattr().
Since we are not going to copy them, skip vfs_getxattr() of the security
labels.

Reported-by: Michael Labriola <michael.d.labriola@gmail.com>
Tested-by: Michael Labriola <michael.d.labriola@gmail.com>
Link: https://lore.kernel.org/linux-unionfs/2nv9d47zt7.fsf@aldarion.sourceruckus.org/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-17 11:02:22 +01:00
Miklos Szeredi
cbb9404a50 ovl: perform vfs_getxattr() with mounter creds
[ Upstream commit 554677b972 ]

The vfs_getxattr() in ovl_xattr_set() is used to check whether an xattr
exist on a lower layer file that is to be removed.  If the xattr does not
exist, then no need to copy up the file.

This call of vfs_getxattr() wasn't wrapped in credential override, and this
is probably okay.  But for consitency wrap this instance as well.

Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-17 11:02:22 +01:00
Seth Forshee
8c5864d21e tmpfs: disallow CONFIG_TMPFS_INODE64 on alpha
commit ad69c389ec upstream.

As with s390, alpha is a 64-bit architecture with a 32-bit ino_t.  With
CONFIG_TMPFS_INODE64=y tmpfs mounts will get 64-bit inode numbers and
display "inode64" in the mount options, whereas passing "inode64" in the
mount options will fail.  This leads to erroneous behaviours such as
this:

  # mkdir mnt
  # mount -t tmpfs nodev mnt
  # mount -o remount,rw mnt
  mount: /home/ubuntu/mnt: mount point not mounted or bad option.

Prevent CONFIG_TMPFS_INODE64 from being selected on alpha.

Link: https://lkml.kernel.org/r/20210208215726.608197-1-seth.forshee@canonical.com
Fixes: ea3271f719 ("tmpfs: support 64-bit inums per-sb")
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Chris Down <chris@chrisdown.name>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: <stable@vger.kernel.org>	[5.9+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-17 11:02:21 +01:00
Seth Forshee
b03a0d5cc2 tmpfs: disallow CONFIG_TMPFS_INODE64 on s390
commit b85a7a8bb5 upstream.

Currently there is an assumption in tmpfs that 64-bit architectures also
have a 64-bit ino_t.  This is not true on s390 which has a 32-bit ino_t.
With CONFIG_TMPFS_INODE64=y tmpfs mounts will get 64-bit inode numbers
and display "inode64" in the mount options, but passing the "inode64"
mount option will fail.  This leads to the following behavior:

  # mkdir mnt
  # mount -t tmpfs nodev mnt
  # mount -o remount,rw mnt
  mount: /home/ubuntu/mnt: mount point not mounted or bad option.

As mount sees "inode64" in the mount options and thus passes it in the
options for the remount.

So prevent CONFIG_TMPFS_INODE64 from being selected on s390.

Link: https://lkml.kernel.org/r/20210205230620.518245-1-seth.forshee@canonical.com
Fixes: ea3271f719 ("tmpfs: support 64-bit inums per-sb")
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Chris Down <chris@chrisdown.name>
Cc: Hugh Dickins <hughd@google.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: <stable@vger.kernel.org>	[5.9+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-17 11:02:21 +01:00
Phillip Lougher
bddcce15cd squashfs: add more sanity checks in xattr id lookup
commit 506220d2ba upstream.

Sysbot has reported a warning where a kmalloc() attempt exceeds the
maximum limit.  This has been identified as corruption of the xattr_ids
count when reading the xattr id lookup table.

This patch adds a number of additional sanity checks to detect this
corruption and others.

1. It checks for a corrupted xattr index read from the inode.  This could
   be because the metadata block is uncompressed, or because the
   "compression" bit has been corrupted (turning a compressed block
   into an uncompressed block).  This would cause an out of bounds read.

2. It checks against corruption of the xattr_ids count.  This can either
   lead to the above kmalloc failure, or a smaller than expected
   table to be read.

3. It checks the contents of the index table for corruption.

[phillip@squashfs.org.uk: fix checkpatch issue]
  Link: https://lkml.kernel.org/r/270245655.754655.1612770082682@webmail.123-reg.co.uk

Link: https://lkml.kernel.org/r/20210204130249.4495-5-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reported-by: syzbot+2ccea6339d368360800d@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:55:19 +01:00
Phillip Lougher
5e22b39b37 squashfs: add more sanity checks in inode lookup
commit eabac19e40 upstream.

Sysbot has reported an "slab-out-of-bounds read" error which has been
identified as being caused by a corrupted "ino_num" value read from the
inode.  This could be because the metadata block is uncompressed, or
because the "compression" bit has been corrupted (turning a compressed
block into an uncompressed block).

This patch adds additional sanity checks to detect this, and the
following corruption.

1. It checks against corruption of the inodes count.  This can either
   lead to a larger table to be read, or a smaller than expected
   table to be read.

   In the case of a too large inodes count, this would often have been
   trapped by the existing sanity checks, but this patch introduces
   a more exact check, which can identify too small values.

2. It checks the contents of the index table for corruption.

[phillip@squashfs.org.uk: fix checkpatch issue]
  Link: https://lkml.kernel.org/r/527909353.754618.1612769948607@webmail.123-reg.co.uk

Link: https://lkml.kernel.org/r/20210204130249.4495-4-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reported-by: syzbot+04419e3ff19d2970ea28@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:55:18 +01:00
Phillip Lougher
6634147f51 squashfs: add more sanity checks in id lookup
commit f37aa4c736 upstream.

Sysbot has reported a number of "slab-out-of-bounds reads" and
"use-after-free read" errors which has been identified as being caused
by a corrupted index value read from the inode.  This could be because
the metadata block is uncompressed, or because the "compression" bit has
been corrupted (turning a compressed block into an uncompressed block).

This patch adds additional sanity checks to detect this, and the
following corruption.

1. It checks against corruption of the ids count.  This can either
   lead to a larger table to be read, or a smaller than expected
   table to be read.

   In the case of a too large ids count, this would often have been
   trapped by the existing sanity checks, but this patch introduces
   a more exact check, which can identify too small values.

2. It checks the contents of the index table for corruption.

Link: https://lkml.kernel.org/r/20210204130249.4495-3-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reported-by: syzbot+b06d57ba83f604522af2@syzkaller.appspotmail.com
Reported-by: syzbot+c021ba012da41ee9807c@syzkaller.appspotmail.com
Reported-by: syzbot+5024636e8b5fd19f0f19@syzkaller.appspotmail.com
Reported-by: syzbot+bcbc661df46657d0fa4f@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:55:18 +01:00
Phillip Lougher
ff3a75bda7 squashfs: avoid out of bounds writes in decompressors
commit e812cbbbbb upstream.

Patch series "Squashfs: fix BIO migration regression and add sanity checks".

Patch [1/4] fixes a regression introduced by the "migrate from
ll_rw_block usage to BIO" patch, which has produced a number of
Sysbot/Syzkaller reports.

Patches [2/4], [3/4], and [4/4] fix a number of filesystem corruption
issues which have produced Sysbot reports in the id, inode and xattr
lookup code.

Each patch has been tested against the Sysbot reproducers using the
given kernel configuration.  They have the appropriate "Reported-by:"
lines added.

Additionally, all of the reproducer filesystems are indirectly fixed by
patch [4/4] due to the fact they all have xattr corruption which is now
detected there.

Additional testing with other configurations and architectures (32bit,
big endian), and normal filesystems has also been done to trap any
inadvertent regressions caused by the additional sanity checks.

This patch (of 4):

This is a regression introduced by the patch "migrate from ll_rw_block
usage to BIO".

Sysbot/Syskaller has reported a number of "out of bounds writes" and
"unable to handle kernel paging request in squashfs_decompress" errors
which have been identified as a regression introduced by the above
patch.

Specifically, the patch removed the following sanity check

        if (length < 0 || length > output->length ||
		(index + length) > msblk->bytes_used)

This check did two things:

1. It ensured any reads were not beyond the end of the filesystem

2. It ensured that the "length" field read from the filesystem
   was within the expected maximum length.  Without this any
   corrupted values can over-run allocated buffers.

Link: https://lkml.kernel.org/r/20210204130249.4495-1-phillip@squashfs.org.uk
Link: https://lkml.kernel.org/r/20210204130249.4495-2-phillip@squashfs.org.uk
Fixes: 93e72b3c61 ("squashfs: migrate from ll_rw_block usage to BIO")
Reported-by: syzbot+6fba78f99b9afd4b5634@syzkaller.appspotmail.com
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Philippe Liard <pliard@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:55:17 +01:00
Joachim Henke
237ee28818 nilfs2: make splice write available again
commit a35d8f016e upstream.

Since 5.10, splice() or sendfile() to NILFS2 return EINVAL.  This was
caused by commit 36e2c7421f ("fs: don't allow splice read/write
without explicit ops").

This patch initializes the splice_write field in file_operations, like
most file systems do, to restore the functionality.

Link: https://lkml.kernel.org/r/1612784101-14353-1-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Joachim Henke <joachim.henke@t-systems.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>	[5.10+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:55:16 +01:00
Trond Myklebust
ff557bf971 pNFS/NFSv4: Improve rejection of out-of-order layouts
[ Upstream commit d29b468da4 ]

If a layoutget ends up being reordered w.r.t. a layoutreturn, e.g. due
to a layoutget-on-open not knowing a priori which file to lock, then we
must assume the layout is no longer being considered valid state by the
server.
Incrementally improve our ability to reject such states by using the
cached old stateid in conjunction with the plh_barrier to try to
identify them.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13 13:55:06 +01:00
Trond Myklebust
386b142945 pNFS/NFSv4: Try to return invalid layout in pnfs_layout_process()
[ Upstream commit 08bd8dbe88 ]

If the server returns a new stateid that does not match the one in our
cache, then try to return the one we hold instead of just invalidating
it on the client side. This ensures that both client and server will
agree that the stateid is invalid.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13 13:55:05 +01:00
Pavel Begunkov
5592eae784 io_uring: drop mm/files between task_work_submit
[ Upstream commit aec18a57ed ]

Since SQPOLL task can be shared and so task_work entries can be a mix of
them, we need to drop mm and files before trying to issue next request.

Cc: stable@vger.kernel.org # 5.10+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:55:01 +01:00
Pavel Begunkov
88dbd085a5 io_uring: reinforce cancel on flush during exit
[ Upstream commit 3a7efd1ad2 ]

What 84965ff8a8 ("io_uring: if we see flush on exit, cancel related tasks")
really wants is to cancel all relevant REQ_F_INFLIGHT requests reliably.
That can be achieved by io_uring_cancel_files(), but we'll miss it
calling io_uring_cancel_task_requests(files=NULL) from io_uring_flush(),
because it will go through __io_uring_cancel_task_requests().

Just always call io_uring_cancel_files() during cancel, it's good enough
for now.

Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:55:01 +01:00
Pavel Begunkov
aa435155d3 io_uring: fix sqo ownership false positive warning
[ Upstream commit 70b2c60d37 ]

WARNING: CPU: 0 PID: 21359 at fs/io_uring.c:9042
    io_uring_cancel_task_requests+0xe55/0x10c0 fs/io_uring.c:9042
Call Trace:
 io_uring_flush+0x47b/0x6e0 fs/io_uring.c:9227
 filp_close+0xb4/0x170 fs/open.c:1295
 close_files fs/file.c:403 [inline]
 put_files_struct fs/file.c:418 [inline]
 put_files_struct+0x1cc/0x350 fs/file.c:415
 exit_files+0x7e/0xa0 fs/file.c:435
 do_exit+0xc22/0x2ae0 kernel/exit.c:820
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x427/0x20f0 kernel/signal.c:2773
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Now io_uring_cancel_task_requests() can be called not through file
notes but directly, remove a WARN_ONCE() there that give us false
positives. That check is not very important and we catch it in other
places.

Fixes: 84965ff8a8 ("io_uring: if we see flush on exit, cancel related tasks")
Cc: stable@vger.kernel.org # 5.9+
Reported-by: syzbot+3e3d9bd0c6ce9efbc3ef@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:55:00 +01:00
Pavel Begunkov
8c7febfc91 io_uring: fix list corruption for splice file_get
[ Upstream commit f609cbb891 ]

kernel BUG at lib/list_debug.c:29!
Call Trace:
 __list_add include/linux/list.h:67 [inline]
 list_add include/linux/list.h:86 [inline]
 io_file_get+0x8cc/0xdb0 fs/io_uring.c:6466
 __io_splice_prep+0x1bc/0x530 fs/io_uring.c:3866
 io_splice_prep fs/io_uring.c:3920 [inline]
 io_req_prep+0x3546/0x4e80 fs/io_uring.c:6081
 io_queue_sqe+0x609/0x10d0 fs/io_uring.c:6628
 io_submit_sqe fs/io_uring.c:6705 [inline]
 io_submit_sqes+0x1495/0x2720 fs/io_uring.c:6953
 __do_sys_io_uring_enter+0x107d/0x1f30 fs/io_uring.c:9353
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

io_file_get() may be called from splice, and so REQ_F_INFLIGHT may
already be set.

Fixes: 02a13674fa ("io_uring: account io_uring internal files as REQ_F_INFLIGHT")
Cc: stable@vger.kernel.org # 5.9+
Reported-by: syzbot+6879187cf57845801267@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:55:00 +01:00
Hao Xu
7250f333ce io_uring: fix flush cqring overflow list while TASK_INTERRUPTIBLE
[ Upstream commit 6195ba0982 ]

Abaci reported the follow warning:

[   27.073425] do not call blocking ops when !TASK_RUNNING; state=1 set at [] prepare_to_wait_exclusive+0x3a/0xc0
[   27.075805] WARNING: CPU: 0 PID: 951 at kernel/sched/core.c:7853 __might_sleep+0x80/0xa0
[   27.077604] Modules linked in:
[   27.078379] CPU: 0 PID: 951 Comm: a.out Not tainted 5.11.0-rc3+ #1
[   27.079637] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[   27.080852] RIP: 0010:__might_sleep+0x80/0xa0
[   27.081835] Code: 65 48 8b 04 25 80 71 01 00 48 8b 90 c0 15 00 00 48 8b 70 18 48 c7 c7 08 39 95 82 c6 05 f9 5f de 08 01 48 89 d1 e8 00 c6 fa ff  0b eb bf 41 0f b6 f5 48 c7 c7 40 23 c9 82 e8 f3 48 ec 00 eb a7
[   27.084521] RSP: 0018:ffffc90000fe3ce8 EFLAGS: 00010286
[   27.085350] RAX: 0000000000000000 RBX: ffffffff82956083 RCX: 0000000000000000
[   27.086348] RDX: ffff8881057a0000 RSI: ffffffff8118cc9e RDI: ffff88813bc28570
[   27.087598] RBP: 00000000000003a7 R08: 0000000000000001 R09: 0000000000000001
[   27.088819] R10: ffffc90000fe3e00 R11: 00000000fffef9f0 R12: 0000000000000000
[   27.089819] R13: 0000000000000000 R14: ffff88810576eb80 R15: ffff88810576e800
[   27.091058] FS:  00007f7b144cf740(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
[   27.092775] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   27.093796] CR2: 00000000022da7b8 CR3: 000000010b928002 CR4: 00000000003706f0
[   27.094778] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   27.095780] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   27.097011] Call Trace:
[   27.097685]  __mutex_lock+0x5d/0xa30
[   27.098565]  ? prepare_to_wait_exclusive+0x71/0xc0
[   27.099412]  ? io_cqring_overflow_flush.part.101+0x6d/0x70
[   27.100441]  ? lockdep_hardirqs_on_prepare+0xe9/0x1c0
[   27.101537]  ? _raw_spin_unlock_irqrestore+0x2d/0x40
[   27.102656]  ? trace_hardirqs_on+0x46/0x110
[   27.103459]  ? io_cqring_overflow_flush.part.101+0x6d/0x70
[   27.104317]  io_cqring_overflow_flush.part.101+0x6d/0x70
[   27.105113]  io_cqring_wait+0x36e/0x4d0
[   27.105770]  ? find_held_lock+0x28/0xb0
[   27.106370]  ? io_uring_remove_task_files+0xa0/0xa0
[   27.107076]  __x64_sys_io_uring_enter+0x4fb/0x640
[   27.107801]  ? rcu_read_lock_sched_held+0x59/0xa0
[   27.108562]  ? lockdep_hardirqs_on_prepare+0xe9/0x1c0
[   27.109684]  ? syscall_enter_from_user_mode+0x26/0x70
[   27.110731]  do_syscall_64+0x2d/0x40
[   27.111296]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   27.112056] RIP: 0033:0x7f7b13dc8239
[   27.112663] Code: 01 00 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 00 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  3d 01 f0 ff ff 73 01 c3 48 8b 0d 27 ec 2c 00 f7 d8 64 89 01 48
[   27.115113] RSP: 002b:00007ffd6d7f5c88 EFLAGS: 00000286 ORIG_RAX: 00000000000001aa
[   27.116562] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7b13dc8239
[   27.117961] RDX: 000000000000478e RSI: 0000000000000000 RDI: 0000000000000003
[   27.118925] RBP: 00007ffd6d7f5cb0 R08: 0000000020000040 R09: 0000000000000008
[   27.119773] R10: 0000000000000001 R11: 0000000000000286 R12: 0000000000400480
[   27.120614] R13: 00007ffd6d7f5d90 R14: 0000000000000000 R15: 0000000000000000
[   27.121490] irq event stamp: 5635
[   27.121946] hardirqs last  enabled at (5643): [] console_unlock+0x5c4/0x740
[   27.123476] hardirqs last disabled at (5652): [] console_unlock+0x4e7/0x740
[   27.125192] softirqs last  enabled at (5272): [] __do_softirq+0x3c5/0x5aa
[   27.126430] softirqs last disabled at (5267): [] asm_call_irq_on_stack+0xf/0x20
[   27.127634] ---[ end trace 289d7e28fa60f928 ]---

This is caused by calling io_cqring_overflow_flush() which may sleep
after calling prepare_to_wait_exclusive() which set task state to
TASK_INTERRUPTIBLE

Reported-by: Abaci <abaci@linux.alibaba.com>
Fixes: 6c503150ae ("io_uring: patch up IOPOLL overflow_flush sync")
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:59 +01:00
Pavel Begunkov
d300d03a93 io_uring: fix cancellation taking mutex while TASK_UNINTERRUPTIBLE
[ Upstream commit ca70f00bed ]

do not call blocking ops when !TASK_RUNNING; state=2 set at
	[<00000000ced9dbfc>] prepare_to_wait+0x1f4/0x3b0
	kernel/sched/wait.c:262
WARNING: CPU: 1 PID: 19888 at kernel/sched/core.c:7853
	__might_sleep+0xed/0x100 kernel/sched/core.c:7848
RIP: 0010:__might_sleep+0xed/0x100 kernel/sched/core.c:7848
Call Trace:
 __mutex_lock_common+0xc4/0x2ef0 kernel/locking/mutex.c:935
 __mutex_lock kernel/locking/mutex.c:1103 [inline]
 mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1118
 io_wq_submit_work+0x39a/0x720 fs/io_uring.c:6411
 io_run_cancel fs/io-wq.c:856 [inline]
 io_wqe_cancel_pending_work fs/io-wq.c:990 [inline]
 io_wq_cancel_cb+0x614/0xcb0 fs/io-wq.c:1027
 io_uring_cancel_files fs/io_uring.c:8874 [inline]
 io_uring_cancel_task_requests fs/io_uring.c:8952 [inline]
 __io_uring_files_cancel+0x115d/0x19e0 fs/io_uring.c:9038
 io_uring_files_cancel include/linux/io_uring.h:51 [inline]
 do_exit+0x2e6/0x2490 kernel/exit.c:780
 do_group_exit+0x168/0x2d0 kernel/exit.c:922
 get_signal+0x16b5/0x2030 kernel/signal.c:2770
 arch_do_signal_or_restart+0x8e/0x6a0 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0xac/0x1e0 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x48/0x190 kernel/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Rewrite io_uring_cancel_files() to mimic __io_uring_task_cancel()'s
counting scheme, so it does all the heavy work before setting
TASK_UNINTERRUPTIBLE.

Cc: stable@vger.kernel.org # 5.9+
Reported-by: syzbot+f655445043a26a7cfab8@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
[axboe: fix inverted task check]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:59 +01:00
Pavel Begunkov
52382df81d io_uring: replace inflight_wait with tctx->wait
[ Upstream commit c98de08c99 ]

As tasks now cancel only theirs requests, and inflight_wait is awaited
only in io_uring_cancel_files(), which should be called with ->in_idle
set, instead of keeping a separate inflight_wait use tctx->wait.

That will add some spurious wakeups but actually is safer from point of
not hanging the task.

e.g.
task1                   | IRQ
                        | *start* io_complete_rw_common(link)
                        |        link: req1 -> req2 -> req3(with files)
*cancel_files()         |
io_wq_cancel(), etc.    |
                        | put_req(link), adds to io-wq req2
schedule()              |

So, task1 will never try to cancel req2 or req3. If req2 is
long-standing (e.g. read(empty_pipe)), this may hang.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:58 +01:00
Pavel Begunkov
b462a7beab io_uring: fix __io_uring_files_cancel() with TASK_UNINTERRUPTIBLE
[ Upstream commit a1bb3cd589 ]

If the tctx inflight number haven't changed because of cancellation,
__io_uring_task_cancel() will continue leaving the task in
TASK_UNINTERRUPTIBLE state, that's not expected by
__io_uring_files_cancel(). Ensure we always call finish_wait() before
retrying.

Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:58 +01:00
Jens Axboe
f0ff1a95bf io_uring: if we see flush on exit, cancel related tasks
[ Upstream commit 84965ff8a8 ]

Ensure we match tasks that belong to a dead or dying task as well, as we
need to reap those in addition to those belonging to the exiting task.

Cc: stable@vger.kernel.org # 5.9+
Reported-by: Josef Grieb <josef.grieb@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:57 +01:00
Jens Axboe
d16692a34e io_uring: account io_uring internal files as REQ_F_INFLIGHT
[ Upstream commit 02a13674fa ]

We need to actively cancel anything that introduces a potential circular
loop, where io_uring holds a reference to itself. If the file in question
is an io_uring file, then add the request to the inflight list.

Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:57 +01:00
Pavel Begunkov
1e7eb063a0 io_uring: fix files cancellation
[ Upstream commit bee749b187 ]

io_uring_cancel_files()'s task check condition mistakenly got flipped.

1. There can't be a request in the inflight list without
IO_WQ_WORK_FILES, kill this check to keep the whole condition simpler.
2. Also, don't call the function for files==NULL to not do such a check,
all that staff is already handled well by its counter part,
__io_uring_cancel_task_requests().

With that just flip the task check.

Also, it iowq-cancels all request of current task there, don't forget to
set right ->files into struct io_task_cancel.

Fixes: c1973b38bf639 ("io_uring: cancel only requests of current task")
Reported-by: syzbot+c0d52d0b3c0c3ffb9525@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:56 +01:00
Pavel Begunkov
dbdcde4422 io_uring: always batch cancel in *cancel_files()
[ Upstream commit f6edbabb83 ]

Instead of iterating over each request and cancelling it individually in
io_uring_cancel_files(), try to cancel all matching requests and use
->inflight_list only to check if there anything left.

In many cases it should be faster, and we can reuse a lot of code from
task cancellation.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:56 +01:00
Pavel Begunkov
f8fbdbb607 io_uring: pass files into kill timeouts/poll
[ Upstream commit 6b81928d4c ]

Make io_poll_remove_all() and io_kill_timeouts() to match against files
as well. A preparation patch, effectively not used by now.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:55 +01:00
Pavel Begunkov
49250f33bb io_uring: don't iterate io_uring_cancel_files()
[ Upstream commit b52fda00dd ]

io_uring_cancel_files() guarantees to cancel all matching requests,
that's not necessary to do that in a loop. Move it up in the callchain
into io_uring_cancel_task_requests().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:55 +01:00
Pavel Begunkov
f6d93f8555 io_uring: add a {task,files} pair matching helper
[ Upstream commit 08d2363464 ]

Add io_match_task() that matches both task and files.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:54 +01:00
Pavel Begunkov
fe9334186a io_uring: simplify io_task_match()
[ Upstream commit 06de5f5973 ]

If IORING_SETUP_SQPOLL is set all requests belong to the corresponding
SQPOLL task, so skip task checking in that case and always match.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13 13:54:54 +01:00
Muchun Song
afe6c31b84 mm: hugetlbfs: fix cannot migrate the fallocated HugeTLB page
commit 585fc0d287 upstream.

If a new hugetlb page is allocated during fallocate it will not be
marked as active (set_page_huge_active) which will result in a later
isolate_huge_page failure when the page migration code would like to
move that page.  Such a failure would be unexpected and wrong.

Only export set_page_huge_active, just leave clear_page_huge_active as
static.  Because there are no external users.

Link: https://lkml.kernel.org/r/20210115124942.46403-3-songmuchun@bytedance.com
Fixes: 70c3547e36 (hugetlbfs: add hugetlbfs_fallocate())
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10 09:29:20 +01:00
Xiaoguang Wang
4f25d448d9 io_uring: don't modify identity's files uncess identity is cowed
commit d7e10d4769 upstream.

Abaci Robot reported following panic:
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 800000010ef3f067 P4D 800000010ef3f067 PUD 10d9df067 PMD 0
Oops: 0002 [#1] SMP PTI
CPU: 0 PID: 1869 Comm: io_wqe_worker-0 Not tainted 5.11.0-rc3+ #1
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
RIP: 0010:put_files_struct+0x1b/0x120
Code: 24 18 c7 00 f4 ff ff ff e9 4d fd ff ff 66 90 0f 1f 44 00 00 41 57 41 56 49 89 fe 41 55 41 54 55 53 48 83 ec 08 e8 b5 6b db ff  41 ff 0e 74 13 48 83 c4 08 5b 5d 41 5c 41 5d 41 5e 41 5f e9 9c
RSP: 0000:ffffc90002147d48 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88810d9a5300 RCX: 0000000000000000
RDX: ffff88810d87c280 RSI: ffffffff8144ba6b RDI: 0000000000000000
RBP: 0000000000000080 R08: 0000000000000001 R09: ffffffff81431500
R10: ffff8881001be000 R11: 0000000000000000 R12: ffff88810ac2f800
R13: ffff88810af38a00 R14: 0000000000000000 R15: ffff8881057130c0
FS:  0000000000000000(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000010dbaa002 CR4: 00000000003706f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __io_clean_op+0x10c/0x2a0
 io_dismantle_req+0x3c7/0x600
 __io_free_req+0x34/0x280
 io_put_req+0x63/0xb0
 io_worker_handle_work+0x60e/0x830
 ? io_wqe_worker+0x135/0x520
 io_wqe_worker+0x158/0x520
 ? __kthread_parkme+0x96/0xc0
 ? io_worker_handle_work+0x830/0x830
 kthread+0x134/0x180
 ? kthread_create_worker_on_cpu+0x90/0x90
 ret_from_fork+0x1f/0x30
Modules linked in:
CR2: 0000000000000000
---[ end trace c358ca86af95b1e7 ]---

I guess case below can trigger above panic: there're two threads which
operates different io_uring ctxs and share same sqthread identity, and
later one thread exits, io_uring_cancel_task_requests() will clear
task->io_uring->identity->files to be NULL in sqpoll mode, then another
ctx that uses same identity will panic.

Indeed we don't need to clear task->io_uring->identity->files here,
io_grab_identity() should handle identity->files changes well, if
task->io_uring->identity->files is not equal to current->files,
io_cow_identity() should handle this changes well.

Cc: stable@vger.kernel.org # 5.5+
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10 09:29:19 +01:00
Pavel Shilovsky
2502610927 smb3: fix crediting for compounding when only one request in flight
commit 91792bb808 upstream.

Currently we try to guess if a compound request is going to
succeed waiting for credits or not based on the number of
requests in flight. This approach doesn't work correctly
all the time because there may be only one request in
flight which is going to bring multiple credits satisfying
the compound request.

Change the behavior to fail a request only if there are no requests
in flight at all and proceed waiting for credits otherwise.

Cc: <stable@vger.kernel.org> # 5.1+
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10 09:29:18 +01:00
Gustavo A. R. Silva
b793e9fca6 smb3: Fix out-of-bounds bug in SMB2_negotiate()
commit 8d8d1dbefc upstream.

While addressing some warnings generated by -Warray-bounds, I found this
bug that was introduced back in 2017:

  CC [M]  fs/cifs/smb2pdu.o
fs/cifs/smb2pdu.c: In function ‘SMB2_negotiate’:
fs/cifs/smb2pdu.c:822:16: warning: array subscript 1 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
  822 |   req->Dialects[1] = cpu_to_le16(SMB30_PROT_ID);
      |   ~~~~~~~~~~~~~^~~
fs/cifs/smb2pdu.c:823:16: warning: array subscript 2 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
  823 |   req->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
      |   ~~~~~~~~~~~~~^~~
fs/cifs/smb2pdu.c:824:16: warning: array subscript 3 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
  824 |   req->Dialects[3] = cpu_to_le16(SMB311_PROT_ID);
      |   ~~~~~~~~~~~~~^~~
fs/cifs/smb2pdu.c:816:16: warning: array subscript 1 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
  816 |   req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
      |   ~~~~~~~~~~~~~^~~

At the time, the size of array _Dialects_ was changed from 1 to 3 in struct
validate_negotiate_info_req, and then in 2019 it was changed from 3 to 4,
but those changes were never made in struct smb2_negotiate_req, which has
led to a 3 and a half years old out-of-bounds bug in function
SMB2_negotiate() (fs/cifs/smb2pdu.c).

Fix this by increasing the size of array _Dialects_ in struct
smb2_negotiate_req to 4.

Fixes: 9764c02fcb ("SMB3: Add support for multidialect negotiate (SMB2.1 and later)")
Fixes: d5c7076b77 ("smb3: add smb3.1.1 to default dialect list")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10 09:29:17 +01:00
Aurelien Aptel
7a3361e5ec cifs: report error instead of invalid when revalidating a dentry fails
commit 21b200d091 upstream.

Assuming
- //HOST/a is mounted on /mnt
- //HOST/b is mounted on /mnt/b

On a slow connection, running 'df' and killing it while it's
processing /mnt/b can make cifs_get_inode_info() returns -ERESTARTSYS.

This triggers the following chain of events:
=> the dentry revalidation fail
=> dentry is put and released
=> superblock associated with the dentry is put
=> /mnt/b is unmounted

This patch makes cifs_d_revalidate() return the error instead of 0
(invalid) when cifs_revalidate_dentry() fails, except for ENOENT (file
deleted) and ESTALE (file recreated).

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Suggested-by: Shyam Prasad N <nspmangalore@gmail.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
CC: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10 09:29:17 +01:00
Sargun Dhillon
8ccf963c62 ovl: implement volatile-specific fsync error behaviour
commit 335d3fc579 upstream.

Overlayfs's volatile option allows the user to bypass all forced sync calls
to the upperdir filesystem. This comes at the cost of safety. We can never
ensure that the user's data is intact, but we can make a best effort to
expose whether or not the data is likely to be in a bad state.

The best way to handle this in the time being is that if an overlayfs's
upperdir experiences an error after a volatile mount occurs, that error
will be returned on fsync, fdatasync, sync, and syncfs. This is
contradictory to the traditional behaviour of VFS which fails the call
once, and only raises an error if a subsequent fsync error has occurred,
and been raised by the filesystem.

One awkward aspect of the patch is that we have to manually set the
superblock's errseq_t after the sync_fs callback as opposed to just
returning an error from syncfs. This is because the call chain looks
something like this:

sys_syncfs ->
	sync_filesystem ->
		__sync_filesystem ->
			/* The return value is ignored here
			sb->s_op->sync_fs(sb)
			_sync_blockdev
		/* Where the VFS fetches the error to raise to userspace */
		errseq_check_and_advance

Because of this we call errseq_set every time the sync_fs callback occurs.
Due to the nature of this seen / unseen dichotomy, if the upperdir is an
inconsistent state at the initial mount time, overlayfs will refuse to
mount, as overlayfs cannot get a snapshot of the upperdir's errseq that
will increment on error until the user calls syncfs.

Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Suggested-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Fixes: c86243b090 ("ovl: provide a mount option "volatile"")
Cc: stable@vger.kernel.org
Reviewed-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10 09:29:16 +01:00
Miklos Szeredi
a66f82a1de ovl: avoid deadlock on directory ioctl
commit b854cc659d upstream.

The function ovl_dir_real_file() currently uses the inode lock to serialize
writes to the od->upperfile field.

However, this function will get called by ovl_ioctl_set_flags(), which
utilizes the inode lock too.  In this case ovl_dir_real_file() will try to
claim a lock that is owned by a function in its call stack, which won't get
released before ovl_dir_real_file() returns.

Fix by replacing the open coded compare and exchange by an explicit atomic
op.

Fixes: 61536bed21 ("ovl: support [S|G]ETFLAGS and FS[S|G]ETXATTR ioctls for directories")
Cc: stable@vger.kernel.org # v5.10
Reported-by: Icenowy Zheng <icenowy@aosc.io>
Tested-by: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10 09:29:15 +01:00
Liangyan
fb8caef7c0 ovl: fix dentry leak in ovl_get_redirect
commit e04527fefb upstream.

We need to lock d_parent->d_lock before dget_dlock, or this may
have d_lockref updated parallelly like calltrace below which will
cause dentry->d_lockref leak and risk a crash.

     CPU 0                                CPU 1
ovl_set_redirect                       lookup_fast
  ovl_get_redirect                       __d_lookup
    dget_dlock
      //no lock protection here            spin_lock(&dentry->d_lock)
      dentry->d_lockref.count++            dentry->d_lockref.count++

[   49.799059] PGD 800000061fed7067 P4D 800000061fed7067 PUD 61fec5067 PMD 0
[   49.799689] Oops: 0002 [#1] SMP PTI
[   49.800019] CPU: 2 PID: 2332 Comm: node Not tainted 4.19.24-7.20.al7.x86_64 #1
[   49.800678] Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 8a46cfe 04/01/2014
[   49.801380] RIP: 0010:_raw_spin_lock+0xc/0x20
[   49.803470] RSP: 0018:ffffac6fc5417e98 EFLAGS: 00010246
[   49.803949] RAX: 0000000000000000 RBX: ffff93b8da3446c0 RCX: 0000000a00000000
[   49.804600] RDX: 0000000000000001 RSI: 000000000000000a RDI: 0000000000000088
[   49.805252] RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff993cf040
[   49.805898] R10: ffff93b92292e580 R11: ffffd27f188a4b80 R12: 0000000000000000
[   49.806548] R13: 00000000ffffff9c R14: 00000000fffffffe R15: ffff93b8da3446c0
[   49.807200] FS:  00007ffbedffb700(0000) GS:ffff93b927880000(0000) knlGS:0000000000000000
[   49.807935] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   49.808461] CR2: 0000000000000088 CR3: 00000005e3f74006 CR4: 00000000003606a0
[   49.809113] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   49.809758] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   49.810410] Call Trace:
[   49.810653]  d_delete+0x2c/0xb0
[   49.810951]  vfs_rmdir+0xfd/0x120
[   49.811264]  do_rmdir+0x14f/0x1a0
[   49.811573]  do_syscall_64+0x5b/0x190
[   49.811917]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   49.812385] RIP: 0033:0x7ffbf505ffd7
[   49.814404] RSP: 002b:00007ffbedffada8 EFLAGS: 00000297 ORIG_RAX: 0000000000000054
[   49.815098] RAX: ffffffffffffffda RBX: 00007ffbedffb640 RCX: 00007ffbf505ffd7
[   49.815744] RDX: 0000000004449700 RSI: 0000000000000000 RDI: 0000000006c8cd50
[   49.816394] RBP: 00007ffbedffaea0 R08: 0000000000000000 R09: 0000000000017d0b
[   49.817038] R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000012
[   49.817687] R13: 00000000072823d8 R14: 00007ffbedffb700 R15: 00000000072823d8
[   49.818338] Modules linked in: pvpanic cirrusfb button qemu_fw_cfg atkbd libps2 i8042
[   49.819052] CR2: 0000000000000088
[   49.819368] ---[ end trace 4e652b8aa299aa2d ]---
[   49.819796] RIP: 0010:_raw_spin_lock+0xc/0x20
[   49.821880] RSP: 0018:ffffac6fc5417e98 EFLAGS: 00010246
[   49.822363] RAX: 0000000000000000 RBX: ffff93b8da3446c0 RCX: 0000000a00000000
[   49.823008] RDX: 0000000000000001 RSI: 000000000000000a RDI: 0000000000000088
[   49.823658] RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff993cf040
[   49.825404] R10: ffff93b92292e580 R11: ffffd27f188a4b80 R12: 0000000000000000
[   49.827147] R13: 00000000ffffff9c R14: 00000000fffffffe R15: ffff93b8da3446c0
[   49.828890] FS:  00007ffbedffb700(0000) GS:ffff93b927880000(0000) knlGS:0000000000000000
[   49.830725] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   49.832359] CR2: 0000000000000088 CR3: 00000005e3f74006 CR4: 00000000003606a0
[   49.834085] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   49.835792] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Cc: <stable@vger.kernel.org>
Fixes: a6c6065511 ("ovl: redirect on rename-dir")
Signed-off-by: Liangyan <liangyan.peng@linux.alibaba.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10 09:29:15 +01:00
David Howells
e5ed4e08d8 rxrpc: Fix deadlock around release of dst cached on udp tunnel
[ Upstream commit 5399d52233 ]

AF_RXRPC sockets use UDP ports in encap mode.  This causes socket and dst
from an incoming packet to get stolen and attached to the UDP socket from
whence it is leaked when that socket is closed.

When a network namespace is removed, the wait for dst records to be cleaned
up happens before the cleanup of the rxrpc and UDP socket, meaning that the
wait never finishes.

Fix this by moving the rxrpc (and, by dependence, the afs) private
per-network namespace registrations to the device group rather than subsys
group.  This allows cached rxrpc local endpoints to be cleared and their
UDP sockets closed before we try waiting for the dst records.

The symptom is that lines looking like the following:

	unregister_netdevice: waiting for lo to become free

get emitted at regular intervals after running something like the
referenced syzbot test.

Thanks to Vadim for tracking this down and work out the fix.

Reported-by: syzbot+df400f2f24a1677cd7e0@syzkaller.appspotmail.com
Reported-by: Vadim Fedorenko <vfedorenko@novek.ru>
Fixes: 5271953cad ("rxrpc: Use the UDP encap_rcv hook")
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vadim Fedorenko <vfedorenko@novek.ru>
Link: https://lore.kernel.org/r/161196443016.3868642.5577440140646403533.stgit@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-10 09:29:13 +01:00
lianzhi chang
a9fd4ef6e5 udf: fix the problem that the disc content is not displayed
[ Upstream commit 5cdc4a6950 ]

When the capacity of the disc is too large (assuming the 4.7G
specification), the disc (UDF file system) will be burned
multiple times in the windows (Multisession Usage). When the
remaining capacity of the CD is less than 300M (estimated
value, for reference only), open the CD in the Linux system,
the content of the CD is displayed as blank (the kernel will
say "No VRS found"). Windows can display the contents of the
CD normally.
Through analysis, in the "fs/udf/super.c": udf_check_vsd
function, the actual value of VSD_MAX_SECTOR_OFFSET may
be much larger than 0x800000. According to the current code
logic, it is found that the type of sbi->s_session is "__s32",
 when the remaining capacity of the disc is less than 300M
(take a set of test values: sector=3154903040,
sbi->s_session=1540464, sb->s_blocksize_bits=11 ), the
calculation result of "sbi->s_session << sb->s_blocksize_bits"
 will overflow. Therefore, it is necessary to convert the
type of s_session to "loff_t" (when udf_check_vsd starts,
assign a value to _sector, which is also converted in this
way), so that the result will not overflow, and then the
content of the disc can be displayed normally.

Link: https://lore.kernel.org/r/20210114075741.30448-1-changlianzhi@uniontech.com
Signed-off-by: lianzhi chang <changlianzhi@uniontech.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-07 15:37:15 +01:00
Trond Myklebust
d46c0d64db pNFS/NFSv4: Update the layout barrier when we schedule a layoutreturn
[ Upstream commit 1bcf34fdac ]

When we're scheduling a layoutreturn, we need to ignore any further
incoming layouts with sequence ids that are going to be affected by the
layout return.

Fixes: 44ea8dfce0 ("NFS/pnfs: Reference the layout cred in pnfs_prepare_layoutreturn()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-03 23:28:47 +01:00
Trond Myklebust
dba0d4b150 pNFS/NFSv4: Fix a layout segment leak in pnfs_layout_process()
[ Upstream commit 814b849713 ]

If the server returns a new stateid that does not match the one in our
cache, then pnfs_layout_process() will leak the layout segments returned
by pnfs_mark_layout_stateid_invalid().

Fixes: 9888d837f3 ("pNFS: Force a retry of LAYOUTGET if the stateid doesn't match our cache")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-03 23:28:47 +01:00
Maxim Mikityanskiy
f39005edf5 Revert "block: simplify set_init_blocksize" to regain lost performance
commit 8dc932d3e8 upstream.

The cited commit introduced a serious regression with SATA write speed,
as found by bisecting. This patch reverts this commit, which restores
write speed back to the values observed before this commit.

The performance tests were done on a Helios4 NAS (2nd batch) with 4 HDDs
(WD8003FFBX) using dd (bs=1M count=2000). "Direct" is a test with a
single HDD, the rest are different RAID levels built over the first
partitions of 4 HDDs. Test results are in MB/s, R is read, W is write.

                | Direct | RAID0 | RAID10 f2 | RAID10 n2 | RAID6
----------------+--------+-------+-----------+-----------+--------
9011495c94    | R:256  | R:313 | R:276     | R:313     | R:323
(before faulty) | W:254  | W:253 | W:195     | W:204     | W:117
----------------+--------+-------+-----------+-----------+--------
5ff9f19231    | R:257  | R:398 | R:312     | R:344     | R:391
(faulty commit) | W:154  | W:122 | W:67.7    | W:66.6    | W:67.2
----------------+--------+-------+-----------+-----------+--------
5.10.10         | R:256  | R:401 | R:312     | R:356     | R:375
unpatched       | W:149  | W:123 | W:64      | W:64.1    | W:61.5
----------------+--------+-------+-----------+-----------+--------
5.10.10         | R:255  | R:396 | R:312     | R:340     | R:393
patched         | W:247  | W:274 | W:220     | W:225     | W:121

Applying this patch doesn't hurt read performance, while improves the
write speed by 1.5x - 3.5x (more impact on RAID tests). The write speed
is restored back to the state before the faulty commit, and even a bit
higher in RAID tests (which aren't HDD-bound on this device) - that is
likely related to other optimizations done between the faulty commit and
5.10.10 which also improved the read speed.

Signed-off-by: Maxim Mikityanskiy <maxtram95@gmail.com>
Fixes: 5ff9f19231 ("block: simplify set_init_blocksize")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-03 23:28:45 +01:00
Pavel Begunkov
bc79ff0b1a io_uring: fix wqe->lock/completion_lock deadlock
commit 907d1df30a upstream.

Joseph reports following deadlock:

CPU0:
...
io_kill_linked_timeout  // &ctx->completion_lock
io_commit_cqring
__io_queue_deferred
__io_queue_async_work
io_wq_enqueue
io_wqe_enqueue  // &wqe->lock

CPU1:
...
__io_uring_files_cancel
io_wq_cancel_cb
io_wqe_cancel_pending_work  // &wqe->lock
io_cancel_task_cb  // &ctx->completion_lock

Only __io_queue_deferred() calls queue_async_work() while holding
ctx->completion_lock, enqueue drained requests via io_req_task_queue()
instead.

Cc: stable@vger.kernel.org # 5.9+
Reported-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-03 23:28:41 +01:00
Josef Bacik
2175bf57dc btrfs: fix possible free space tree corruption with online conversion
commit 2f96e40212 upstream.

While running btrfs/011 in a loop I would often ASSERT() while trying to
add a new free space entry that already existed, or get an EEXIST while
adding a new block to the extent tree, which is another indication of
double allocation.

This occurs because when we do the free space tree population, we create
the new root and then populate the tree and commit the transaction.
The problem is when you create a new root, the root node and commit root
node are the same.  During this initial transaction commit we will run
all of the delayed refs that were paused during the free space tree
generation, and thus begin to cache block groups.  While caching block
groups the caching thread will be reading from the main root for the
free space tree, so as we make allocations we'll be changing the free
space tree, which can cause us to add the same range twice which results
in either the ASSERT(ret != -EEXIST); in __btrfs_add_free_space, or in a
variety of different errors when running delayed refs because of a
double allocation.

Fix this by marking the fs_info as unsafe to load the free space tree,
and fall back on the old slow method.  We could be smarter than this,
for example caching the block group while we're populating the free
space tree, but since this is a serious problem I've opted for the
simplest solution.

CC: stable@vger.kernel.org # 4.9+
Fixes: a5ed918285 ("Btrfs: implement the free space B-tree")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-03 23:28:40 +01:00
Su Yue
f343bf1aaf btrfs: fix lockdep warning due to seqcount_mutex on 32bit arch
commit c41ec4529d upstream.

This effectively reverts commit d5c8238849 ("btrfs: convert
data_seqcount to seqcount_mutex_t").

While running fstests on 32 bits test box, many tests failed because of
warnings in dmesg. One of those warnings (btrfs/003):

  [66.441317] WARNING: CPU: 6 PID: 9251 at include/linux/seqlock.h:279 btrfs_remove_chunk+0x58b/0x7b0 [btrfs]
  [66.441446] CPU: 6 PID: 9251 Comm: btrfs Tainted: G           O      5.11.0-rc4-custom+ #5
  [66.441449] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ArchLinux 1.14.0-1 04/01/2014
  [66.441451] EIP: btrfs_remove_chunk+0x58b/0x7b0 [btrfs]
  [66.441472] EAX: 00000000 EBX: 00000001 ECX: c576070c EDX: c6b15803
  [66.441475] ESI: 10000000 EDI: 00000000 EBP: c56fbcfc ESP: c56fbc70
  [66.441477] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010246
  [66.441481] CR0: 80050033 CR2: 05c8da20 CR3: 04b20000 CR4: 00350ed0
  [66.441485] Call Trace:
  [66.441510]  btrfs_relocate_chunk+0xb1/0x100 [btrfs]
  [66.441529]  ? btrfs_lookup_block_group+0x17/0x20 [btrfs]
  [66.441562]  btrfs_balance+0x8ed/0x13b0 [btrfs]
  [66.441586]  ? btrfs_ioctl_balance+0x333/0x3c0 [btrfs]
  [66.441619]  ? __this_cpu_preempt_check+0xf/0x11
  [66.441643]  btrfs_ioctl_balance+0x333/0x3c0 [btrfs]
  [66.441664]  ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs]
  [66.441683]  btrfs_ioctl+0x414/0x2ae0 [btrfs]
  [66.441700]  ? __lock_acquire+0x35f/0x2650
  [66.441717]  ? lockdep_hardirqs_on+0x87/0x120
  [66.441720]  ? lockdep_hardirqs_on_prepare+0xd0/0x1e0
  [66.441724]  ? call_rcu+0x2d3/0x530
  [66.441731]  ? __might_fault+0x41/0x90
  [66.441736]  ? kvm_sched_clock_read+0x15/0x50
  [66.441740]  ? sched_clock+0x8/0x10
  [66.441745]  ? sched_clock_cpu+0x13/0x180
  [66.441750]  ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs]
  [66.441750]  ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs]
  [66.441768]  __ia32_sys_ioctl+0x165/0x8a0
  [66.441773]  ? __this_cpu_preempt_check+0xf/0x11
  [66.441785]  ? __might_fault+0x89/0x90
  [66.441791]  __do_fast_syscall_32+0x54/0x80
  [66.441796]  do_fast_syscall_32+0x32/0x70
  [66.441801]  do_SYSENTER_32+0x15/0x20
  [66.441805]  entry_SYSENTER_32+0x9f/0xf2
  [66.441808] EIP: 0xab7b5549
  [66.441814] EAX: ffffffda EBX: 00000003 ECX: c4009420 EDX: bfa91f5c
  [66.441816] ESI: 00000003 EDI: 00000001 EBP: 00000000 ESP: bfa91e98
  [66.441818] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00000292
  [66.441833] irq event stamp: 42579
  [66.441835] hardirqs last  enabled at (42585): [<c60eb065>] console_unlock+0x495/0x590
  [66.441838] hardirqs last disabled at (42590): [<c60eafd5>] console_unlock+0x405/0x590
  [66.441840] softirqs last  enabled at (41698): [<c601b76c>] call_on_stack+0x1c/0x60
  [66.441843] softirqs last disabled at (41681): [<c601b76c>] call_on_stack+0x1c/0x60

  ========================================================================
  btrfs_remove_chunk+0x58b/0x7b0:
  __seqprop_mutex_assert at linux/./include/linux/seqlock.h:279
  (inlined by) btrfs_device_set_bytes_used at linux/fs/btrfs/volumes.h:212
  (inlined by) btrfs_remove_chunk at linux/fs/btrfs/volumes.c:2994
  ========================================================================

The warning is produced by lockdep_assert_held() in
__seqprop_mutex_assert() if CONFIG_LOCKDEP is enabled.
And "olumes.c:2994 is btrfs_device_set_bytes_used() with mutex lock
fs_info->chunk_mutex held already.

After adding some debug prints, the cause was found that many
__alloc_device() are called with NULL @fs_info (during scanning ioctl).
Inside the function, btrfs_device_data_ordered_init() is expanded to
seqcount_mutex_init().  In this scenario, its second
parameter info->chunk_mutex  is &NULL->chunk_mutex which equals
to offsetof(struct btrfs_fs_info, chunk_mutex) unexpectedly. Thus,
seqcount_mutex_init() is called in wrong way. And later
btrfs_device_get/set helpers trigger lockdep warnings.

The device and filesystem object lifetimes are different and we'd have
to synchronize initialization of the btrfs_device::data_seqcount with
the fs_info, possibly using some additional synchronization. It would
still not prevent concurrent access to the seqcount lock when it's used
for read and initialization.

Commit d5c8238849 ("btrfs: convert data_seqcount to seqcount_mutex_t")
does not mention a particular problem being fixed so revert should not
cause any harm and we'll get the lockdep warning fixed.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=210139
Reported-by: Erhard F <erhard_f@mailbox.org>
Fixes: d5c8238849 ("btrfs: convert data_seqcount to seqcount_mutex_t")
CC: stable@vger.kernel.org # 5.10
CC: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Su Yue <l@damenly.su>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-03 23:28:40 +01:00
Pavel Begunkov
d92d00861e io_uring: fix sleeping under spin in __io_clean_op
[ Upstream commit 9d5c819068 ]

[   27.629441] BUG: sleeping function called from invalid context
	at fs/file.c:402
[   27.631317] in_atomic(): 1, irqs_disabled(): 1, non_block: 0,
	pid: 1012, name: io_wqe_worker-0
[   27.633220] 1 lock held by io_wqe_worker-0/1012:
[   27.634286]  #0: ffff888105e26c98 (&ctx->completion_lock)
	{....}-{2:2}, at: __io_req_complete.part.102+0x30/0x70
[   27.649249] Call Trace:
[   27.649874]  dump_stack+0xac/0xe3
[   27.650666]  ___might_sleep+0x284/0x2c0
[   27.651566]  put_files_struct+0xb8/0x120
[   27.652481]  __io_clean_op+0x10c/0x2a0
[   27.653362]  __io_cqring_fill_event+0x2c1/0x350
[   27.654399]  __io_req_complete.part.102+0x41/0x70
[   27.655464]  io_openat2+0x151/0x300
[   27.656297]  io_issue_sqe+0x6c/0x14e0
[   27.660991]  io_wq_submit_work+0x7f/0x240
[   27.662890]  io_worker_handle_work+0x501/0x8a0
[   27.664836]  io_wqe_worker+0x158/0x520
[   27.667726]  kthread+0x134/0x180
[   27.669641]  ret_from_fork+0x1f/0x30

Instead of cleaning files on overflow, return back overflow cancellation
into io_uring_cancel_files(). Previously it was racy to clean
REQ_F_OVERFLOW flag, but we got rid of it, and can do it through
repetitive attempts targeting all matching requests.

Cc: stable@vger.kernel.org # 5.9+
Reported-by: Abaci <abaci@linux.alibaba.com>
Reported-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30 13:55:19 +01:00
Pavel Begunkov
7bccd1c191 io_uring: dont kill fasync under completion_lock
[ Upstream commit 4aa84f2ffa ]

      CPU0                    CPU1
       ----                    ----
  lock(&new->fa_lock);
                               local_irq_disable();
                               lock(&ctx->completion_lock);
                               lock(&new->fa_lock);
  <Interrupt>
    lock(&ctx->completion_lock);

 *** DEADLOCK ***

Move kill_fasync() out of io_commit_cqring() to io_cqring_ev_posted(),
so it doesn't hold completion_lock while doing it. That saves from the
reported deadlock, and it's just nice to shorten the locking time and
untangle nested locks (compl_lock -> wq_head::lock).

Cc: stable@vger.kernel.org # 5.5+
Reported-by: syzbot+91ca3f25bd7f795f019c@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30 13:55:19 +01:00
Pavel Begunkov
186725a80c io_uring: fix skipping disabling sqo on exec
[ Upstream commit 0b5cd6c32b ]

If there are no requests at the time __io_uring_task_cancel() is called,
tctx_inflight() returns zero and and it terminates not getting a chance
to go through __io_uring_files_cancel() and do
io_disable_sqo_submit(). And we absolutely want them disabled by the
time cancellation ends.

Cc: stable@vger.kernel.org # 5.5+
Reported-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Fixes: d9d05217cb ("io_uring: stop SQPOLL submit on creator's death")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30 13:55:19 +01:00
Pavel Begunkov
54b4c4f9ab io_uring: fix uring_flush in exit_files() warning
[ Upstream commit 4325cb498c ]

WARNING: CPU: 1 PID: 11100 at fs/io_uring.c:9096
	io_uring_flush+0x326/0x3a0 fs/io_uring.c:9096
RIP: 0010:io_uring_flush+0x326/0x3a0 fs/io_uring.c:9096
Call Trace:
 filp_close+0xb4/0x170 fs/open.c:1280
 close_files fs/file.c:401 [inline]
 put_files_struct fs/file.c:416 [inline]
 put_files_struct+0x1cc/0x350 fs/file.c:413
 exit_files+0x7e/0xa0 fs/file.c:433
 do_exit+0xc22/0x2ae0 kernel/exit.c:820
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x3e9/0x20a0 kernel/signal.c:2770
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

An SQPOLL ring creator task may have gotten rid of its file note during
exit and called io_disable_sqo_submit(), but the io_uring is still left
referenced through fdtable, which will be put during close_files() and
cause a false positive warning.

First split the warning into two for more clarity when is hit, and the
add sqo_dead check to handle the described case.

Cc: stable@vger.kernel.org # 5.5+
Reported-by: syzbot+a32b546d58dde07875a1@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30 13:55:19 +01:00