[ Upstream commit 58bc6d1be2f3b0ceecb6027dfa17513ec6aa2abb ]
When parsing the ExtendedAttr data, malicous or corrupt attribute length
could cause kernel hangs and buffer overruns in some special cases.
Link: https://lore.kernel.org/r/20210822093332.25234-1-stian.skjelstad@gmail.com
Signed-off-by: Stian Skjelstad <stian.skjelstad@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2f488f698fda820f8e6fa0407630154eceb145d6 ]
There is an existing lock hierarchy of
&dev->event_lock --> &fasync_struct.fa_lock --> &f->f_owner.lock
from the following call chain:
input_inject_event():
spin_lock_irqsave(&dev->event_lock,...);
input_handle_event():
input_pass_values():
input_to_handler():
evdev_events():
evdev_pass_values():
spin_lock(&client->buffer_lock);
__pass_event():
kill_fasync():
kill_fasync_rcu():
read_lock(&fa->fa_lock);
send_sigio():
read_lock_irqsave(&fown->lock,...);
&dev->event_lock is HARDIRQ-safe, so interrupts have to be disabled
while grabbing &fasync_struct.fa_lock, otherwise we invert the lock
hierarchy. However, since kill_fasync which calls kill_fasync_rcu is
an exported symbol, it may not necessarily be called with interrupts
disabled.
As kill_fasync_rcu may be called with interrupts disabled (for
example, in the call chain above), we replace calls to
read_lock/read_unlock on &fasync_struct.fa_lock in kill_fasync_rcu
with read_lock_irqsave/read_unlock_irqrestore.
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 28ce50f8d96ec9035f60c9348294ea26b94db944 ]
Currently iocharset=utf8 mount option is broken. To use UTF-8 as iocharset,
it is required to use utf8 mount option.
Fix iocharset=utf8 mount option to use be equivalent to the utf8 mount
option.
If UTF-8 as iocharset is used then s_nls_iocharset is set to NULL. So
simplify code around, remove s_utf8 field as to distinguish between UTF-8
and non-UTF-8 it is needed just to check if s_nls_iocharset is set to NULL
or not.
Link: https://lore.kernel.org/r/20210808162453.1653-5-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 781d2a9a2fc7d0be53a072794dc03ef6de770f3d ]
We were checking validity of LVID entries only when getting
implementation use information from LVID in udf_sb_lvidiu(). However if
the LVID is suitably corrupted, it can cause problems also to code such
as udf_count_free() which doesn't use udf_sb_lvidiu(). So check validity
of LVID already when loading it from the disk and just disable LVID
altogether when it is not valid.
Reported-by: syzbot+7fbfe5fed73ebb675748@syzkaller.appspotmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 15db16837a35d8007cb8563358787412213db25e upstream.
Server responds to LOOKUP and other ops (READDIRPLUS/CREATE/MKNOD/...)
with ourarg containing nodeid and generation.
If a fuse inode is found in inode cache with the same nodeid but different
generation, the existing fuse inode should be unhashed and marked "bad" and
a new inode with the new generation should be hashed instead.
This can happen, for example, with passhrough fuse filesystem that returns
the real filesystem ino/generation on lookup and where real inode numbers
can get recycled due to real files being unlinked not via the fuse
passthrough filesystem.
With current code, this situation will not be detected and an old fuse
dentry that used to point to an older generation real inode, can be used to
access a completely new inode, which should be accessed only via the new
dentry.
Note that because the FORGET message carries the nodeid w/o generation, the
server should wait to get FORGET counts for the nlookup counts of the old
and reused inodes combined, before it can free the resources associated to
that nodeid.
Stable backport notes:
* This is not a regression. The bug has been in fuse forever, but only
a certain class of low level fuse filesystems can trigger this bug
* Because there is no way to check if this fix is applied in runtime,
libfuse test_examples.py tests this fix with hardcoded check for
kernel version >= 5.14
* After backport to stable kernel(s), the libfuse test can be updated
to also check minimal stable kernel version(s)
* Depends on "fuse: fix bad inode" which is already applied to stable
kernels v5.4.y and v5.10.y
* Required backporting helper inode_wrong_type()
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-fsdevel/CAOQ4uxi8DymG=JO_sAU+wS8akFdzh+PuXwW3Ebgahd2Nwnh7zA@mail.gmail.com/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6e3e2c4362e41a2f18e3f7a5ad81bd2f49a47b85 upstream.
inode_wrong_type(inode, mode) returns true if setting inode->i_mode
to given value would've changed the inode type. We have enough of
those checks open-coded to make a helper worthwhile.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 064c734986011390b4d111f1a99372b7f26c3850 upstream.
The stat() family of syscalls report the wrong size for encrypted
symlinks, which has caused breakage in several userspace programs.
Fix this by calling fscrypt_symlink_getattr() after ubifs_getattr() for
encrypted symlinks. This function computes the correct size by reading
and decrypting the symlink target (if it's not already cached).
For more details, see the commit which added fscrypt_symlink_getattr().
Fixes: ca7f85be8d ("ubifs: Add support for encrypted symlinks")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210702065350.209646-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 461b43a8f92e68e96c4424b31e15f2b35f1bbfa9 upstream.
The stat() family of syscalls report the wrong size for encrypted
symlinks, which has caused breakage in several userspace programs.
Fix this by calling fscrypt_symlink_getattr() after f2fs_getattr() for
encrypted symlinks. This function computes the correct size by reading
and decrypting the symlink target (if it's not already cached).
For more details, see the commit which added fscrypt_symlink_getattr().
Fixes: cbaf042a3c ("f2fs crypto: add symlink encryption")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210702065350.209646-4-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8c4bca10ceafc43b1ca0a9fab5fa27e13cbce99e upstream.
The stat() family of syscalls report the wrong size for encrypted
symlinks, which has caused breakage in several userspace programs.
Fix this by calling fscrypt_symlink_getattr() after ext4_getattr() for
encrypted symlinks. This function computes the correct size by reading
and decrypting the symlink target (if it's not already cached).
For more details, see the commit which added fscrypt_symlink_getattr().
Fixes: f348c25232 ("ext4 crypto: add symlink encryption")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210702065350.209646-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d18760560593e5af921f51a8c9b64b6109d634c2 upstream.
Add a helper function fscrypt_symlink_getattr() which will be called
from the various filesystems' ->getattr() methods to read and decrypt
the target of encrypted symlinks in order to report the correct st_size.
Detailed explanation:
As required by POSIX and as documented in various man pages, st_size for
a symlink is supposed to be the length of the symlink target.
Unfortunately, st_size has always been wrong for encrypted symlinks
because st_size is populated from i_size from disk, which intentionally
contains the length of the encrypted symlink target. That's slightly
greater than the length of the decrypted symlink target (which is the
symlink target that userspace usually sees), and usually won't match the
length of the no-key encoded symlink target either.
This hadn't been fixed yet because reporting the correct st_size would
require reading the symlink target from disk and decrypting or encoding
it, which historically has been considered too heavyweight to do in
->getattr(). Also historically, the wrong st_size had only broken a
test (LTP lstat03) and there were no known complaints from real users.
(This is probably because the st_size of symlinks isn't used too often,
and when it is, typically it's for a hint for what buffer size to pass
to readlink() -- which a slightly-too-large size still works for.)
However, a couple things have changed now. First, there have recently
been complaints about the current behavior from real users:
- Breakage in rpmbuild:
https://github.com/rpm-software-management/rpm/issues/1682https://github.com/google/fscrypt/issues/305
- Breakage in toybox cpio:
https://www.mail-archive.com/toybox@lists.landley.net/msg07193.html
- Breakage in libgit2: https://issuetracker.google.com/issues/189629152
(on Android public issue tracker, requires login)
Second, we now cache decrypted symlink targets in ->i_link. Therefore,
taking the performance hit of reading and decrypting the symlink target
in ->getattr() wouldn't be as big a deal as it used to be, since usually
it will just save having to do the same thing later.
Also note that eCryptfs ended up having to read and decrypt symlink
targets in ->getattr() as well, to fix this same issue; see
commit 3a60a1686f ("eCryptfs: Decrypt symlink target for stat size").
So, let's just bite the bullet, and read and decrypt the symlink target
in ->getattr() in order to report the correct st_size. Add a function
fscrypt_symlink_getattr() which the filesystems will call to do this.
(Alternatively, we could store the decrypted size of symlinks on-disk.
But there isn't a great place to do so, and encryption is meant to hide
the original size to some extent; that property would be lost.)
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210702065350.209646-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fe67f4dd8daa252eb9aa7acb61555f3cc3c1ce4c upstream.
It turns out that the SIGIO/FASYNC situation is almost exactly the same
as the EPOLLET case was: user space really wants to be notified after
every operation.
Now, in a perfect world it should be sufficient to only notify user
space on "state transitions" when the IO state changes (ie when a pipe
goes from unreadable to readable, or from unwritable to writable). User
space should then do as much as possible - fully emptying the buffer or
what not - and we'll notify it again the next time the state changes.
But as with EPOLLET, we have at least one case (stress-ng) where the
kernel sent SIGIO due to the pipe being marked for asynchronous
notification, but the user space signal handler then didn't actually
necessarily read it all before returning (it read more than what was
written, but since there could be multiple writes, it could leave data
pending).
The user space code then expected to get another SIGIO for subsequent
writes - even though the pipe had been readable the whole time - and
would only then read more.
This is arguably a user space bug - and Colin King already fixed the
stress-ng code in question - but the kernel regression rules are clear:
it doesn't matter if kernel people think that user space did something
silly and wrong. What matters is that it used to work.
So if user space depends on specific historical kernel behavior, it's a
regression when that behavior changes. It's on us: we were silly to
have that non-optimal historical behavior, and our old kernel behavior
was what user space was tested against.
Because of how the FASYNC notification was tied to wakeup behavior, this
was first broken by commits f467a6a664 and 1b6b26ae70 ("pipe: fix
and clarify pipe read/write wakeup logic"), but at the time it seems
nobody noticed. Probably because the stress-ng problem case ends up
being timing-dependent too.
It was then unwittingly fixed by commit 3a34b13a88ca ("pipe: make pipe
writes always wake up readers") only to be broken again when by commit
3b844826b6c6 ("pipe: avoid unnecessary EPOLLET wakeups under normal
loads").
And at that point the kernel test robot noticed the performance
refression in the stress-ng.sigio.ops_per_sec case. So the "Fixes" tag
below is somewhat ad hoc, but it matches when the issue was noticed.
Fix it for good (knock wood) by simply making the kill_fasync() case
separate from the wakeup case. FASYNC is quite rare, and we clearly
shouldn't even try to use the "avoid unnecessary wakeups" logic for it.
Link: https://lore.kernel.org/lkml/20210824151337.GC27667@xsang-OptiPlex-9020/
Fixes: 3b844826b6c6 ("pipe: avoid unnecessary EPOLLET wakeups under normal loads")
Reported-by: kernel test robot <oliver.sang@intel.com>
Tested-by: Oliver Sang <oliver.sang@intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3b844826b6c6affa80755254da322b017358a2f4 upstream.
I had forgotten just how sensitive hackbench is to extra pipe wakeups,
and commit 3a34b13a88ca ("pipe: make pipe writes always wake up
readers") ended up causing a quite noticeable regression on larger
machines.
Now, hackbench isn't necessarily a hugely meaningful benchmark, and it's
not clear that this matters in real life all that much, but as Mel
points out, it's used often enough when comparing kernels and so the
performance regression shows up like a sore thumb.
It's easy enough to fix at least for the common cases where pipes are
used purely for data transfer, and you never have any exciting poll
usage at all. So set a special 'poll_usage' flag when there is polling
activity, and make the ugly "EPOLLET has crazy legacy expectations"
semantics explicit to only that case.
I would love to limit it to just the broken EPOLLET case, but the pipe
code can't see the difference between epoll and regular select/poll, so
any non-read/write waiting will trigger the extra wakeup behavior. That
is sufficient for at least the hackbench case.
Apart from making the odd extra wakeup cases more explicitly about
EPOLLET, this also makes the extra wakeup be at the _end_ of the pipe
write, not at the first write chunk. That is actually much saner
semantics (as much as you can call any of the legacy edge-triggered
expectations for EPOLLET "sane") since it means that you know the wakeup
will happen once the write is done, rather than possibly in the middle
of one.
[ For stable people: I'm putting a "Fixes" tag on this, but I leave it
up to you to decide whether you actually want to backport it or not.
It likely has no impact outside of synthetic benchmarks - Linus ]
Link: https://lore.kernel.org/lkml/20210802024945.GA8372@xsang-OptiPlex-9020/
Fixes: 3a34b13a88ca ("pipe: make pipe writes always wake up readers")
Reported-by: kernel test robot <oliver.sang@intel.com>
Tested-by: Sandeep Patil <sspatil@android.com>
Tested-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bc0939fcfab0d7efb2ed12896b1af3d819954a14 upstream.
We have a race between marking that an inode needs to be logged, either
at btrfs_set_inode_last_trans() or at btrfs_page_mkwrite(), and between
btrfs_sync_log(). The following steps describe how the race happens.
1) We are at transaction N;
2) Inode I was previously fsynced in the current transaction so it has:
inode->logged_trans set to N;
3) The inode's root currently has:
root->log_transid set to 1
root->last_log_commit set to 0
Which means only one log transaction was committed to far, log
transaction 0. When a log tree is created we set ->log_transid and
->last_log_commit of its parent root to 0 (at btrfs_add_log_tree());
4) One more range of pages is dirtied in inode I;
5) Some task A starts an fsync against some other inode J (same root), and
so it joins log transaction 1.
Before task A calls btrfs_sync_log()...
6) Task B starts an fsync against inode I, which currently has the full
sync flag set, so it starts delalloc and waits for the ordered extent
to complete before calling btrfs_inode_in_log() at btrfs_sync_file();
7) During ordered extent completion we have btrfs_update_inode() called
against inode I, which in turn calls btrfs_set_inode_last_trans(),
which does the following:
spin_lock(&inode->lock);
inode->last_trans = trans->transaction->transid;
inode->last_sub_trans = inode->root->log_transid;
inode->last_log_commit = inode->root->last_log_commit;
spin_unlock(&inode->lock);
So ->last_trans is set to N and ->last_sub_trans set to 1.
But before setting ->last_log_commit...
8) Task A is at btrfs_sync_log():
- it increments root->log_transid to 2
- starts writeback for all log tree extent buffers
- waits for the writeback to complete
- writes the super blocks
- updates root->last_log_commit to 1
It's a lot of slow steps between updating root->log_transid and
root->last_log_commit;
9) The task doing the ordered extent completion, currently at
btrfs_set_inode_last_trans(), then finally runs:
inode->last_log_commit = inode->root->last_log_commit;
spin_unlock(&inode->lock);
Which results in inode->last_log_commit being set to 1.
The ordered extent completes;
10) Task B is resumed, and it calls btrfs_inode_in_log() which returns
true because we have all the following conditions met:
inode->logged_trans == N which matches fs_info->generation &&
inode->last_subtrans (1) <= inode->last_log_commit (1) &&
inode->last_subtrans (1) <= root->last_log_commit (1) &&
list inode->extent_tree.modified_extents is empty
And as a consequence we return without logging the inode, so the
existing logged version of the inode does not point to the extent
that was written after the previous fsync.
It should be impossible in practice for one task be able to do so much
progress in btrfs_sync_log() while another task is at
btrfs_set_inode_last_trans() right after it reads root->log_transid and
before it reads root->last_log_commit. Even if kernel preemption is enabled
we know the task at btrfs_set_inode_last_trans() can not be preempted
because it is holding the inode's spinlock.
However there is another place where we do the same without holding the
spinlock, which is in the memory mapped write path at:
vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf)
{
(...)
BTRFS_I(inode)->last_trans = fs_info->generation;
BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
(...)
So with preemption happening after setting ->last_sub_trans and before
setting ->last_log_commit, it is less of a stretch to have another task
do enough progress at btrfs_sync_log() such that the task doing the memory
mapped write ends up with ->last_sub_trans and ->last_log_commit set to
the same value. It is still a big stretch to get there, as the task doing
btrfs_sync_log() has to start writeback, wait for its completion and write
the super blocks.
So fix this in two different ways:
1) For btrfs_set_inode_last_trans(), simply set ->last_log_commit to the
value of ->last_sub_trans minus 1;
2) For btrfs_page_mkwrite() only set the inode's ->last_sub_trans, just
like we do for buffered and direct writes at btrfs_file_write_iter(),
which is all we need to make sure multiple writes and fsyncs to an
inode in the same transaction never result in an fsync missing that
the inode changed and needs to be logged. Turn this into a helper
function and use it both at btrfs_page_mkwrite() and at
btrfs_file_write_iter() - this also fixes the problem that at
btrfs_page_mkwrite() we were setting those fields without the
protection of the inode's spinlock.
This is an extremely unlikely race to happen in practice.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4e9655763b82a91e4c341835bb504a2b1590f984 upstream.
This reverts commit f2165627319ffd33a6217275e5690b1ab5c45763.
[BUG]
It's no longer possible to create compressed inline extent after commit
f2165627319f ("btrfs: compression: don't try to compress if we don't
have enough pages").
[CAUSE]
For compression code, there are several possible reasons we have a range
that needs to be compressed while it's no more than one page.
- Compressed inline write
The data is always smaller than one sector and the test lacks the
condition to properly recognize a non-inline extent.
- Compressed subpage write
For the incoming subpage compressed write support, we require page
alignment of the delalloc range.
And for 64K page size, we can compress just one page into smaller
sectors.
For those reasons, the requirement for the data to be more than one page
is not correct, and is already causing regression for compressed inline
data writeback. The idea of skipping one page to avoid wasting CPU time
could be revisited in the future.
[FIX]
Fix it by reverting the offending commit.
Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Link: https://lore.kernel.org/linux-btrfs/afa2742.c084f5d6.17b6b08dffc@tnonline.net
Fixes: f2165627319f ("btrfs: compression: don't try to compress if we don't have enough pages")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 580c610429b3994e8db24418927747cf28443cde ]
One error path can result in release_dentry_name_snapshot() being called
before "name" was initialized by take_dentry_name_snapshot().
Fix by moving the release_dentry_name_snapshot() to immediately after the
only use.
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ upstream commit 21f965221e7c42609521342403e8fb91b8b3e76e ]
If an SQPOLL based ring is newly created and an application issues an
io_uring_enter(2) system call on it, then we can return a spurious
-EOWNERDEAD error. This happens because there's nothing to submit, and
if the caller doesn't specify any other action, the initial error
assignment of -EOWNERDEAD never gets overwritten. This causes us to
return it directly, even if it isn't valid.
Move the error assignment into the actual failure case instead.
Cc: stable@vger.kernel.org
Fixes: d9d05217cb69 ("io_uring: stop SQPOLL submit on creator's death")
Reported-by: Sherlock Holo sherlockya@gmail.com
Link: https://github.com/axboe/liburing/issues/413
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ upstream commit a30f895ad3239f45012e860d4f94c1a388b36d14 ]
We currently check for ret != 0 to indicate error, but '1' is a valid
return and just indicates that the allocation succeeded with a wrap.
Correct the check to be for < 0, like it was before the xarray
conversion.
Cc: stable@vger.kernel.org
Fixes: 61cf93700fe6 ("io_uring: Convert personality_idr to XArray")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fdd92b64d15bc4aec973caa25899afd782402e68 ]
We've had CONFIG_MANDATORY_FILE_LOCKING since 2015 and a lot of distros
have disabled it. Warn the stragglers that still use "-o mand" that
we'll be dropping support for that mount option.
Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 52dfd86aa568e433b24357bb5fc725560f1e22d8 upstream.
Opening a new file is done in 2 steps on regular filesystems:
1. Call the create inode-op on the parent-dir to create an inode
to hold the meta-data related to the file.
2. Call the open file-op to get a handle for the file.
vboxsf however does not really use disk-backed inodes because it
is based on passing through file-related system-calls through to
the hypervisor. So both steps translate to an open(2) call being
passed through to the hypervisor. With the handle returned by
the first call immediately being closed again.
Making 2 open calls for a single open(..., O_CREATE, ...) calls
has 2 problems:
a) It is not really efficient.
b) It actually breaks some apps.
An example of b) is doing a git clone inside a vboxsf mount.
When git clone tries to create a tempfile to store the pak
files which is downloading the following happens:
1. vboxsf_dir_mkfile() gets called with a mode of 0444 and succeeds.
2. vboxsf_file_open() gets called with file->f_flags containing
O_RDWR. When the host is a Linux machine this fails because doing
a open(..., O_RDWR) on a file which exists and has mode 0444 results
in an -EPERM error.
Other network-filesystems and fuse avoid the problem of needing to
pass 2 open() calls to the other side by using the atomic_open
directory-inode op.
This commit fixes git clone not working inside a vboxsf mount,
by adding support for the atomic_open directory-inode op.
As an added bonus this should also make opening new files faster.
The atomic_open implementation is modelled after the atomic_open
implementations from the 9p and fuse code.
Fixes: 0fd1695766 ("fs: Add VirtualBox guest shared folder (vboxsf) support")
Reported-by: Ludovic Pouzenc <bugreports@pouzenc.fr>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 02f840f90764f22f5c898901849bdbf0cee752ba upstream.
Factor out the code to create / release a struct vboxsf_handle into
2 new helper functions.
This is a preparation patch for adding atomic_open support.
Fixes: 0fd1695766 ("fs: Add VirtualBox guest shared folder (vboxsf) support")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7d3fc01796fc895e5fcce45c994c5a8db8120a8d upstream.
We used to follow the rule earlier that the create SD context
always be a multiple of 8. However, with the change:
cifs: refactor create_sd_buf() and and avoid corrupting the buffer
...we recompute the length, and we failed that rule.
Fixing that with this change.
Cc: <stable@vger.kernel.org> # v5.10+
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ab0c29687bc7a890d1a86ac376b0b0fd78b2d9b6 upstream
Make vboxsf_dir_create() optionally return the vboxsf-handle for
the created file. This is a preparation patch for adding atomic_open
support.
Fixes: 0fd1695766 ("fs: Add VirtualBox guest shared folder (vboxsf) support")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cc3ddee97cff034cea4d095de4a484c92a219bf5 upstream
Honor the excl flag to the dir-inode create op, instead of behaving
as if it is always set.
Note the old behavior still worked most of the time since a non-exclusive
open only calls the create op, if there is a race and the file is created
between the dentry lookup and the calling of the create call.
While at it change the type of the is_dir parameter to the
vboxsf_dir_create() helper from an int to a bool, to be consistent with
the use of bool for the excl parameter.
Fixes: 0fd1695766 ("fs: Add VirtualBox guest shared folder (vboxsf) support")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5ad4df56cd2158965f73416d41fce37906724822 ]
Clang detected a problem with rc possibly being unitialized
(when length is zero) in a recently added fallocate code path.
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 13d257503c0930010ef9eed78b689cec417ab741 ]
While verifying the leaf item that we read from the disk, reiserfs
doesn't check the directory items, this could cause a crash when we
read a directory item from the disk that has an invalid deh_location.
This patch adds a check to the directory items read from the disk that
does a bounds check on deh_location for the directory entries. Any
directory entry header with a directory entry offset greater than the
item length is considered invalid.
Link: https://lore.kernel.org/r/20210709152929.766363-1-chouhan.shreyansh630@gmail.com
Reported-by: syzbot+c31a48e6702ccb3d64c9@syzkaller.appspotmail.com
Signed-off-by: Shreyansh Chouhan <chouhan.shreyansh630@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 877ba3f729fd3d8ef0e29bc2a55e57cfa54b2e43 upstream.
Commit b5776e7524af ("ext4: fix potential htree index checksum
corruption) removed a required restart when multiple levels of index
nodes need to be split. Fix this to avoid directory htree corruptions
when using the large_dir feature.
Cc: stable@kernel.org # v5.11
Cc: Благодаренко Артём <artem.blagodarenko@gmail.com>
Fixes: b5776e7524af ("ext4: fix potential htree index checksum corruption)
Reported-by: Denis <denis@voxelsoft.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 46c4c9d1beb7f5b4cec4dd90e7728720583ee348 upstream.
This program always prints 4096 and hangs before the patch, and always
prints 8192 and exits successfully after:
int main()
{
int pipefd[2];
for (int i = 0; i < 1025; i++)
if (pipe(pipefd) == -1)
return 1;
size_t bufsz = fcntl(pipefd[1], F_GETPIPE_SZ);
printf("%zd\n", bufsz);
char *buf = calloc(bufsz, 1);
write(pipefd[1], buf, bufsz);
read(pipefd[0], buf, bufsz-1);
write(pipefd[1], buf, 1);
}
Note that you may need to increase your RLIMIT_NOFILE before running the
program.
Fixes: 759c01142a ("pipe: limit the per-user amount of pages allocated in pipes")
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/lkml/1628086770.5rn8p04n6j.none@localhost/
Link: https://lore.kernel.org/lkml/1628127094.lxxn016tj7.none@localhost/
Signed-off-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ecc64fab7d49c678e70bd4c35fe64d2ab3e3d212 ]
When checking if we need to log the new name of a renamed inode, we are
checking if the inode and its parent inode have been logged before, and if
not we don't log the new name. The check however is buggy, as it directly
compares the logged_trans field of the inodes versus the ID of the current
transaction. The problem is that logged_trans is a transient field, only
stored in memory and never persisted in the inode item, so if an inode
was logged before, evicted and reloaded, its logged_trans field is set to
a value of 0, meaning the check will return false and the new name of the
renamed inode is not logged. If the old parent directory was previously
fsynced and we deleted the logged directory entries corresponding to the
old name, we end up with a log that when replayed will delete the renamed
inode.
The following example triggers the problem:
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt
$ mkdir /mnt/A
$ mkdir /mnt/B
$ echo -n "hello world" > /mnt/A/foo
$ sync
# Add some new file to A and fsync directory A.
$ touch /mnt/A/bar
$ xfs_io -c "fsync" /mnt/A
# Now trigger inode eviction. We are only interested in triggering
# eviction for the inode of directory A.
$ echo 2 > /proc/sys/vm/drop_caches
# Move foo from directory A to directory B.
# This deletes the directory entries for foo in A from the log, and
# does not add the new name for foo in directory B to the log, because
# logged_trans of A is 0, which is less than the current transaction ID.
$ mv /mnt/A/foo /mnt/B/foo
# Now make an fsync to anything except A, B or any file inside them,
# like for example create a file at the root directory and fsync this
# new file. This syncs the log that contains all the changes done by
# previous rename operation.
$ touch /mnt/baz
$ xfs_io -c "fsync" /mnt/baz
<power fail>
# Mount the filesystem and replay the log.
$ mount /dev/sdc /mnt
# Check the filesystem content.
$ ls -1R /mnt
/mnt/:
A
B
baz
/mnt/A:
bar
/mnt/B:
$
# File foo is gone, it's neither in A/ nor in B/.
Fix this by using the inode_logged() helper at btrfs_log_new_name(), which
safely checks if an inode was logged before in the current transaction.
A test case for fstests will follow soon.
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f2a26a3cff27dfa456fef386fe5df56dcb4b47b6 upstream.
readpage was calculating the offset of the page incorrectly
for the case of large swapcaches.
loff_t offset = (loff_t)page->index << PAGE_SHIFT;
As pointed out by Matthew Wilcox, this needs to use
page_file_offset() to calculate the offset instead.
Pages coming from the swap cache have page->index set
to their index within the swapcache, not within the backing
file. For a sufficiently large swapcache, we could have
overlapping values of page->index within the same backing file.
Suggested by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org> # v5.7+
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9449ad33be8480f538b11a593e2dda2fb33ca06d upstream.
For punch holes in EOF blocks, fallocate used buffer write to zero the
EOF blocks in last cluster. But since ->writepage will ignore EOF
pages, those zeros will not be flushed.
This "looks" ok as commit 6bba4471f0cc ("ocfs2: fix data corruption by
fallocate") will zero the EOF blocks when extend the file size, but it
isn't. The problem happened on those EOF pages, before writeback, those
pages had DIRTY flag set and all buffer_head in them also had DIRTY flag
set, when writeback run by write_cache_pages(), DIRTY flag on the page
was cleared, but DIRTY flag on the buffer_head not.
When next write happened to those EOF pages, since buffer_head already
had DIRTY flag set, it would not mark page DIRTY again. That made
writeback ignore them forever. That will cause data corruption. Even
directio write can't work because it will fail when trying to drop pages
caches before direct io, as it found the buffer_head for those pages
still had DIRTY flag set, then it will fall back to buffer io mode.
To make a summary of the issue, as writeback ingores EOF pages, once any
EOF page is generated, any write to it will only go to the page cache,
it will never be flushed to disk even file size extends and that page is
not EOF page any more. The fix is to avoid zero EOF blocks with buffer
write.
The following code snippet from qemu-img could trigger the corruption.
656 open("6b3711ae-3306-4bdd-823c-cf1c0060a095.conv.2", O_RDWR|O_DIRECT|O_CLOEXEC) = 11
...
660 fallocate(11, FALLOC_FL_KEEP_SIZE|FALLOC_FL_PUNCH_HOLE, 2275868672, 327680 <unfinished ...>
660 fallocate(11, 0, 2275868672, 327680) = 0
658 pwrite64(11, "
Link: https://lkml.kernel.org/r/20210722054923.24389-2-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.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>
commit f267aeb6dea5e468793e5b8eb6a9c72c0020d418 upstream.
If append-dio feature is enabled, direct-io write and fallocate could
run in parallel to extend file size, fallocate used "orig_isize" to
record i_size before taking "ip_alloc_sem", when
ocfs2_zeroout_partial_cluster() zeroout EOF blocks, i_size maybe already
extended by ocfs2_dio_end_io_write(), that will cause valid data zeroed
out.
Link: https://lkml.kernel.org/r/20210722054923.24389-1-junxiao.bi@oracle.com
Fixes: 6bba4471f0cc ("ocfs2: fix data corruption by fallocate")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mark@fasheh.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>
commit 240246f6b913b0c23733cfd2def1d283f8cc9bbe upstream.
In compression write endio sequence, the range which the compressed_bio
writes is marked as uptodate if the last bio of the compressed (sub)bios
is completed successfully. There could be previous bio which may
have failed which is recorded in cb->errors.
Set the writeback range as uptodate only if cb->errors is zero, as opposed
to checking only the last bio's status.
Backporting notes: in all versions up to 4.4 the last argument is always
replaced by "!cb->errors".
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b2a616676839e2a6b02c8e40be7f886f882ed194 upstream.
When removing a writeable device in __btrfs_free_extra_devids, the rw
device count should be decremented.
This error was caught by Syzbot which reported a warning in
close_fs_devices:
WARNING: CPU: 1 PID: 9355 at fs/btrfs/volumes.c:1168 close_fs_devices+0x763/0x880 fs/btrfs/volumes.c:1168
Modules linked in:
CPU: 0 PID: 9355 Comm: syz-executor552 Not tainted 5.13.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:close_fs_devices+0x763/0x880 fs/btrfs/volumes.c:1168
RSP: 0018:ffffc9000333f2f0 EFLAGS: 00010293
RAX: ffffffff8365f5c3 RBX: 0000000000000001 RCX: ffff888029afd4c0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88802846f508 R08: ffffffff8365f525 R09: ffffed100337d128
R10: ffffed100337d128 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888019be8868 R14: 1ffff1100337d10d R15: 1ffff1100337d10a
FS: 00007f6f53828700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000047c410 CR3: 00000000302a6000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
btrfs_close_devices+0xc9/0x450 fs/btrfs/volumes.c:1180
open_ctree+0x8e1/0x3968 fs/btrfs/disk-io.c:3693
btrfs_fill_super fs/btrfs/super.c:1382 [inline]
btrfs_mount_root+0xac5/0xc60 fs/btrfs/super.c:1749
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1498
fc_mount fs/namespace.c:993 [inline]
vfs_kern_mount+0xc9/0x160 fs/namespace.c:1023
btrfs_mount+0x3d3/0xb50 fs/btrfs/super.c:1809
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1498
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x196f/0x2be0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
Because fs_devices->rw_devices was not 0 after
closing all devices. Here is the call trace that was observed:
btrfs_mount_root():
btrfs_scan_one_device():
device_list_add(); <---------------- device added
btrfs_open_devices():
open_fs_devices():
btrfs_open_one_device(); <-------- writable device opened,
rw device count ++
btrfs_fill_super():
open_ctree():
btrfs_free_extra_devids():
__btrfs_free_extra_devids(); <--- writable device removed,
rw device count not decremented
fail_tree_roots:
btrfs_close_devices():
close_fs_devices(); <------- rw device count off by 1
As a note, prior to commit cf89af146b ("btrfs: dev-replace: fail
mount if we don't have replace item with target device"), rw_devices
was decremented on removing a writable device in
__btrfs_free_extra_devids only if the BTRFS_DEV_STATE_REPLACE_TGT bit
was not set for the device. However, this check does not need to be
reinstated as it is now redundant and incorrect.
In __btrfs_free_extra_devids, we skip removing the device if it is the
target for replacement. This is done by checking whether device->devid
== BTRFS_DEV_REPLACE_DEVID. Since BTRFS_DEV_STATE_REPLACE_TGT is set
only on the device with devid BTRFS_DEV_REPLACE_DEVID, no devices
should have the BTRFS_DEV_STATE_REPLACE_TGT bit set after the check,
and so it's redundant to test for that bit.
Additionally, following commit 82372bc816 ("Btrfs: make
the logic of source device removing more clear"), rw_devices is
incremented whenever a writeable device is added to the alloc
list (including the target device in btrfs_dev_replace_finishing), so
all removals of writable devices from the alloc list should also be
accompanied by a decrement to rw_devices.
Reported-by: syzbot+a70e2ad0879f160b9217@syzkaller.appspotmail.com
Fixes: cf89af146b ("btrfs: dev-replace: fail mount if we don't have replace item with target device")
CC: stable@vger.kernel.org # 5.10+
Tested-by: syzbot+a70e2ad0879f160b9217@syzkaller.appspotmail.com
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3a34b13a88caeb2800ab44a4918f230041b37dd9 upstream.
Since commit 1b6b26ae70 ("pipe: fix and clarify pipe write wakeup
logic") we have sanitized the pipe write logic, and would only try to
wake up readers if they needed it.
In particular, if the pipe already had data in it before the write,
there was no point in trying to wake up a reader, since any existing
readers must have been aware of the pre-existing data already. Doing
extraneous wakeups will only cause potential thundering herd problems.
However, it turns out that some Android libraries have misused the EPOLL
interface, and expected "edge triggered" be to "any new write will
trigger it". Even if there was no edge in sight.
Quoting Sandeep Patil:
"The commit 1b6b26ae70 ('pipe: fix and clarify pipe write wakeup
logic') changed pipe write logic to wakeup readers only if the pipe
was empty at the time of write. However, there are libraries that
relied upon the older behavior for notification scheme similar to
what's described in [1]
One such library 'realm-core'[2] is used by numerous Android
applications. The library uses a similar notification mechanism as GNU
Make but it never drains the pipe until it is full. When Android moved
to v5.10 kernel, all applications using this library stopped working.
The library has since been fixed[3] but it will be a while before all
applications incorporate the updated library"
Our regression rule for the kernel is that if applications break from
new behavior, it's a regression, even if it was because the application
did something patently wrong. Also note the original report [4] by
Michal Kerrisk about a test for this epoll behavior - but at that point
we didn't know of any actual broken use case.
So add the extraneous wakeup, to approximate the old behavior.
[ I say "approximate", because the exact old behavior was to do a wakeup
not for each write(), but for each pipe buffer chunk that was filled
in. The behavior introduced by this change is not that - this is just
"every write will cause a wakeup, whether necessary or not", which
seems to be sufficient for the broken library use. ]
It's worth noting that this adds the extraneous wakeup only for the
write side, while the read side still considers the "edge" to be purely
about reading enough from the pipe to allow further writes.
See commit f467a6a664 ("pipe: fix and clarify pipe read wakeup logic")
for the pipe read case, which remains that "only wake up if the pipe was
full, and we read something from it".
Link: https://lore.kernel.org/lkml/CAHk-=wjeG0q1vgzu4iJhW5juPkTsjTYmiqiMUYAebWW+0bam6w@mail.gmail.com/ [1]
Link: https://github.com/realm/realm-core [2]
Link: https://github.com/realm/realm-core/issues/4666 [3]
Link: https://lore.kernel.org/lkml/CAKgNAkjMBGeAwF=2MKK758BhxvW58wYTgYKB2V-gY1PwXxrH+Q@mail.gmail.com/ [4]
Link: https://lore.kernel.org/lkml/20210729222635.2937453-1-sspatil@android.com/
Reported-by: Sandeep Patil <sspatil@android.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 49694d14ff68fa4b5f86019dbcfb44a8bd213e58 ]
The length variable is rather pointless given that it can be trivially
deduced from offset and size. Also the initial calculation can lead
to KASAN warnings.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Leizhen (ThunderTown) <thunder.leizhen@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3ac1d426510f97ace05093ae9f2f710d9cbe6215 ]
The length variable is rather pointless given that it can be trivially
deduced from offset and size. Also the initial calculation can lead
to KASAN warnings.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Leizhen (ThunderTown) <thunder.leizhen@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c9c9c6815f9004ee1ec87401ed0796853bd70f1b ]
Because the out of range assignment to bit fields
are compiler-dependant, the fields could have wrong
value.
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b3b2177a2d795e35dc11597b2609eb1e7e57e570 ]
Syzbot reports a possible recursive lock in [1].
This happens due to missing lock nesting information. From the logs, we
see that a call to hfs_fill_super is made to mount the hfs filesystem.
While searching for the root inode, the lock on the catalog btree is
grabbed. Then, when the parent of the root isn't found, a call to
__hfs_bnode_create is made to create the parent of the root. This
eventually leads to a call to hfs_ext_read_extent which grabs a lock on
the extents btree.
Since the order of locking is catalog btree -> extents btree, this lock
hierarchy does not lead to a deadlock.
To tell lockdep that this locking is safe, we add nesting notation to
distinguish between catalog btrees, extents btrees, and attributes
btrees (for HFS+). This has already been done in hfsplus.
Link: https://syzkaller.appspot.com/bug?id=f007ef1d7a31a469e3be7aeb0fde0769b18585db [1]
Link: https://lkml.kernel.org/r/20210701030756.58760-4-desmondcheongzx@gmail.com
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Reported-by: syzbot+b718ec84a87b7e73ade4@syzkaller.appspotmail.com
Tested-by: syzbot+b718ec84a87b7e73ade4@syzkaller.appspotmail.com
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 16ee572eaf0d09daa4c8a755fdb71e40dbf8562d ]
Patch series "hfs: fix various errors", v2.
This series ultimately aims to address a lockdep warning in
hfs_find_init reported by Syzbot [1].
The work done for this led to the discovery of another bug, and the
Syzkaller repro test also reveals an invalid memory access error after
clearing the lockdep warning. Hence, this series is broken up into
three patches:
1. Add a missing call to hfs_find_exit for an error path in
hfs_fill_super
2. Fix memory mapping in hfs_bnode_read by fixing calls to kmap
3. Add lock nesting notation to tell lockdep that the observed locking
hierarchy is safe
This patch (of 3):
Before exiting hfs_fill_super, the struct hfs_find_data used in
hfs_find_init should be passed to hfs_find_exit to be cleaned up, and to
release the lock held on the btree.
The call to hfs_find_exit is missing from an error path. We add it back
in by consolidating calls to hfs_find_exit for error paths.
Link: https://syzkaller.appspot.com/bug?id=f007ef1d7a31a469e3be7aeb0fde0769b18585db [1]
Link: https://lkml.kernel.org/r/20210701030756.58760-1-desmondcheongzx@gmail.com
Link: https://lkml.kernel.org/r/20210701030756.58760-2-desmondcheongzx@gmail.com
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 1e7107c5ef44431bc1ebbd4c353f1d7c22e5f2ec upstream.
Richard reported sporadic (roughly one in 10 or so) null dereferences and
other strange behaviour for a set of automated LTP tests. Things like:
BUG: kernel NULL pointer dereference, address: 0000000000000008
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 0 PID: 1516 Comm: umount Not tainted 5.10.0-yocto-standard #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-48-gd9c812dda519-prebuilt.qemu.org 04/01/2014
RIP: 0010:kernfs_sop_show_path+0x1b/0x60
...or these others:
RIP: 0010:do_mkdirat+0x6a/0xf0
RIP: 0010:d_alloc_parallel+0x98/0x510
RIP: 0010:do_readlinkat+0x86/0x120
There were other less common instances of some kind of a general scribble
but the common theme was mount and cgroup and a dubious dentry triggering
the NULL dereference. I was only able to reproduce it under qemu by
replicating Richard's setup as closely as possible - I never did get it
to happen on bare metal, even while keeping everything else the same.
In commit 71d883c37e ("cgroup_do_mount(): massage calling conventions")
we see this as a part of the overall change:
--------------
struct cgroup_subsys *ss;
- struct dentry *dentry;
[...]
- dentry = cgroup_do_mount(&cgroup_fs_type, fc->sb_flags, root,
- CGROUP_SUPER_MAGIC, ns);
[...]
- if (percpu_ref_is_dying(&root->cgrp.self.refcnt)) {
- struct super_block *sb = dentry->d_sb;
- dput(dentry);
+ ret = cgroup_do_mount(fc, CGROUP_SUPER_MAGIC, ns);
+ if (!ret && percpu_ref_is_dying(&root->cgrp.self.refcnt)) {
+ struct super_block *sb = fc->root->d_sb;
+ dput(fc->root);
deactivate_locked_super(sb);
msleep(10);
return restart_syscall();
}
--------------
In changing from the local "*dentry" variable to using fc->root, we now
export/leave that dentry pointer in the file context after doing the dput()
in the unlikely "is_dying" case. With LTP doing a crazy amount of back to
back mount/unmount [testcases/bin/cgroup_regression_5_1.sh] the unlikely
becomes slightly likely and then bad things happen.
A fix would be to not leave the stale reference in fc->root as follows:
--------------
dput(fc->root);
+ fc->root = NULL;
deactivate_locked_super(sb);
--------------
...but then we are just open-coding a duplicate of fc_drop_locked() so we
simply use that instead.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: stable@vger.kernel.org # v5.1+
Reported-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Fixes: 71d883c37e ("cgroup_do_mount(): massage calling conventions")
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e0f7e2b2f7e7864238a4eea05cc77ae1be2bf784 upstream.
In commit 32021982a3 ("hugetlbfs: Convert to fs_context") processing
of the mount mode string was changed from match_octal() to fsparam_u32.
This changed existing behavior as match_octal does not require octal
values to have a '0' prefix, but fsparam_u32 does.
Use fsparam_u32oct which provides the same behavior as match_octal.
Link: https://lkml.kernel.org/r/20210721183326.102716-1-mike.kravetz@oracle.com
Fixes: 32021982a3 ("hugetlbfs: Convert to fs_context")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Dennis Camera <bugs+kernel.org@dtnr.ch>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
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>
commit e71e2ace5721a8b921dca18b045069e7bb411277 upstream.
Patch series "userfaultfd: do not untag user pointers", v5.
If a user program uses userfaultfd on ranges of heap memory, it may end
up passing a tagged pointer to the kernel in the range.start field of
the UFFDIO_REGISTER ioctl. This can happen when using an MTE-capable
allocator, or on Android if using the Tagged Pointers feature for MTE
readiness [1].
When a fault subsequently occurs, the tag is stripped from the fault
address returned to the application in the fault.address field of struct
uffd_msg. However, from the application's perspective, the tagged
address *is* the memory address, so if the application is unaware of
memory tags, it may get confused by receiving an address that is, from
its point of view, outside of the bounds of the allocation. We observed
this behavior in the kselftest for userfaultfd [2] but other
applications could have the same problem.
Address this by not untagging pointers passed to the userfaultfd ioctls.
Instead, let the system call fail. Also change the kselftest to use
mmap so that it doesn't encounter this problem.
[1] https://source.android.com/devices/tech/debug/tagged-pointers
[2] tools/testing/selftests/vm/userfaultfd.c
This patch (of 2):
Do not untag pointers passed to the userfaultfd ioctls. Instead, let
the system call fail. This will provide an early indication of problems
with tag-unaware userspace code instead of letting the code get confused
later, and is consistent with how we decided to handle brk/mmap/mremap
in commit dcde237319 ("mm: Avoid creating virtual address aliases in
brk()/mmap()/mremap()"), as well as being consistent with the existing
tagged address ABI documentation relating to how ioctl arguments are
handled.
The code change is a revert of commit 7d0325749a ("userfaultfd: untag
user pointers") plus some fixups to some additional calls to
validate_range that have appeared since then.
[1] https://source.android.com/devices/tech/debug/tagged-pointers
[2] tools/testing/selftests/vm/userfaultfd.c
Link: https://lkml.kernel.org/r/20210714195437.118982-1-pcc@google.com
Link: https://lkml.kernel.org/r/20210714195437.118982-2-pcc@google.com
Link: https://linux-review.googlesource.com/id/I761aa9f0344454c482b83fcfcce547db0a25501b
Fixes: 63f0c60379 ("arm64: Introduce prctl() options to control the tagged user addresses ABI")
Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alistair Delva <adelva@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mitch Phillips <mitchp@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: William McVicker <willmcvicker@google.com>
Cc: <stable@vger.kernel.org> [5.4]
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>
commit 46fee9ab02cb24979bbe07631fc3ae95ae08aa3e upstream.
__io_queue_proc() can enqueue both poll entries and still fail
afterwards, so the callers trying to cancel it should also try to remove
the second poll entry (if any).
For example, it may leave the request alive referencing a io_uring
context but not accessible for cancellation:
[ 282.599913][ T1620] task:iou-sqp-23145 state:D stack:28720 pid:23155 ppid: 8844 flags:0x00004004
[ 282.609927][ T1620] Call Trace:
[ 282.613711][ T1620] __schedule+0x93a/0x26f0
[ 282.634647][ T1620] schedule+0xd3/0x270
[ 282.638874][ T1620] io_uring_cancel_generic+0x54d/0x890
[ 282.660346][ T1620] io_sq_thread+0xaac/0x1250
[ 282.696394][ T1620] ret_from_fork+0x1f/0x30
Cc: stable@vger.kernel.org
Fixes: 18bceab101 ("io_uring: allow POLL_ADD with double poll_wait() users")
Reported-and-tested-by: syzbot+ac957324022b7132accf@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0ec1228fc5eda4cb524eeda857da8efdc43c331c.1626774457.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 68b11e8b1562986c134764433af64e97d30c9fc0 upstream.
If __io_queue_proc() fails to add a second poll entry, e.g. kmalloc()
failed, but it goes on with a third waitqueue, it may succeed and
overwrite the error status. Count the number of poll entries we added,
so we can set pt->error to zero at the beginning and find out when the
mentioned scenario happens.
Cc: stable@vger.kernel.org
Fixes: 18bceab101 ("io_uring: allow POLL_ADD with double poll_wait() users")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9d6b9e561f88bcc0163623b74a76c39f712151c3.1626774457.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
