[ Upstream commit 936eba9cfb ]
open_cached_dir today selects ses->server a.k.a primary channel
to send requests. When multichannel is used, the primary
channel maybe down. So it does not make sense to rely only
on that channel.
This fix makes this function pick a channel with the standard
helper function cifs_pick_channel.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 5bc09b397c upstream.
According to a syzbot report, end_buffer_async_write(), which handles the
completion of block device writes, may detect abnormal condition of the
buffer async_write flag and cause a BUG_ON failure when using nilfs2.
Nilfs2 itself does not use end_buffer_async_write(). But, the async_write
flag is now used as a marker by commit 7f42ec3941 ("nilfs2: fix issue
with race condition of competition between segments for dirty blocks") as
a means of resolving double list insertion of dirty blocks in
nilfs_lookup_dirty_data_buffers() and nilfs_lookup_node_buffers() and the
resulting crash.
This modification is safe as long as it is used for file data and b-tree
node blocks where the page caches are independent. However, it was
irrelevant and redundant to also introduce async_write for segment summary
and super root blocks that share buffers with the backing device. This
led to the possibility that the BUG_ON check in end_buffer_async_write
would fail as described above, if independent writebacks of the backing
device occurred in parallel.
The use of async_write for segment summary buffers has already been
removed in a previous change.
Fix this issue by removing the manipulation of the async_write flag for
the remaining super root block buffer.
Link: https://lkml.kernel.org/r/20240203161645.4992-1-konishi.ryusuke@gmail.com
Fixes: 7f42ec3941 ("nilfs2: fix issue with race condition of competition between segments for dirty blocks")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+5c04210f7c7f897c1e7f@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/00000000000019a97c05fd42f8c8@google.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5ea9a7c5fe upstream.
A recent change to check_for_locks() changed it to take ->flc_lock while
holding ->fi_lock. This creates a lock inversion (reported by lockdep)
because there is a case where ->fi_lock is taken while holding
->flc_lock.
->flc_lock is held across ->fl_lmops callbacks, and
nfsd_break_deleg_cb() is one of those and does take ->fi_lock. However
it doesn't need to.
Prior to v4.17-rc1~110^2~22 ("nfsd: create a separate lease for each
delegation") nfsd_break_deleg_cb() would walk the ->fi_delegations list
and so needed the lock. Since then it doesn't walk the list and doesn't
need the lock.
Two actions are performed under the lock. One is to call
nfsd_break_one_deleg which calls nfsd4_run_cb(). These doesn't act on
the nfs4_file at all, so don't need the lock.
The other is to set ->fi_had_conflict which is in the nfs4_file.
This field is only ever set here (except when initialised to false)
so there is no possible problem will multiple threads racing when
setting it.
The field is tested twice in nfs4_set_delegation(). The first test does
not hold a lock and is documented as an opportunistic optimisation, so
it doesn't impose any need to hold ->fi_lock while setting
->fi_had_conflict.
The second test in nfs4_set_delegation() *is* make under ->fi_lock, so
removing the locking when ->fi_had_conflict is set could make a change.
The change could only be interesting if ->fi_had_conflict tested as
false even though nfsd_break_one_deleg() ran before ->fi_lock was
unlocked. i.e. while hash_delegation_locked() was running.
As hash_delegation_lock() doesn't interact in any way with nfs4_run_cb()
there can be no importance to this interaction.
So this patch removes the locking from nfsd_break_one_deleg() and moves
the final test on ->fi_had_conflict out of the locked region to make it
clear that locking isn't important to the test. It is still tested
*after* vfs_setlease() has succeeded. This might be significant and as
vfs_setlease() takes ->flc_lock, and nfsd_break_one_deleg() is called
under ->flc_lock this "after" is a true ordering provided by a spinlock.
Fixes: edcf972515 ("nfsd: fix RELEASE_LOCKOWNER")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ca185770db upstream.
The directory link count in eventfs was somewhat bogus. It was only being
updated when a directory child was being looked up and not on creation.
One solution would be to update in get_attr() the link count by iterating
the ei->children list and then adding 2. But that could slow down simple
stat() calls, especially if it's done on all directories in eventfs.
Another solution would be to add a parent pointer to the eventfs_inode
and keep track of the number of sub directories it has on creation. But
this adds overhead for something not really worthwhile.
The solution decided upon is to keep all directory links in eventfs as 1.
This tells user space not to rely on the hard links of directories. Which
in this case it shouldn't.
Link: https://lore.kernel.org/linux-trace-kernel/20240201002719.GS2087318@ZenIV/
Link: https://lore.kernel.org/linux-trace-kernel/20240201161617.339968298@goodmis.org
Cc: stable@vger.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Fixes: c1504e5102 ("eventfs: Implement eventfs dir creation functions")
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 12d823b31f upstream.
The dentries and inodes are created when referenced in the lookup code.
There's no reason to call fsnotify_*() functions when they are created by
a reference. It doesn't make any sense.
Link: https://lore.kernel.org/linux-trace-kernel/20240201002719.GS2087318@ZenIV/
Link: https://lore.kernel.org/linux-trace-kernel/20240201161617.166973329@goodmis.org
Cc: stable@vger.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Fixes: a376007917 ("eventfs: Implement functions to create files and dirs when accessed");
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 264424dfdd upstream.
Some of the eventfs_inode structure has holes in it. Rework the structure
to be a bit more condensed, and also remove the no longer used llist
field.
Link: https://lore.kernel.org/linux-trace-kernel/20240201161617.002321438@goodmis.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5a49f99604 upstream.
There should never be a case where an evenfs_inode is being freed without
is_freed being set. Add a WARN_ON_ONCE() if it ever happens. That would
mean there was one too many put_ei()s.
Link: https://lore.kernel.org/linux-trace-kernel/20240201161616.843551963@goodmis.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 43aa6f97c2 upstream.
The eventfs inode had pointers to dentries (and child dentries) without
actually holding a refcount on said pointer. That is fundamentally
broken, and while eventfs tried to then maintain coherence with dentries
going away by hooking into the '.d_iput' callback, that doesn't actually
work since it's not ordered wrt lookups.
There were two reasonms why eventfs tried to keep a pointer to a dentry:
- the creation of a 'events' directory would actually have a stable
dentry pointer that it created with tracefs_start_creating().
And it needed that dentry when tearing it all down again in
eventfs_remove_events_dir().
This use is actually ok, because the special top-level events
directory dentries are actually stable, not just a temporary cache of
the eventfs data structures.
- the 'eventfs_inode' (aka ei) needs to stay around as long as there
are dentries that refer to it.
It then used these dentry pointers as a replacement for doing
reference counting: it would try to make sure that there was only
ever one dentry associated with an event_inode, and keep a child
dentry array around to see which dentries might still refer to the
parent ei.
This gets rid of the invalid dentry pointer use, and renames the one
valid case to a different name to make it clear that it's not just any
random dentry.
The magic child dentry array that is kind of a "reverse reference list"
is simply replaced by having child dentries take a ref to the ei. As
does the directory dentries. That makes the broken use case go away.
Link: https://lore.kernel.org/linux-trace-kernel/202401291043.e62e89dc-oliver.sang@intel.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240131185513.280463000@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: c1504e5102 ("eventfs: Implement eventfs dir creation functions")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8dce06e98c upstream.
In order for the dentries to stay up-to-date with the eventfs changes,
just add a 'd_revalidate' function that checks the 'is_freed' bit.
Also, clean up the dentry release to actually use d_release() rather
than the slightly odd d_iput() function. We don't care about the inode,
all we want to do is to get rid of the refcount to the eventfs data
added by dentry->d_fsdata.
It would probably be cleaner to make eventfs its own filesystem, or at
least set its own dentry ops when looking up eventfs files. But as it
is, only eventfs dentries use d_fsdata, so we don't really need to split
these things up by use.
Another thing that might be worth doing is to make all eventfs lookups
mark their dentries as not worth caching. We could do that with
d_delete(), but the DCACHE_DONTCACHE flag would likely be even better.
As it is, the dentries are all freeable, but they only tend to get freed
at memory pressure rather than more proactively. But that's a separate
issue.
Link: https://lore.kernel.org/linux-trace-kernel/202401291043.e62e89dc-oliver.sang@intel.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240131185513.124644253@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: c1504e5102 ("eventfs: Implement eventfs dir creation functions")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 49304c2b93 upstream.
The dentry lookup for eventfs files was very broken, and had lots of
signs of the old situation where the filesystem names were all created
statically in the dentry tree, rather than being looked up dynamically
based on the eventfs data structures.
You could see it in the naming - how it claimed to "create" dentries
rather than just look up the dentries that were given it.
You could see it in various nonsensical and very incorrect operations,
like using "simple_lookup()" on the dentries that were passed in, which
only results in those dentries becoming negative dentries. Which meant
that any other lookup would possibly return ENOENT if it saw that
negative dentry before the data was then later filled in.
You could see it in the immense amount of nonsensical code that didn't
actually just do lookups.
Link: https://lore.kernel.org/linux-trace-kernel/202401291043.e62e89dc-oliver.sang@intel.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240131233227.73db55e1@gandalf.local.home
Cc: stable@vger.kernel.org
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Fixes: c1504e5102 ("eventfs: Implement eventfs dir creation functions")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 99c001cb61 upstream.
The eventfs_find_events() code tries to walk up the tree to find the
event directory that a dentry belongs to, in order to then find the
eventfs inode that is associated with that event directory.
However, it uses an odd combination of walking the dentry parent,
looking up the eventfs inode associated with that, and then looking up
the dentry from there. Repeat.
But the code shouldn't have back-pointers to dentries in the first
place, and it should just walk the dentry parenthood chain directly.
Similarly, 'set_top_events_ownership()' looks up the dentry from the
eventfs inode, but the only reason it wants a dentry is to look up the
superblock in order to look up the root dentry.
But it already has the real filesystem inode, which has that same
superblock pointer. So just pass in the superblock pointer using the
information that's already there, instead of looking up extraneous data
that is irrelevant.
Link: https://lore.kernel.org/linux-trace-kernel/202401291043.e62e89dc-oliver.sang@intel.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240131185512.638645365@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: c1504e5102 ("eventfs: Implement eventfs dir creation functions")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4fa4b010b8 upstream.
The tracefs-specific fields in the inode were not initialized before the
inode was exposed to others through the dentry with 'd_instantiate()'.
Move the field initializations up to before the d_instantiate.
Link: https://lore.kernel.org/linux-trace-kernel/20240131185512.478449628@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202401291043.e62e89dc-oliver.sang@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d81786f53a upstream.
eventfs uses the tracefs_inode and assumes that it's already initialized
to zero. That is, it doesn't set fields to zero (like ti->private) after
getting its tracefs_inode. This causes bugs due to stale values.
Just initialize the entire structure to zero on allocation so there isn't
any more surprises.
This is a partial fix to access to ti->private. The assignment still needs
to be made before the dentry is instantiated.
Link: https://lore.kernel.org/linux-trace-kernel/20240131185512.315825944@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202401291043.e62e89dc-oliver.sang@intel.com
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 29142dc92c upstream.
The 'eventfs_update_gid()' function is no longer called, so remove it
(and the helper function it uses).
Link: https://lore.kernel.org/all/CAHk-=wj+DsZZ=2iTUkJ-Nojs9fjYMvPs1NuoM3yK7aTDtJfPYQ@mail.gmail.com/
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 834bf76add upstream.
The eventfs inodes and directories are allocated when referenced. But this
leaves the issue of keeping consistent inode numbers and the number is
only saved in the inode structure itself. When the inode is no longer
referenced, it can be freed. When the file that the inode was representing
is referenced again, the inode is once again created, but the inode number
needs to be the same as it was before.
Just making the inode numbers the same for all files is fine, but that
does not work with directories. The find command will check for loops via
the inode number and having the same inode number for directories triggers:
# find /sys/kernel/tracing
find: File system loop detected;
'/sys/kernel/debug/tracing/events/initcall/initcall_finish' is part of the same file system loop as
'/sys/kernel/debug/tracing/events/initcall'.
[..]
Linus pointed out that the eventfs_inode structure ends with a single
32bit int, and on 64 bit machines, there's likely a 4 byte hole due to
alignment. We can use this hole to store the inode number for the
eventfs_inode. All directories in eventfs are represented by an
eventfs_inode and that data structure can hold its inode number.
That last int was also purposely placed at the end of the structure to
prevent holes from within. Now that there's a 4 byte number to hold the
inode, both the inode number and the last integer can be moved up in the
structure for better cache locality, where the llist and rcu fields can be
moved to the end as they are only used when the eventfs_inode is being
deleted.
Link: https://lore.kernel.org/all/CAMuHMdXKiorg-jiuKoZpfZyDJ3Ynrfb8=X+c7x0Eewxn-YRdCA@mail.gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240122152748.46897388@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Fixes: 53c41052ba ("eventfs: Have the inodes all for files and directories all be the same")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1057066009 upstream.
As noted in the "Deprecated Interfaces, Language Features, Attributes,
and Conventions" documentation [1], size calculations (especially
multiplication) should not be performed in memory allocator (or similar)
function arguments due to the risk of them overflowing. This could lead
to values wrapping around and a smaller allocation being made than the
caller was expecting. Using those allocations could lead to linear
overflows of heap memory and other misbehaviors.
So, use the purpose specific kcalloc() function instead of the argument
size * count in the kzalloc() function.
[1] https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments
Link: https://lore.kernel.org/linux-trace-kernel/20240115181658.4562-1-erick.archer@gmx.com
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://github.com/KSPP/linux/issues/162
Signed-off-by: Erick Archer <erick.archer@gmx.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 852e46e239 upstream.
The original eventfs code added a wrapper around the dcache_readdir open
callback and created all the dentries and inodes at open, and increment
their ref count. A wrapper was added around the dcache_readdir release
function to decrement all the ref counts of those created inodes and
dentries. But this proved to be buggy[1] for when a kprobe was created
during a dir read, it would create a dentry between the open and the
release, and because the release would decrement all ref counts of all
files and directories, that would include the kprobe directory that was
not there to have its ref count incremented in open. This would cause the
ref count to go to negative and later crash the kernel.
To solve this, the dentries and inodes that were created and had their ref
count upped in open needed to be saved. That list needed to be passed from
the open to the release, so that the release would only decrement the ref
counts of the entries that were incremented in the open.
Unfortunately, the dcache_readdir logic was already using the
file->private_data, which is the only field that can be used to pass
information from the open to the release. What was done was the eventfs
created another descriptor that had a void pointer to save the
dcache_readdir pointer, and it wrapped all the callbacks, so that it could
save the list of entries that had their ref counts incremented in the
open, and pass it to the release. The wrapped callbacks would just put
back the dcache_readdir pointer and call the functions it used so it could
still use its data[2].
But Linus had an issue with the "hijacking" of the file->private_data
(unfortunately this discussion was on a security list, so no public link).
Which we finally agreed on doing everything within the iterate_shared
callback and leave the dcache_readdir out of it[3]. All the information
needed for the getents() could be created then.
But this ended up being buggy too[4]. The iterate_shared callback was not
the right place to create the dentries and inodes. Even Christian Brauner
had issues with that[5].
An attempt was to go back to creating the inodes and dentries at
the open, create an array to store the information in the
file->private_data, and pass that information to the other callbacks.[6]
The difference between that and the original method, is that it does not
use dcache_readdir. It also does not up the ref counts of the dentries and
pass them. Instead, it creates an array of a structure that saves the
dentry's name and inode number. That information is used in the
iterate_shared callback, and the array is freed in the dir release. The
dentries and inodes created in the open are not used for the iterate_share
or release callbacks. Just their names and inode numbers.
Linus did not like that either[7] and just wanted to remove the dentries
being created in iterate_shared and use the hard coded inode numbers.
[ All this while Linus enjoyed an unexpected vacation during the merge
window due to lack of power. ]
[1] https://lore.kernel.org/linux-trace-kernel/20230919211804.230edf1e@gandalf.local.home/
[2] https://lore.kernel.org/linux-trace-kernel/20230922163446.1431d4fa@gandalf.local.home/
[3] https://lore.kernel.org/linux-trace-kernel/20240104015435.682218477@goodmis.org/
[4] https://lore.kernel.org/all/202401152142.bfc28861-oliver.sang@intel.com/
[5] https://lore.kernel.org/all/20240111-unzahl-gefegt-433acb8a841d@brauner/
[6] https://lore.kernel.org/all/20240116114711.7e8637be@gandalf.local.home/
[7] https://lore.kernel.org/all/20240116170154.5bf0a250@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20240116211353.573784051@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Fixes: 493ec81a8f ("eventfs: Stop using dcache_readdir() for getdents()")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202401152142.bfc28861-oliver.sang@intel.com
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 53c41052ba upstream.
The dentries and inodes are created in the readdir for the sole purpose of
getting a consistent inode number. Linus stated that is unnecessary, and
that all inodes can have the same inode number. For a virtual file system
they are pretty meaningless.
Instead use a single unique inode number for all files and one for all
directories.
Link: https://lore.kernel.org/all/20240116133753.2808d45e@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20240116211353.412180363@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ajay Kaher <ajay.kaher@broadcom.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1de94b52d5 upstream.
As the ei->entries array is fixed for the duration of the eventfs_inode,
it can be used to skip over already read entries in eventfs_iterate().
That is, if ctx->pos is greater than zero, there's no reason in doing the
loop across the ei->entries array for the entries less than ctx->pos.
Instead, start the lookup of the entries at the current ctx->pos.
Link: https://lore.kernel.org/all/CAHk-=wiKwDUDv3+jCsv-uacDcHDVTYsXtBR9=6sGM5mqX+DhOg@mail.gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240104220048.494956957@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 704f960dbe upstream.
In order to apply a shortcut to skip over the current ctx->pos
immediately, by using the ei->entries array, the reading of that array
should be first. Moving the array reading before the linked list reading
will make the shortcut change diff nicer to read.
Link: https://lore.kernel.org/all/CAHk-=wiKwDUDv3+jCsv-uacDcHDVTYsXtBR9=6sGM5mqX+DhOg@mail.gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240104220048.333115095@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1e4624eb5a upstream.
The ctx->pos was only updated when it added an entry, but the "skip to
current pos" check (c--) happened for every loop regardless of if the
entry was added or not. This inconsistency caused readdir to be incorrect.
It was due to:
for (i = 0; i < ei->nr_entries; i++) {
if (c > 0) {
c--;
continue;
}
mutex_lock(&eventfs_mutex);
/* If ei->is_freed then just bail here, nothing more to do */
if (ei->is_freed) {
mutex_unlock(&eventfs_mutex);
goto out;
}
r = entry->callback(name, &mode, &cdata, &fops);
mutex_unlock(&eventfs_mutex);
[..]
ctx->pos++;
}
But this can cause the iterator to return a file that was already read.
That's because of the way the callback() works. Some events may not have
all files, and the callback can return 0 to tell eventfs to skip the file
for this directory.
for instance, we have:
# ls /sys/kernel/tracing/events/ftrace/function
format hist hist_debug id inject
and
# ls /sys/kernel/tracing/events/sched/sched_switch/
enable filter format hist hist_debug id inject trigger
Where the function directory is missing "enable", "filter" and
"trigger". That's because the callback() for events has:
static int event_callback(const char *name, umode_t *mode, void **data,
const struct file_operations **fops)
{
struct trace_event_file *file = *data;
struct trace_event_call *call = file->event_call;
[..]
/*
* Only event directories that can be enabled should have
* triggers or filters, with the exception of the "print"
* event that can have a "trigger" file.
*/
if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) {
if (call->class->reg && strcmp(name, "enable") == 0) {
*mode = TRACE_MODE_WRITE;
*fops = &ftrace_enable_fops;
return 1;
}
if (strcmp(name, "filter") == 0) {
*mode = TRACE_MODE_WRITE;
*fops = &ftrace_event_filter_fops;
return 1;
}
}
if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) ||
strcmp(trace_event_name(call), "print") == 0) {
if (strcmp(name, "trigger") == 0) {
*mode = TRACE_MODE_WRITE;
*fops = &event_trigger_fops;
return 1;
}
}
[..]
return 0;
}
Where the function event has the TRACE_EVENT_FL_IGNORE_ENABLE set.
This means that the entries array elements for "enable", "filter" and
"trigger" when called on the function event will have the callback return
0 and not 1, to tell eventfs to skip these files for it.
Because the "skip to current ctx->pos" check happened for all entries, but
the ctx->pos++ only happened to entries that exist, it would confuse the
reading of a directory. Which would cause:
# ls /sys/kernel/tracing/events/ftrace/function/
format hist hist hist_debug hist_debug id inject inject
The missing "enable", "filter" and "trigger" caused ls to show "hist",
"hist_debug" and "inject" twice.
Update the ctx->pos for every iteration to keep its update and the "skip"
update consistent. This also means that on error, the ctx->pos needs to be
decremented if it was incremented without adding something.
Link: https://lore.kernel.org/all/20240104150500.38b15a62@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20240104220048.172295263@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: 493ec81a8f ("eventfs: Stop using dcache_readdir() for getdents()")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e109deadb7 upstream.
If ei->is_freed is set in eventfs_iterate(), it means that the directory
that is being iterated on is in the process of being freed. Just exit the
loop immediately when that is ever detected, and separate out the return
of the entry->callback() from ei->is_freed.
Link: https://lore.kernel.org/linux-trace-kernel/20240104220048.016261289@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8186fff7ab upstream.
Instead of walking the dentries on mount/remount to update the gid values of
all the dentries if a gid option is specified on mount, just update the root
inode. Add .getattr, .setattr, and .permissions on the tracefs inode
operations to update the permissions of the files and directories.
For all files and directories in the top level instance:
/sys/kernel/tracing/*
It will use the root inode as the default permissions. The inode that
represents: /sys/kernel/tracing (or wherever it is mounted).
When an instance is created:
mkdir /sys/kernel/tracing/instance/foo
The directory "foo" and all its files and directories underneath will use
the default of what foo is when it was created. A remount of tracefs will
not affect it.
If a user were to modify the permissions of any file or directory in
tracefs, it will also no longer be modified by a change in ownership of a
remount.
The events directory, if it is in the top level instance, will use the
tracefs root inode as the default ownership for itself and all the files and
directories below it.
For the events directory in an instance ("foo"), it will keep the ownership
of what it was when it was created, and that will be used as the default
ownership for the files and directories beneath it.
Link: https://lore.kernel.org/linux-trace-kernel/CAHk-=wjVdGkjDXBbvLn2wbZnqP4UsH46E3gqJ9m7UG6DpX2+WA@mail.gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240103215016.1e0c9811@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 493ec81a8f upstream.
The eventfs creates dynamically allocated dentries and inodes. Using the
dcache_readdir() logic for its own directory lookups requires hiding the
cursor of the dcache logic and playing games to allow the dcache_readdir()
to still have access to the cursor while the eventfs saved what it created
and what it needs to release.
Instead, just have eventfs have its own iterate_shared callback function
that will fill in the dent entries. This simplifies the code quite a bit.
Link: https://lore.kernel.org/linux-trace-kernel/20240104015435.682218477@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ajay Kaher <akaher@vmware.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b0f7e2d739 upstream.
The "lookup" parameter is a way to differentiate the call to
create_file/dir_dentry() from when it's just a lookup (no need to up the
dentry refcount) and accessed via a readdir (need to up the refcount).
But reality, it just makes the code more complex. Just up the refcount and
let the caller decide to dput() the result or not.
Link: https://lore.kernel.org/linux-trace-kernel/20240103102553.17a19cea@gandalf.local.home
Link: https://lore.kernel.org/linux-trace-kernel/20240104015435.517502710@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ajay Kaher <akaher@vmware.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fd56cd5f6d upstream.
A flag was needed to denote which eventfs_inode was the "events"
directory, so a bit was taken from the "nr_entries" field, as there's not
that many entries, and 2^30 is plenty. But the bit number for nr_entries
was not updated to reflect the bit taken from it, which would add an
unnecessary integer to the structure.
Link: https://lore.kernel.org/linux-trace-kernel/20240102151832.7ca87275@gandalf.local.home
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 7e8358edf5 ("eventfs: Fix file and directory uid and gid ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ad57986463 upstream.
If a getdents() is called on the tracefs directory but does not get all
the files, it can leave a "cursor" dentry in the d_subdirs list of tracefs
dentry. This cursor dentry does not have a d_inode for it. Before
referencing tracefs_inode from the dentry, the d_inode must first be
checked if it has content. If not, then it's not a tracefs_inode and can
be ignored.
The following caused a crash:
#define getdents64(fd, dirp, count) syscall(SYS_getdents64, fd, dirp, count)
#define BUF_SIZE 256
#define TDIR "/tmp/file0"
int main(void)
{
char buf[BUF_SIZE];
int fd;
int n;
mkdir(TDIR, 0777);
mount(NULL, TDIR, "tracefs", 0, NULL);
fd = openat(AT_FDCWD, TDIR, O_RDONLY);
n = getdents64(fd, buf, BUF_SIZE);
ret = mount(NULL, TDIR, NULL, MS_NOSUID|MS_REMOUNT|MS_RELATIME|MS_LAZYTIME,
"gid=1000");
return 0;
}
That's because the 256 BUF_SIZE was not big enough to read all the
dentries of the tracefs file system and it left a "cursor" dentry in the
subdirs of the tracefs root inode. Then on remounting with "gid=1000",
it would cause an iteration of all dentries which hit:
ti = get_tracefs(dentry->d_inode);
if (ti && (ti->flags & TRACEFS_EVENT_INODE))
eventfs_update_gid(dentry, gid);
Which crashed because of the dereference of the cursor dentry which had a NULL
d_inode.
In the subdir loop of the dentry lookup of set_gid(), if a child has a
NULL d_inode, simply skip it.
Link: https://lore.kernel.org/all/20240102135637.3a21fb10@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20240102151249.05da244d@gandalf.local.home
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 7e8358edf5 ("eventfs: Fix file and directory uid and gid ownership")
Reported-by: "Ubisectech Sirius" <bugreport@ubisectech.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7e8358edf5 upstream.
It was reported that when mounting the tracefs file system with a gid
other than root, the ownership did not carry down to the eventfs directory
due to the dynamic nature of it.
A fix was done to solve this, but it had two issues.
(a) if the attr passed into update_inode_attr() was NULL, it didn't do
anything. This is true for files that have not had a chown or chgrp
done to itself or any of its sibling files, as the attr is allocated
for all children when any one needs it.
# umount /sys/kernel/tracing
# mount -o rw,seclabel,relatime,gid=1000 -t tracefs nodev /mnt
# ls -ld /mnt/events/sched
drwxr-xr-x 28 root rostedt 0 Dec 21 13:12 /mnt/events/sched/
# ls -ld /mnt/events/sched/sched_switch
drwxr-xr-x 2 root rostedt 0 Dec 21 13:12 /mnt/events/sched/sched_switch/
But when checking the files:
# ls -l /mnt/events/sched/sched_switch
total 0
-rw-r----- 1 root root 0 Dec 21 13:12 enable
-rw-r----- 1 root root 0 Dec 21 13:12 filter
-r--r----- 1 root root 0 Dec 21 13:12 format
-r--r----- 1 root root 0 Dec 21 13:12 hist
-r--r----- 1 root root 0 Dec 21 13:12 id
-rw-r----- 1 root root 0 Dec 21 13:12 trigger
(b) When the attr does not denote the UID or GID, it defaulted to using
the parent uid or gid. This is incorrect as changing the parent
uid or gid will automatically change all its children.
# chgrp tracing /mnt/events/timer
# ls -ld /mnt/events/timer
drwxr-xr-x 2 root tracing 0 Dec 21 14:34 /mnt/events/timer
# ls -l /mnt/events/timer
total 0
-rw-r----- 1 root root 0 Dec 21 14:35 enable
-rw-r----- 1 root root 0 Dec 21 14:35 filter
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 hrtimer_cancel
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 hrtimer_expire_entry
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 hrtimer_expire_exit
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 hrtimer_init
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 hrtimer_start
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 itimer_expire
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 itimer_state
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 tick_stop
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 timer_cancel
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 timer_expire_entry
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 timer_expire_exit
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 timer_init
drwxr-xr-x 2 root tracing 0 Dec 21 14:35 timer_start
At first it was thought that this could be easily fixed by just making the
default ownership of the superblock when it was mounted. But this does not
handle the case of:
# chgrp tracing instances
# mkdir instances/foo
If the superblock was used, then the group ownership would be that of what
it was when it was mounted, when it should instead be "tracing".
Instead, set a flag for the top level eventfs directory ("events") to flag
which eventfs_inode belongs to it.
Since the "events" directory's dentry and inode are never freed, it does
not need to use its attr field to restore its mode and ownership. Use the
this eventfs_inode's attr as the default ownership for all the files and
directories underneath it.
When the events eventfs_inode is created, it sets its ownership to its
parent uid and gid. As the events directory is created at boot up before
it gets mounted, this will always be uid=0 and gid=0. If it's created via
an instance, then it will take the ownership of the instance directory.
When the file system is mounted, it will update all the gids if one is
specified. This will have a callback to update the events evenfs_inode's
default entries.
When a file or directory is created under the events directory, it will
walk the ei->dentry parents until it finds the evenfs_inode that belongs
to the events directory to retrieve the default uid and gid values.
Link: https://lore.kernel.org/all/CAHk-=wiwQtUHvzwyZucDq8=Gtw+AnwScyLhpFswrQ84PjhoGsg@mail.gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20231221190757.7eddbca9@gandalf.local.home
Cc: stable@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Dongliang Cui <cuidongliang390@gmail.com>
Cc: Hongyu Jin <hongyu.jin@unisoc.com>
Fixes: 0dfc852b6f ("eventfs: Have event files and directories default to parent uid and gid")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0dfc852b6f upstream.
Dongliang reported:
I found that in the latest version, the nodes of tracefs have been
changed to dynamically created.
This has caused me to encounter a problem where the gid I specified in
the mounting parameters cannot apply to all files, as in the following
situation:
/data/tmp/events # mount | grep tracefs
tracefs on /data/tmp type tracefs (rw,seclabel,relatime,gid=3012)
gid 3012 = readtracefs
/data/tmp # ls -lh
total 0
-r--r----- 1 root readtracefs 0 1970-01-01 08:00 README
-r--r----- 1 root readtracefs 0 1970-01-01 08:00 available_events
ums9621_1h10:/data/tmp/events # ls -lh
total 0
drwxr-xr-x 2 root root 0 2023-12-19 00:56 alarmtimer
drwxr-xr-x 2 root root 0 2023-12-19 00:56 asoc
It will prevent certain applications from accessing tracefs properly, I
try to avoid this issue by making the following modifications.
To fix this, have the files created default to taking the ownership of
the parent dentry unless the ownership was previously set by the user.
Link: https://lore.kernel.org/linux-trace-kernel/1703063706-30539-1-git-send-email-dongliang.cui@unisoc.com/
Link: https://lore.kernel.org/linux-trace-kernel/20231220105017.1489d790@gandalf.local.home
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Hongyu Jin <hongyu.jin@unisoc.com>
Fixes: 28e12c09f5 ("eventfs: Save ownership and mode")
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reported-by: Dongliang Cui <cuidongliang390@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5eaf7f0589 upstream.
Eventfs uses simple_lookup(), however, it will fail if the name of the
entry is beyond NAME_MAX length. When this error is encountered, eventfs
still tries to create dentries instead of skipping the dentry creation.
When the dentry is attempted to be created in this state d_wait_lookup()
will loop forever, waiting for the lookup to be removed.
Fix eventfs to return the error in simple_lookup() back to the caller
instead of continuing to try to create the dentry.
Link: https://lore.kernel.org/linux-trace-kernel/20231210213534.497-1-beaub@linux.microsoft.com
Fixes: 6394044955 ("eventfs: Implement eventfs lookup, read, open functions")
Link: https://lore.kernel.org/linux-trace-kernel/20231208183601.GA46-beaub@linux.microsoft.com/
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f49f950c21 upstream.
Since the locking of the parent->d_inode has been moved outside the
creation of the files and directories (as it use to be locked via a
conditional), add a WARN_ON_ONCE() to the case that it's not locked.
Link: https://lkml.kernel.org/r/20231121231112.853962542@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fc4561226f upstream.
The eventfs directory is dynamically created via the meta data supplied by
the existing trace events. All files and directories in eventfs has a
parent. Do not allow NULL to be passed into eventfs_start_creating() as
the parent because that should never happen. Warn if it does.
Link: https://lkml.kernel.org/r/20231121231112.693841807@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bcae32c563 upstream.
The both create_file_dentry() and create_dir_dentry() takes a boolean
parameter "lookup", as on lookup the inode_lock should already be taken,
but for dcache_dir_open_wrapper() it is not taken.
There's no reason that the dcache_dir_open_wrapper() can't take the
inode_lock before calling these functions. In fact, it's better if it
does, as the lock can be held throughout both directory and file
creations.
This also simplifies the code, and possibly prevents unexpected race
conditions when the lock is released.
Link: https://lkml.kernel.org/r/20231121231112.528544825@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4763d635c9 upstream.
If memory reclaim happens, it can reclaim file system pages. The file
system pages from eventfs may take the eventfs_mutex on reclaim. This
means that allocation while holding the eventfs_mutex must not call into
filesystem reclaim. A lockdep splat uncovered this.
Link: https://lkml.kernel.org/r/20231121231112.373501894@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 28e12c09f5 ("eventfs: Save ownership and mode")
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 71cade82f2 upstream.
With the call to simple_recursive_removal() on the entire eventfs sub
system when the directory is removed, it performs the d_invalidate on all
the dentries when it is removed. There's no need to do clean ups when a
dentry is being created while the directory is being deleted.
As dentries are cleaned up by the simpler_recursive_removal(), trying to
do d_invalidate() in these functions will cause the dentry to be
invalidated twice, and crash the kernel.
Link: https://lore.kernel.org/all/20231116123016.140576-1-naresh.kamboju@linaro.org/
Link: https://lkml.kernel.org/r/20231120235154.422970988@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 407c6726ca ("eventfs: Use simple_recursive_removal() to clean up dentries")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 88903daeca upstream.
The logic to free the eventfs_inode (ei) use to set is_freed and clear the
"dentry" field under the eventfs_mutex. But that changed when a race was
found where the ei->dentry needed to be cleared when the last dput() was
called on it. But there was still logic that checked if ei->dentry was not
NULL and is_freed is set, and would warn if it was.
But since that situation was changed and the ei->dentry isn't cleared
until the last dput() is called on it while the ei->is_freed is set, do
not test for that condition anymore, and change the comments to reflect
that.
Link: https://lkml.kernel.org/r/20231120235154.265826243@goodmis.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 020010fbfa ("eventfs: Delete eventfs_inode when the last dentry is freed")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 407c6726ca upstream.
Looking at how dentry is removed via the tracefs system, I found that
eventfs does not do everything that it did under tracefs. The tracefs
removal of a dentry calls simple_recursive_removal() that does a lot more
than a simple d_invalidate().
As it should be a requirement that any eventfs_inode that has a dentry, so
does its parent. When removing a eventfs_inode, if it has a dentry, a call
to simple_recursive_removal() on that dentry should clean up all the
dentries underneath it.
Add WARN_ON_ONCE() to check for the parent having a dentry if any children
do.
Link: https://lore.kernel.org/all/20231101022553.GE1957730@ZenIV/
Link: https://lkml.kernel.org/r/20231101172650.552471568@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Fixes: 5bdcd5f533 ("eventfs: Implement removal of meta data from eventfs")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 62d65cac11 upstream.
The top level events directory is no longer special with regards to how it
should be delete. Remove the extra processing for it in
eventfs_set_ei_status_free().
Link: https://lkml.kernel.org/r/20231101172650.340876747@goodmis.org
Cc: Ajay Kaher <akaher@vmware.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 020010fbfa upstream.
There exists a race between holding a reference of an eventfs_inode dentry
and the freeing of the eventfs_inode. If user space has a dentry held long
enough, it may still be able to access the dentry's eventfs_inode after it
has been freed.
To prevent this, have he eventfs_inode freed via the last dput() (or via
RCU if the eventfs_inode does not have a dentry).
This means reintroducing the eventfs_inode del_list field at a temporary
place to put the eventfs_inode. It needs to mark it as freed (via the
list) but also must invalidate the dentry immediately as the return from
eventfs_remove_dir() expects that they are. But the dentry invalidation
must not be called under the eventfs_mutex, so it must be done after the
eventfs_inode is marked as free (put on a deletion list).
Link: https://lkml.kernel.org/r/20231101172650.123479767@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ajay Kaher <akaher@vmware.com>
Fixes: 5bdcd5f533 ("eventfs: Implement removal of meta data from eventfs")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 44365329f8 upstream.
The callback function that is used to create inodes and dentries is not
protected by anything and the data that is passed to it could become
stale. After eventfs_remove_dir() is called by the tracing system, it is
free to remove the events that are associated to that directory.
Unfortunately, that means the callbacks must not be called after that.
CPU0 CPU1
---- ----
eventfs_root_lookup() {
eventfs_remove_dir() {
mutex_lock(&event_mutex);
ei->is_freed = set;
mutex_unlock(&event_mutex);
}
kfree(event_call);
for (...) {
entry = &ei->entries[i];
r = entry->callback() {
call = data; // call == event_call above
if (call->flags ...)
[ USE AFTER FREE BUG ]
The safest way to protect this is to wrap the callback with:
mutex_lock(&eventfs_mutex);
if (!ei->is_freed)
r = entry->callback();
else
r = -1;
mutex_unlock(&eventfs_mutex);
This will make sure that the callback will not be called after it is
freed. But now it needs to be known that the callback is called while
holding internal eventfs locks, and that it must not call back into the
eventfs / tracefs system. There's no reason it should anyway, but document
that as well.
Link: https://lore.kernel.org/all/CA+G9fYu9GOEbD=rR5eMR-=HJ8H6rMsbzDC2ZY5=Y50WpWAE7_Q@mail.gmail.com/
Link: https://lkml.kernel.org/r/20231101172649.906696613@goodmis.org
Cc: Ajay Kaher <akaher@vmware.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 28e12c09f5 upstream.
Now that inodes and dentries are created on the fly, they are also
reclaimed on memory pressure. Since the ownership and file mode are saved
in the inode, if they are freed, any changes to the ownership and mode
will be lost.
To counter this, if the user changes the permissions or ownership, save
them, and when creating the inodes again, restore those changes.
Link: https://lkml.kernel.org/r/20231101172649.691841445@goodmis.org
Cc: stable@vger.kernel.org
Cc: Ajay Kaher <akaher@vmware.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 6394044955 ("eventfs: Implement eventfs lookup, read, open functions")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 77a06c33a2 upstream.
The eventfs_inode (ei) is protected by SRCU, but the ei->dentry is not. It
is protected by the eventfs_mutex. Anytime the eventfs_mutex is released,
and access to the ei->dentry needs to be done, it should first check if
ei->is_freed is set under the eventfs_mutex. If it is, then the ei->dentry
is invalid and must not be used. The ei->dentry must only be accessed
under the eventfs_mutex and after checking if ei->is_freed is set.
When the ei is being freed, it will (under the eventfs_mutex) set is_freed
and at the same time move the dentry to a free list to be cleared after
the eventfs_mutex is released. This means that any access to the
ei->dentry must check first if ei->is_freed is set, because if it is, then
the dentry is on its way to be freed.
Also add comments to describe this better.
Link: https://lore.kernel.org/all/CA+G9fYt6pY+tMZEOg=SoEywQOe19fGP3uR15SGowkdK+_X85Cg@mail.gmail.com/
Link: https://lore.kernel.org/all/CA+G9fYuDP3hVQ3t7FfrBAjd_WFVSurMgCepTxunSJf=MTe=6aA@mail.gmail.com/
Link: https://lkml.kernel.org/r/20231101172649.477608228@goodmis.org
Cc: Ajay Kaher <akaher@vmware.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: Beau Belgrave <beaub@linux.microsoft.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Tested-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit db3a397209 upstream.
As the eventfs_inode is freed in two different locations, make a helper
function free_ei() to make sure all the allocated fields of the
eventfs_inode is freed.
This requires renaming the existing free_ei() which is called by the srcu
handler to free_rcu_ei() and have free_ei() just do the freeing, where
free_rcu_ei() will call it.
Link: https://lkml.kernel.org/r/20231101172649.265214087@goodmis.org
Cc: Ajay Kaher <akaher@vmware.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f2f496370a upstream.
The eventfs_inode->is_freed was a union with the rcu_head with the
assumption that when it was on the srcu list the head would contain a
pointer which would make "is_freed" true. But that was a wrong assumption
as the rcu head is a single link list where the last element is NULL.
Instead, split the nr_entries integer so that "is_freed" is one bit and
the nr_entries is the next 31 bits. As there shouldn't be more than 10
(currently there's at most 5 to 7 depending on the config), this should
not be a problem.
Link: https://lkml.kernel.org/r/20231101172649.049758712@goodmis.org
Cc: stable@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ajay Kaher <akaher@vmware.com>
Fixes: 6394044955 ("eventfs: Implement eventfs lookup, read, open functions")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 77bc4d4921 upstream.
The creation of the top events directory does a dget() at the end of the
creation in eventfs_create_events_dir() with a comment saying the final
dput() will happen when it is removed. The problem is that a dget() is
already done on the dentry when it was created with tracefs_start_creating()!
The dget() now just causes a memory leak of that dentry.
Remove the extra dget() as the final dput() in the deletion of the events
directory actually matches the one in tracefs_start_creating().
Link: https://lore.kernel.org/linux-trace-kernel/20231031124229.4f2e3fa1@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a9de4eb15a upstream.
As the comment right above a WARN_ON() in create_file_dentry() states:
* Note, with the mutex held, the e_dentry cannot have content
* and the ei->is_freed be true at the same time.
But the WARN_ON() only has:
WARN_ON_ONCE(ei->is_free);
Where to match the comment (and what it should actually do) is:
dentry = *e_dentry;
WARN_ON_ONCE(dentry && ei->is_free)
Also in that case, set dentry to NULL (although it should never happen).
Link: https://lore.kernel.org/linux-trace-kernel/20231024123628.62b88755@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b8a555dc31 upstream.
When building with clang and CONFIG_RANDSTRUCT_FULL=y, there is an error
due to a cast in eventfs_create_events_dir():
fs/tracefs/event_inode.c:734:10: error: casting from randomized structure pointer type 'struct dentry *' to 'struct eventfs_inode *'
734 | return (struct eventfs_inode *)dentry;
| ^
1 error generated.
Use the ERR_CAST() function to resolve the error, as it was designed for
this exact situation (casting an error pointer to another type).
Link: https://lore.kernel.org/linux-trace-kernel/20231018-ftrace-fix-clang-randstruct-v1-1-338cb214abfb@kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/1947
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2819f23ac1 upstream.
The update to removing the eventfs_file changed the way the events top
level directory was handled. Instead of returning a dentry, it now returns
the eventfs_inode. In this changed, the removing of the events top level
directory is not much different than removing any of the other
directories. Because of this, the removal just called eventfs_remove_dir()
instead of eventfs_remove_events_dir().
Although eventfs_remove_dir() does the clean up, it misses out on the
dget() of the ei->dentry done in eventfs_create_events_dir(). It makes
more sense to match eventfs_create_events_dir() with a specific function
eventfs_remove_events_dir() and this specific function can then perform
the dput() to the dentry that had the dget() when it was created.
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202310051743.y9EobbUr-lkp@intel.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5790b1fb3d upstream.
Instead of having a descriptor for every file represented in the eventfs
directory, only have the directory itself represented. Change the API to
send in a list of entries that represent all the files in the directory
(but not other directories). The entry list contains a name and a callback
function that will be used to create the files when they are accessed.
struct eventfs_inode *eventfs_create_events_dir(const char *name, struct dentry *parent,
const struct eventfs_entry *entries,
int size, void *data);
is used for the top level eventfs directory, and returns an eventfs_inode
that will be used by:
struct eventfs_inode *eventfs_create_dir(const char *name, struct eventfs_inode *parent,
const struct eventfs_entry *entries,
int size, void *data);
where both of the above take an array of struct eventfs_entry entries for
every file that is in the directory.
The entries are defined by:
typedef int (*eventfs_callback)(const char *name, umode_t *mode, void **data,
const struct file_operations **fops);
struct eventfs_entry {
const char *name;
eventfs_callback callback;
};
Where the name is the name of the file and the callback gets called when
the file is being created. The callback passes in the name (in case the
same callback is used for multiple files), a pointer to the mode, data and
fops. The data will be pointing to the data that was passed in
eventfs_create_dir() or eventfs_create_events_dir() but may be overridden
to point to something else, as it will be used to point to the
inode->i_private that is created. The information passed back from the
callback is used to create the dentry/inode.
If the callback fills the data and the file should be created, it must
return a positive number. On zero or negative, the file is ignored.
This logic may also be used as a prototype to convert entire pseudo file
systems into just-in-time allocation.
The "show_events_dentry" file has been updated to show the directories,
and any files they have.
With just the eventfs_file allocations:
Before after deltas for meminfo (in kB):
MemFree: -14360
MemAvailable: -14260
Buffers: 40
Cached: 24
Active: 44
Inactive: 48
Inactive(anon): 28
Active(file): 44
Inactive(file): 20
Dirty: -4
AnonPages: 28
Mapped: 4
KReclaimable: 132
Slab: 1604
SReclaimable: 132
SUnreclaim: 1472
Committed_AS: 12
Before after deltas for slabinfo:
<slab>: <objects> [ * <size> = <total>]
ext4_inode_cache 27 [* 1184 = 31968 ]
extent_status 102 [* 40 = 4080 ]
tracefs_inode_cache 144 [* 656 = 94464 ]
buffer_head 39 [* 104 = 4056 ]
shmem_inode_cache 49 [* 800 = 39200 ]
filp -53 [* 256 = -13568 ]
dentry 251 [* 192 = 48192 ]
lsm_file_cache 277 [* 32 = 8864 ]
vm_area_struct -14 [* 184 = -2576 ]
trace_event_file 1748 [* 88 = 153824 ]
kmalloc-1k 35 [* 1024 = 35840 ]
kmalloc-256 49 [* 256 = 12544 ]
kmalloc-192 -28 [* 192 = -5376 ]
kmalloc-128 -30 [* 128 = -3840 ]
kmalloc-96 10581 [* 96 = 1015776 ]
kmalloc-64 3056 [* 64 = 195584 ]
kmalloc-32 1291 [* 32 = 41312 ]
kmalloc-16 2310 [* 16 = 36960 ]
kmalloc-8 9216 [* 8 = 73728 ]
Free memory dropped by 14,360 kB
Available memory dropped by 14,260 kB
Total slab additions in size: 1,771,032 bytes
With this change:
Before after deltas for meminfo (in kB):
MemFree: -12084
MemAvailable: -11976
Buffers: 32
Cached: 32
Active: 72
Inactive: 168
Inactive(anon): 176
Active(file): 72
Inactive(file): -8
Dirty: 24
AnonPages: 196
Mapped: 8
KReclaimable: 148
Slab: 836
SReclaimable: 148
SUnreclaim: 688
Committed_AS: 324
Before after deltas for slabinfo:
<slab>: <objects> [ * <size> = <total>]
tracefs_inode_cache 144 [* 656 = 94464 ]
shmem_inode_cache -23 [* 800 = -18400 ]
filp -92 [* 256 = -23552 ]
dentry 179 [* 192 = 34368 ]
lsm_file_cache -3 [* 32 = -96 ]
vm_area_struct -13 [* 184 = -2392 ]
trace_event_file 1748 [* 88 = 153824 ]
kmalloc-1k -49 [* 1024 = -50176 ]
kmalloc-256 -27 [* 256 = -6912 ]
kmalloc-128 1864 [* 128 = 238592 ]
kmalloc-64 4685 [* 64 = 299840 ]
kmalloc-32 -72 [* 32 = -2304 ]
kmalloc-16 256 [* 16 = 4096 ]
total = 721352
Free memory dropped by 12,084 kB
Available memory dropped by 11,976 kB
Total slab additions in size: 721,352 bytes
That's over 2 MB in savings per instance for free and available memory,
and over 1 MB in savings per instance of slab memory.
Link: https://lore.kernel.org/linux-trace-kernel/20231003184059.4924468e@gandalf.local.home
Link: https://lore.kernel.org/linux-trace-kernel/20231004165007.43d79161@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ajay Kaher <akaher@vmware.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit fa18a8a053.
The eventfs was not designed properly and may have some hidden bugs in it.
Linus rewrote it properly and I trust his version more than this one. Revert
the backported patches for 6.6 and re-apply all the changes to make it
equivalent to Linus's version.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 9aaee3eebc.
The eventfs was not designed properly and may have some hidden bugs in it.
Linus rewrote it properly and I trust his version more than this one. Revert
the backported patches for 6.6 and re-apply all the changes to make it
equivalent to Linus's version.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit ea4c30a0a7.
The eventfs was not designed properly and may have some hidden bugs in it.
Linus rewrote it properly and I trust his version more than this one. Revert
the backported patches for 6.6 and re-apply all the changes to make it
equivalent to Linus's version.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 055907ad2c.
The eventfs was not designed properly and may have some hidden bugs in it.
Linus rewrote it properly and I trust his version more than this one. Revert
the backported patches for 6.6 and re-apply all the changes to make it
equivalent to Linus's version.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit d8f492a059.
The eventfs was not designed properly and may have some hidden bugs in it.
Linus rewrote it properly and I trust his version more than this one. Revert
the backported patches for 6.6 and re-apply all the changes to make it
equivalent to Linus's version.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 6abb8c223c.
The eventfs was not designed properly and may have some hidden bugs in it.
Linus rewrote it properly and I trust his version more than this one. Revert
the backported patches for 6.6 and re-apply all the changes to make it
equivalent to Linus's version.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 60f92acb60 upstream.
Patch series "fs/proc: do_task_stat: use sig->stats_".
do_task_stat() has the same problem as getrusage() had before "getrusage:
use sig->stats_lock rather than lock_task_sighand()": a hard lockup. If
NR_CPUS threads call lock_task_sighand() at the same time and the process
has NR_THREADS, spin_lock_irq will spin with irqs disabled O(NR_CPUS *
NR_THREADS) time.
This patch (of 3):
thread_group_cputime() does its own locking, we can safely shift
thread_group_cputime_adjusted() which does another for_each_thread loop
outside of ->siglock protected section.
Not only this removes for_each_thread() from the critical section with
irqs disabled, this removes another case when stats_lock is taken with
siglock held. We want to remove this dependency, then we can change the
users of stats_lock to not disable irqs.
Link: https://lkml.kernel.org/r/20240123153313.GA21832@redhat.com
Link: https://lkml.kernel.org/r/20240123153355.GA21854@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Dylan Hatch <dylanbhatch@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e656c7a9e5 upstream.
For shared memory of type SHM_HUGETLB, hugetlb pages are reserved in
shmget() call. If SHM_NORESERVE flags is specified then the hugetlb pages
are not reserved. However when the shared memory is attached with the
shmat() call the hugetlb pages are getting reserved incorrectly for
SHM_HUGETLB shared memory created with SHM_NORESERVE which is a bug.
-------------------------------
Following test shows the issue.
$cat shmhtb.c
int main()
{
int shmflags = 0660 | IPC_CREAT | SHM_HUGETLB | SHM_NORESERVE;
int shmid;
shmid = shmget(SKEY, SHMSZ, shmflags);
if (shmid < 0)
{
printf("shmat: shmget() failed, %d\n", errno);
return 1;
}
printf("After shmget()\n");
system("cat /proc/meminfo | grep -i hugepages_");
shmat(shmid, NULL, 0);
printf("\nAfter shmat()\n");
system("cat /proc/meminfo | grep -i hugepages_");
shmctl(shmid, IPC_RMID, NULL);
return 0;
}
#sysctl -w vm.nr_hugepages=20
#./shmhtb
After shmget()
HugePages_Total: 20
HugePages_Free: 20
HugePages_Rsvd: 0
HugePages_Surp: 0
After shmat()
HugePages_Total: 20
HugePages_Free: 20
HugePages_Rsvd: 5 <--
HugePages_Surp: 0
--------------------------------
Fix is to ensure that hugetlb pages are not reserved for SHM_HUGETLB shared
memory in the shmat() call.
Link: https://lkml.kernel.org/r/1706040282-12388-1-git-send-email-prakash.sangappa@oracle.com
Signed-off-by: Prakash Sangappa <prakash.sangappa@oracle.com>
Acked-by: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cda4672da1 upstream.
In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was
caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This
implies before the refcount could be increment here, it was freed.
In same file, in "handle_cap_grant()" refcount is decremented by this
line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race
occurred and resource was freed by the latter line before the former
line could increment it.
encode_cap_msg() is called by __send_cap() and __send_cap() is called by
ceph_check_caps() after calling __prep_cap(). __prep_cap() is where
arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where
the refcount must be increased to prevent "use after free" error.
Cc: stable@vger.kernel.org
Link: https://tracker.ceph.com/issues/59259
Signed-off-by: Rishabh Dave <ridave@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 46f5ab762d upstream.
When we added mount_setattr() I added additional checks compared to the
legacy do_reconfigure_mnt() and do_change_type() helpers used by regular
mount(2). If that mount had a parent then verify that the caller and the
mount namespace the mount is attached to match and if not make sure that
it's an anonymous mount.
The real rootfs falls into neither category. It is neither an anoymous
mount because it is obviously attached to the initial mount namespace
but it also obviously doesn't have a parent mount. So that means legacy
mount(2) allows changing mount properties on the real rootfs but
mount_setattr(2) blocks this. I never thought much about this but of
course someone on this planet of earth changes properties on the real
rootfs as can be seen in [1].
Since util-linux finally switched to the new mount api in 2.39 not so
long ago it also relies on mount_setattr() and that surfaced this issue
when Fedora 39 finally switched to it. Fix this.
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2256843
Link: https://lore.kernel.org/r/20240206-vfs-mount-rootfs-v1-1-19b335eee133@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Reported-by: Karel Zak <kzak@redhat.com>
Cc: stable@vger.kernel.org # v5.12+
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 14db5f64a9 upstream.
Write error handling is racy and can sometime lead to the error recovery
path wrongly changing the inode size of a sequential zone file to an
incorrect value which results in garbage data being readable at the end
of a file. There are 2 problems:
1) zonefs_file_dio_write() updates a zone file write pointer offset
after issuing a direct IO with iomap_dio_rw(). This update is done
only if the IO succeed for synchronous direct writes. However, for
asynchronous direct writes, the update is done without waiting for
the IO completion so that the next asynchronous IO can be
immediately issued. However, if an asynchronous IO completes with a
failure right before the i_truncate_mutex lock protecting the update,
the update may change the value of the inode write pointer offset
that was corrected by the error path (zonefs_io_error() function).
2) zonefs_io_error() is called when a read or write error occurs. This
function executes a report zone operation using the callback function
zonefs_io_error_cb(), which does all the error recovery handling
based on the current zone condition, write pointer position and
according to the mount options being used. However, depending on the
zoned device being used, a report zone callback may be executed in a
context that is different from the context of __zonefs_io_error(). As
a result, zonefs_io_error_cb() may be executed without the inode
truncate mutex lock held, which can lead to invalid error processing.
Fix both problems as follows:
- Problem 1: Perform the inode write pointer offset update before a
direct write is issued with iomap_dio_rw(). This is safe to do as
partial direct writes are not supported (IOMAP_DIO_PARTIAL is not
set) and any failed IO will trigger the execution of zonefs_io_error()
which will correct the inode write pointer offset to reflect the
current state of the one on the device.
- Problem 2: Change zonefs_io_error_cb() into zonefs_handle_io_error()
and call this function directly from __zonefs_io_error() after
obtaining the zone information using blkdev_report_zones() with a
simple callback function that copies to a local stack variable the
struct blk_zone obtained from the device. This ensures that error
handling is performed holding the inode truncate mutex.
This change also simplifies error handling for conventional zone files
by bypassing the execution of report zones entirely. This is safe to
do because the condition of conventional zones cannot be read-only or
offline and conventional zone files are always fully mapped with a
constant file size.
Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Fixes: 8dcc1a9d90 ("fs: New zonefs file system")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4860abb91f upstream.
The conversion to netfs in the 6.3 kernel caused a regression when
maximum write size is set by the server to an unexpected value which is
not a multiple of 4096 (similarly if the user overrides the maximum
write size by setting mount parm "wsize", but sets it to a value that
is not a multiple of 4096). When negotiated write size is not a
multiple of 4096 the netfs code can skip the end of the final
page when doing large sequential writes, causing data corruption.
This section of code is being rewritten/removed due to a large
netfs change, but until that point (ie for the 6.3 kernel until now)
we can not support non-standard maximum write sizes.
Add a warning if a user specifies a wsize on mount that is not
a multiple of 4096 (and round down), also add a change where we
round down the maximum write size if the server negotiates a value
that is not a multiple of 4096 (we also have to check to make sure that
we do not round it down to zero).
Reported-by: "R. Diez" <rdiez-2006@rd10.de>
Fixes: d08089f649 ("cifs: Change the I/O paths to use an iterator rather than a page list")
Suggested-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Acked-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Tested-by: Matthew Ruffell <matthew.ruffell@canonical.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: stable@vger.kernel.org # v6.3+
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4508ec1735 upstream.
When uid, gid and cruid are not specified, we need to dynamically
set them into the filesystem context used for automounting otherwise
they'll end up reusing the values from the parent mount.
Fixes: 9fd29a5bae ("cifs: use fs_context for automounts")
Reported-by: Shane Nehring <snehring@iastate.edu>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2259257
Cc: stable@vger.kernel.org # 6.2+
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 38296afe3c upstream.
Syzbot reported a hang issue in migrate_pages_batch() called by mbind()
and nilfs_lookup_dirty_data_buffers() called in the log writer of nilfs2.
While migrate_pages_batch() locks a folio and waits for the writeback to
complete, the log writer thread that should bring the writeback to
completion picks up the folio being written back in
nilfs_lookup_dirty_data_buffers() that it calls for subsequent log
creation and was trying to lock the folio. Thus causing a deadlock.
In the first place, it is unexpected that folios/pages in the middle of
writeback will be updated and become dirty. Nilfs2 adds a checksum to
verify the validity of the log being written and uses it for recovery at
mount, so data changes during writeback are suppressed. Since this is
broken, an unclean shutdown could potentially cause recovery to fail.
Investigation revealed that the root cause is that the wait for writeback
completion in nilfs_page_mkwrite() is conditional, and if the backing
device does not require stable writes, data may be modified without
waiting.
Fix these issues by making nilfs_page_mkwrite() wait for writeback to
finish regardless of the stable write requirement of the backing device.
Link: https://lkml.kernel.org/r/20240131145657.4209-1-konishi.ryusuke@gmail.com
Fixes: 1d1d1a7672 ("mm: only enforce stable page writes if the backing device requires it")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+ee2ae68da3b22d04cd8d@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/00000000000047d819061004ad6c@google.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 67b8bcbaed upstream.
The helper function nilfs_recovery_copy_block() of
nilfs_recovery_dsync_blocks(), which recovers data from logs created by
data sync writes during a mount after an unclean shutdown, incorrectly
calculates the on-page offset when copying repair data to the file's page
cache. In environments where the block size is smaller than the page
size, this flaw can cause data corruption and leak uninitialized memory
bytes during the recovery process.
Fix these issues by correcting this byte offset calculation on the page.
Link: https://lkml.kernel.org/r/20240124121936.10575-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 108a020c64 upstream.
ksmbd_iov_pin_rsp_read() doesn't free the provided aux buffer if it
fails. Seems to be the caller's responsibility to clear the buffer in
error case.
Found by Linux Verification Center (linuxtesting.org).
Fixes: e2b76ab8b5 ("ksmbd: add support for read compound")
Cc: stable@vger.kernel.org
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2331fd4a49 upstream.
After updating bb_free in mb_free_blocks, it is possible to return without
updating bb_fragments because the block being freed is found to have
already been freed, which leads to inconsistency between bb_free and
bb_fragments.
Since the group may be unlocked in ext4_grp_locked_error(), this can lead
to problems such as dividing by zero when calculating the average fragment
length. Hence move the update of bb_free to after the block double-free
check guarantees that the corresponding statistics are updated only after
the core block bitmap is modified.
Fixes: eabe0444df ("ext4: speed-up releasing blocks on commit")
CC: <stable@vger.kernel.org> # 3.10
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240104142040.2835097-5-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 55583e899a upstream.
In ext4_move_extents(), moved_len is only updated when all moves are
successfully executed, and only discards orig_inode and donor_inode
preallocations when moved_len is not zero. When the loop fails to exit
after successfully moving some extents, moved_len is not updated and
remains at 0, so it does not discard the preallocations.
If the moved extents overlap with the preallocated extents, the
overlapped extents are freed twice in ext4_mb_release_inode_pa() and
ext4_process_freed_data() (as described in commit 94d7c16cbb ("ext4:
Fix double-free of blocks with EXT4_IOC_MOVE_EXT")), and bb_free is
incremented twice. Hence when trim is executed, a zero-division bug is
triggered in mb_update_avg_fragment_size() because bb_free is not zero
and bb_fragments is zero.
Therefore, update move_len after each extent move to avoid the issue.
Reported-by: Wei Chen <harperchen1110@gmail.com>
Reported-by: xingwei lee <xrivendell7@gmail.com>
Closes: https://lore.kernel.org/r/CAO4mrferzqBUnCag8R3m2zf897ts9UEuhjFQGPtODT92rYyR2Q@mail.gmail.com
Fixes: fcf6b1b729 ("ext4: refactor ext4_move_extents code base")
CC: <stable@vger.kernel.org> # 3.18
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240104142040.2835097-2-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit cffe487026 ]
In this loop, we step through the buffer and after each item we check
if the size_left is greater than the minimum size we need. However,
the problem is that "bytes_left" is type ssize_t while sizeof() is type
size_t. That means that because of type promotion, the comparison is
done as an unsigned and if we have negative bytes left the loop
continues instead of ending.
Fixes: fe856be475 ("CIFS: parse and store info on iface queries")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 5571e41ec6 upstream.
While running the CI for an unrelated change I hit the following panic
with generic/648 on btrfs_holes_spacecache.
assertion failed: block_start != EXTENT_MAP_HOLE, in fs/btrfs/extent_io.c:1385
------------[ cut here ]------------
kernel BUG at fs/btrfs/extent_io.c:1385!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 2695096 Comm: fsstress Kdump: loaded Tainted: G W 6.8.0-rc2+ #1
RIP: 0010:__extent_writepage_io.constprop.0+0x4c1/0x5c0
Call Trace:
<TASK>
extent_write_cache_pages+0x2ac/0x8f0
extent_writepages+0x87/0x110
do_writepages+0xd5/0x1f0
filemap_fdatawrite_wbc+0x63/0x90
__filemap_fdatawrite_range+0x5c/0x80
btrfs_fdatawrite_range+0x1f/0x50
btrfs_write_out_cache+0x507/0x560
btrfs_write_dirty_block_groups+0x32a/0x420
commit_cowonly_roots+0x21b/0x290
btrfs_commit_transaction+0x813/0x1360
btrfs_sync_file+0x51a/0x640
__x64_sys_fdatasync+0x52/0x90
do_syscall_64+0x9c/0x190
entry_SYSCALL_64_after_hwframe+0x6e/0x76
This happens because we fail to write out the free space cache in one
instance, come back around and attempt to write it again. However on
the second pass through we go to call btrfs_get_extent() on the inode to
get the extent mapping. Because this is a new block group, and with the
free space inode we always search the commit root to avoid deadlocking
with the tree, we find nothing and return a EXTENT_MAP_HOLE for the
requested range.
This happens because the first time we try to write the space cache out
we hit an error, and on an error we drop the extent mapping. This is
normal for normal files, but the free space cache inode is special. We
always expect the extent map to be correct. Thus the second time
through we end up with a bogus extent map.
Since we're deprecating this feature, the most straightforward way to
fix this is to simply skip dropping the extent map range for this failed
range.
I shortened the test by using error injection to stress the area to make
it easier to reproduce. With this patch in place we no longer panic
with my error injection test.
CC: stable@vger.kernel.org # 4.14+
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>
commit 1bd96c92c6 upstream.
Currently we allow an encoded write against inodes that have the NODATASUM
flag set, either because they are NOCOW files or they were created while
the filesystem was mounted with "-o nodatasum". This results in having
compressed extents without corresponding checksums, which is a filesystem
inconsistency reported by 'btrfs check'.
For example, running btrfs/281 with MOUNT_OPTIONS="-o nodatacow" triggers
this and 'btrfs check' errors out with:
[1/7] checking root items
[2/7] checking extents
[3/7] checking free space tree
[4/7] checking fs roots
root 256 inode 257 errors 1040, bad file extent, some csum missing
root 256 inode 258 errors 1040, bad file extent, some csum missing
ERROR: errors found in fs roots
(...)
So reject encoded writes if the target inode has NODATASUM set.
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit feefe1f49d upstream.
Currently when doing a write to a file we always reserve metadata space
for inserting data checksums. However we don't need to do it if we have
a nodatacow file (-o nodatacow mount option or chattr +C) or if checksums
are disabled (-o nodatasum mount option), as in that case we are only
adding unnecessary pressure to metadata reservations.
For example on x86_64, with the default node size of 16K, a 4K buffered
write into a nodatacow file is reserving 655360 bytes of metadata space,
as it's accounting for checksums. After this change, which stops reserving
space for checksums if we have a nodatacow file or checksums are disabled,
we only need to reserve 393216 bytes of metadata.
CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f884a9f9e5 upstream.
When some ioctl flags are checked we return EOPNOTSUPP, like for
BTRFS_SCRUB_SUPPORTED_FLAGS, BTRFS_SUBVOL_CREATE_ARGS_MASK or fallocate
modes. The EINVAL is supposed to be for a supported but invalid
values or combination of options. Fix that when checking send flags so
it's consistent with the rest.
CC: stable@vger.kernel.org # 4.14+
Link: https://lore.kernel.org/linux-btrfs/CAL3q7H5rryOLzp3EKq8RTbjMHMHeaJubfpsVLF6H4qJnKCUR1w@mail.gmail.com/
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a8df356199 upstream.
If a subvolume still exists, forbid deleting its qgroup 0/subvolid.
This behavior generally leads to incorrect behavior in squotas and
doesn't have a legitimate purpose.
Fixes: cecbb533b5 ("btrfs: record simple quota deltas in delayed refs")
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
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 e03ee2fe87 upstream.
[BUG]
There is a syzbot crash, triggered by the ASSERT() during subvolume
creation:
assertion failed: !anon_dev, in fs/btrfs/disk-io.c:1319
------------[ cut here ]------------
kernel BUG at fs/btrfs/disk-io.c:1319!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
RIP: 0010:btrfs_get_root_ref.part.0+0x9aa/0xa60
<TASK>
btrfs_get_new_fs_root+0xd3/0xf0
create_subvol+0xd02/0x1650
btrfs_mksubvol+0xe95/0x12b0
__btrfs_ioctl_snap_create+0x2f9/0x4f0
btrfs_ioctl_snap_create+0x16b/0x200
btrfs_ioctl+0x35f0/0x5cf0
__x64_sys_ioctl+0x19d/0x210
do_syscall_64+0x3f/0xe0
entry_SYSCALL_64_after_hwframe+0x63/0x6b
---[ end trace 0000000000000000 ]---
[CAUSE]
During create_subvol(), after inserting root item for the newly created
subvolume, we would trigger btrfs_get_new_fs_root() to get the
btrfs_root of that subvolume.
The idea here is, we have preallocated an anonymous device number for
the subvolume, thus we can assign it to the new subvolume.
But there is really nothing preventing things like backref walk to read
the new subvolume.
If that happens before we call btrfs_get_new_fs_root(), the subvolume
would be read out, with a new anonymous device number assigned already.
In that case, we would trigger ASSERT(), as we really expect no one to
read out that subvolume (which is not yet accessible from the fs).
But things like backref walk is still possible to trigger the read on
the subvolume.
Thus our assumption on the ASSERT() is not correct in the first place.
[FIX]
Fix it by removing the ASSERT(), and just free the @anon_dev, reset it
to 0, and continue.
If the subvolume tree is read out by something else, it should have
already get a new anon_dev assigned thus we only need to free the
preallocated one.
Reported-by: Chenyuan Yang <chenyuan0y@gmail.com>
Fixes: 2dfb1e43f5 ("btrfs: preallocate anon block device at first phase of snapshot creation")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
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>
commit 0c309d66da upstream.
Creating a qgroup 0/subvolid leads to various races and it isn't
helpful, because you can't specify a subvol id when creating a subvol,
so you can't be sure it will be the right one. Any requirements on the
automatic subvol can be gratified by using a higher level qgroup and the
inheritance parameters of subvol creation.
Fixes: cecbb533b5 ("btrfs: record simple quota deltas in delayed refs")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
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 f4a9f21941 upstream.
Before deleting a block group that is in the list of unused block groups
(fs_info->unused_bgs), we check if the block group became used before
deleting it, as extents from it may have been allocated after it was added
to the list.
However even if the block group was not yet used, there may be tasks that
have only reserved space and have not yet allocated extents, and they
might be relying on the availability of the unused block group in order
to allocate extents. The reservation works first by increasing the
"bytes_may_use" field of the corresponding space_info object (which may
first require flushing delayed items, allocating a new block group, etc),
and only later a task does the actual allocation of extents.
For metadata we usually don't end up using all reserved space, as we are
pessimistic and typically account for the worst cases (need to COW every
single node in a path of a tree at maximum possible height, etc). For
data we usually reserve the exact amount of space we're going to allocate
later, except when using compression where we always reserve space based
on the uncompressed size, as compression is only triggered when writeback
starts so we don't know in advance how much space we'll actually need, or
if the data is compressible.
So don't delete an unused block group if the total size of its space_info
object minus the block group's size is less then the sum of used space and
space that may be used (space_info->bytes_may_use), as that means we have
tasks that reserved space and may need to allocate extents from the block
group. In this case, besides skipping the deletion, re-add the block group
to the list of unused block groups so that it may be reconsidered later,
in case the tasks that reserved space end up not needing to allocate
extents from it.
Allowing the deletion of the block group while we have reserved space, can
result in tasks failing to allocate metadata extents (-ENOSPC) while under
a transaction handle, resulting in a transaction abort, or failure during
writeback for the case of data extents.
CC: stable@vger.kernel.org # 6.0+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1693d5442c upstream.
Add a helper function to determine if a block group is being used and make
use of it at btrfs_delete_unused_bgs(). This helper will also be used in
future code changes.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b2dd7b953c ]
The issue here is when this is called from ntfs_load_attr_list(). The
"size" comes from le32_to_cpu(attr->res.data_size) so it can't overflow
on a 64bit systems but on 32bit systems the "+ 1023" can overflow and
the result is zero. This means that the kmalloc will succeed by
returning the ZERO_SIZE_PTR and then the memcpy() will crash with an
Oops on the next line.
Fixes: be71b5cba2 ("fs/ntfs3: Add attrib operations")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 9c04138414 upstream.
Update the per-folio stable writes flag dependening on which device an
inode resides on.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231025141020.192413-5-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit c421df0b19 upstream.
Introduce a local boolean variable if FS_XFLAG_REALTIME to make the
checks for it more obvious, and de-densify a few of the conditionals
using it to make them more readable while at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231025141020.192413-4-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 9c235dfc3d upstream.
When we're recovering ondisk quota records from the log, we need to
validate the recovered buffer contents before writing them to disk.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ed17f7da5f upstream.
Since the introduction of xfs_dqblk in V5, xfs really ought to find the
dqblk pointer from the dquot buffer, then compute the xfs_disk_dquot
pointer from the dqblk pointer. Fix the open-coded xfs_buf_offset calls
and do the type checking in the correct order.
Note that this has made no practical difference since the start of the
xfs_disk_dquot is coincident with the start of the xfs_dqblk.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 038ca189c0 upstream.
Discovered when trying to track down a weird recovery corruption
issue that wasn't detected at recovery time.
The specific corruption was a zero extent count field when big
extent counts are in use, and it turns out the dinode verifier
doesn't detect that specific corruption case, either. So fix it too.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit a2e4388adf upstream.
Commit 57c0f4a8ea attempted to fix the select in the kconfig entry
XFS_ONLINE_SCRUB_STATS by selecting XFS_DEBUG, but the original
intention was to select DEBUG_FS, since the feature relies on debugfs to
export the related scrub statistics.
Fixes: 57c0f4a8ea ("xfs: fix select in config XFS_ONLINE_SCRUB_STATS")
Reported-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f63a5b3769 upstream.
We've been seeing XFS errors like the following:
XFS: Internal error i != 1 at line 3526 of file fs/xfs/libxfs/xfs_btree.c. Caller xfs_btree_insert+0x1ec/0x280
...
Call Trace:
xfs_corruption_error+0x94/0xa0
xfs_btree_insert+0x221/0x280
xfs_alloc_fixup_trees+0x104/0x3e0
xfs_alloc_ag_vextent_size+0x667/0x820
xfs_alloc_fix_freelist+0x5d9/0x750
xfs_free_extent_fix_freelist+0x65/0xa0
__xfs_free_extent+0x57/0x180
...
This is the XFS_IS_CORRUPT() check in xfs_btree_insert() when
xfs_btree_insrec() fails.
After converting this into a panic and dissecting the core dump, I found
that xfs_btree_insrec() is failing because it's trying to split a leaf
node in the cntbt when the AG free list is empty. In particular, it's
failing to get a block from the AGFL _while trying to refill the AGFL_.
If a single operation splits every level of the bnobt and the cntbt (and
the rmapbt if it is enabled) at once, the free list will be empty. Then,
when the next operation tries to refill the free list, it allocates
space. If the allocation does not use a full extent, it will need to
insert records for the remaining space in the bnobt and cntbt. And if
those new records go in full leaves, the leaves (and potentially more
nodes up to the old root) need to be split.
Fix it by accounting for the additional splits that may be required to
refill the free list in the calculation for the minimum free list size.
P.S. As far as I can tell, this bug has existed for a long time -- maybe
back to xfs-history commit afdf80ae7405 ("Add XFS_AG_MAXLEVELS macros
...") in April 1994! It requires a very unlucky sequence of events, and
in fact we didn't hit it until a particular sparse mmap workload updated
from 5.12 to 5.19. But this bug existed in 5.12, so it must've been
exposed by some other change in allocation or writeback patterns. It's
also much less likely to be hit with the rmapbt enabled, since that
increases the minimum free list size and is unlikely to split at the
same time as the bnobt and cntbt.
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 471de20303 upstream.
We flush the data device cache before we issue external log IO. If
the flush fails, we shut down the log immediately and return. However,
the iclog->ic_sema is left in a decremented state so let's add an up().
Prior to this patch, xfs/438 would fail consistently when running with
an external log device:
sync
-> xfs_log_force
-> xlog_write_iclog
-> down(&iclog->ic_sema)
-> blkdev_issue_flush (fail causes us to intiate shutdown)
-> xlog_force_shutdown
-> return
unmount
-> xfs_log_umount
-> xlog_wait_iclog_completion
-> down(&iclog->ic_sema) --------> HANG
There is a second early return / shutdown. Make sure the up() happens
for it as well. Also make sure we cleanup the iclog state,
xlog_state_done_syncing, before dropping the iclog lock.
Fixes: b5d721eaae ("xfs: external logs need to flush data device")
Fixes: 842a42d126 ("xfs: shutdown on failure to add page to log bio")
Fixes: 7d839e325a ("xfs: check return codes when flushing block devices")
Signed-off-by: Leah Rumancik <leah.rumancik@gmail.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 55f669f341 upstream.
xfs_reflink_end_cow_extent looks up the COW extent and the data fork
extent at offset_fsb, and then proceeds to remap the common subset
between the two.
It does however not limit the remapped extent to the passed in
[*offset_fsbm end_fsb] range and thus potentially remaps more blocks than
the one handled by the current I/O completion. This means that with
sufficiently large data and COW extents we could be remapping COW fork
mappings that have not been written to, leading to a stale data exposure
on a powerfail event.
We use to have a xfs_trim_range to make the remap fit the I/O completion
range, but that got (apparently accidentally) removed in commit
df2fd88f8a ("xfs: rewrite xfs_reflink_end_cow to use intents").
Note that I've only found this by code inspection, and a test case would
probably require very specific delay and error injection.
Fixes: df2fd88f8a ("xfs: rewrite xfs_reflink_end_cow to use intents")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f8f9d952e4 upstream.
When recovering intents, we capture newly created intent items as part of
committing recovered intent items. If intent recovery fails at a later
point, we forget to remove those newly created intent items from the AIL
and hang:
[root@localhost ~]# cat /proc/539/stack
[<0>] xfs_ail_push_all_sync+0x174/0x230
[<0>] xfs_unmount_flush_inodes+0x8d/0xd0
[<0>] xfs_mountfs+0x15f7/0x1e70
[<0>] xfs_fs_fill_super+0x10ec/0x1b20
[<0>] get_tree_bdev+0x3c8/0x730
[<0>] vfs_get_tree+0x89/0x2c0
[<0>] path_mount+0xecf/0x1800
[<0>] do_mount+0xf3/0x110
[<0>] __x64_sys_mount+0x154/0x1f0
[<0>] do_syscall_64+0x39/0x80
[<0>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
When newly created intent items fail to commit via transaction, intent
recovery hasn't created done items for these newly created intent items,
so the capture structure is the sole owner of the captured intent items.
We must release them explicitly or else they leak:
unreferenced object 0xffff888016719108 (size 432):
comm "mount", pid 529, jiffies 4294706839 (age 144.463s)
hex dump (first 32 bytes):
08 91 71 16 80 88 ff ff 08 91 71 16 80 88 ff ff ..q.......q.....
18 91 71 16 80 88 ff ff 18 91 71 16 80 88 ff ff ..q.......q.....
backtrace:
[<ffffffff8230c68f>] xfs_efi_init+0x18f/0x1d0
[<ffffffff8230c720>] xfs_extent_free_create_intent+0x50/0x150
[<ffffffff821b671a>] xfs_defer_create_intents+0x16a/0x340
[<ffffffff821bac3e>] xfs_defer_ops_capture_and_commit+0x8e/0xad0
[<ffffffff82322bb9>] xfs_cui_item_recover+0x819/0x980
[<ffffffff823289b6>] xlog_recover_process_intents+0x246/0xb70
[<ffffffff8233249a>] xlog_recover_finish+0x8a/0x9a0
[<ffffffff822eeafb>] xfs_log_mount_finish+0x2bb/0x4a0
[<ffffffff822c0f4f>] xfs_mountfs+0x14bf/0x1e70
[<ffffffff822d1f80>] xfs_fs_fill_super+0x10d0/0x1b20
[<ffffffff81a21fa2>] get_tree_bdev+0x3d2/0x6d0
[<ffffffff81a1ee09>] vfs_get_tree+0x89/0x2c0
[<ffffffff81a9f35f>] path_mount+0xecf/0x1800
[<ffffffff81a9fd83>] do_mount+0xf3/0x110
[<ffffffff81aa00e4>] __x64_sys_mount+0x154/0x1f0
[<ffffffff83968739>] do_syscall_64+0x39/0x80
Fix the problem above by abort intent items that don't have a done item
when recovery intents fail.
Fixes: e6fff81e48 ("xfs: proper replay of deferred ops queued during log recovery")
Signed-off-by: Long Li <leo.lilong@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 2a5db859c6 upstream.
Factor out xfs_defer_pending_abort() from xfs_defer_trans_abort(), which
not use transaction parameter, so it can be used after the transaction
life cycle.
Signed-off-by: Long Li <leo.lilong@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 14a537983b upstream.
One of our VM cluster management products needs to snapshot KVM image
files so that they can be restored in case of failure. Snapshotting is
done by redirecting VM disk writes to a sidecar file and using reflink
on the disk image, specifically the FICLONE ioctl as used by
"cp --reflink". Reflink locks the source and destination files while it
operates, which means that reads from the main vm disk image are blocked,
causing the vm to stall. When an image file is heavily fragmented, the
copy process could take several minutes. Some of the vm image files have
50-100 million extent records, and duplicating that much metadata locks
the file for 30 minutes or more. Having activities suspended for such
a long time in a cluster node could result in node eviction.
Clone operations and read IO do not change any data in the source file,
so they should be able to run concurrently. Demote the exclusive locks
taken by FICLONE to shared locks to allow reads while cloning. While a
clone is in progress, writes will take the IOLOCK_EXCL, so they block
until the clone completes.
Link: https://lore.kernel.org/linux-xfs/8911B94D-DD29-4D6E-B5BC-32EAF1866245@oracle.com/
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 35dc55b9e8 upstream.
If xfs_bmapi_write finds a delalloc extent at the requested range, it
tries to convert the entire delalloc extent to a real allocation.
But if the allocator cannot find a single free extent large enough to
cover the start block of the requested range, xfs_bmapi_write will
return 0 but leave *nimaps set to 0.
In that case we simply need to keep looping with the same startoffset_fsb
so that one of the following allocations will eventually reach the
requested range.
Note that this could affect any caller of xfs_bmapi_write that covers
an existing delayed allocation. As far as I can tell we do not have
any other such caller, though - the regular writeback path uses
xfs_bmapi_convert_delalloc to convert delayed allocations to real ones,
and direct I/O invalidates the page cache first.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 2b99e410b2 upstream.
When abnormal drop_nlink are detected on the inode,
return error, to avoid corruption propagation.
Signed-off-by: Cheng Lin <cheng.lin130@zte.com.cn>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f6a2dae2a1 upstream.
In commit 2a6ca4baed, we tried to fix an overflow problem in the
realtime allocator that was caused by an overly large maxlen value
causing xfs_rtcheck_range to run off the end of the realtime bitmap.
Unfortunately, there is a subtle bug here -- maxlen (and minlen) both
have to be aligned with @prod, but @prod can be larger than 1 if the
user has set an extent size hint on the file, and that extent size hint
is larger than the realtime extent size.
If the rt free space extents are not aligned to this file's extszhint
because other files without extent size hints allocated space (or the
number of rt extents is similarly not aligned), then it's possible that
maxlen after clamping to sb_rextents will no longer be aligned to prod.
The allocation will succeed just fine, but we still trip the assertion.
Fix the problem by reducing maxlen by any misalignment with prod. While
we're at it, split the assertions into two so that we can tell which
value had the bad alignment.
Fixes: 2a6ca4baed ("xfs: make sure the rt allocator doesn't run off the end")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ddd98076d5 upstream.
The unit conversions in this function do not make sense. First we
convert a block count to bytes, then divide that bytes value by
rextsize, which is in blocks, to get an rt extent count. You can't
divide bytes by blocks to get a (possibly multiblock) extent value.
Fortunately nobody uses delalloc on the rt volume so this hasn't
mattered.
Fixes: fa5c836ca8 ("xfs: refactor xfs_bunmapi_cow")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
