84461 Commits

Author SHA1 Message Date
Steven Rostedt (Google)
32f4c167cb eventfs: Save ownership and mode
commit 28e12c09f5aa081b2d13d1340e3610070b6c624d 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: 63940449555e7 ("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>
2024-02-23 09:25:20 +01:00
Steven Rostedt (Google)
d2a632aeec eventfs: Test for ei->is_freed when accessing ei->dentry
commit 77a06c33a22d13f3a6e31f06f6ee6bca666e6898 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: 5790b1fb3d672 ("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>
2024-02-23 09:25:20 +01:00
Steven Rostedt (Google)
6e2a33522e eventfs: Have a free_ei() that just frees the eventfs_inode
commit db3a397209b00d2e4e0a068608e5c546fc064b82 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>
2024-02-23 09:25:20 +01:00
Steven Rostedt (Google)
4bb123ce29 eventfs: Remove "is_freed" union with rcu head
commit f2f496370afcbc5227d7002da28c74b91fed12ff 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: 63940449555e7 ("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>
2024-02-23 09:25:20 +01:00
Steven Rostedt (Google)
773cd7dfd0 eventfs: Fix kerneldoc of eventfs_remove_rec()
commit 9037caa09ed345b35325200f0e4acf5a94ae0a65 upstream.

The eventfs_remove_rec() had some missing parameters in the kerneldoc
comment above it. Also, rephrase the description a bit more to have a bit
more correct grammar.

Link: https://lore.kernel.org/linux-trace-kernel/20231030121523.0b2225a7@gandalf.local.home

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Fixes: 5790b1fb3d672 ("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/202310052216.4SgqasWo-lkp@intel.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:20 +01:00
Steven Rostedt (Google)
810a957e34 eventfs: Remove extra dget() in eventfs_create_events_dir()
commit 77bc4d4921bd3497678ba8e7f4e480de35692f05 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: 5790b1fb3d672 ("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>
2024-02-23 09:25:20 +01:00
Steven Rostedt (Google)
7cac392f56 eventfs: Fix typo in eventfs_inode union comment
commit 29e06c10702e81a7d0b75020ca514d2f2962704a upstream.

It's eventfs_inode not eventfs_indoe. There's no deer involved!

Link: https://lore.kernel.org/linux-trace-kernel/20231024131024.5634c743@gandalf.local.home

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Fixes: 5790b1fb3d672 ("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>
2024-02-23 09:25:20 +01:00
Steven Rostedt (Google)
f7842e0617 eventfs: Fix WARN_ON() in create_file_dentry()
commit a9de4eb15ad430fe45747c211e367da745a90093 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: 5790b1fb3d672 ("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>
2024-02-23 09:25:20 +01:00
Jiapeng Chong
843879a6dd tracefs/eventfs: Modify mismatched function name
commit 64bf2f685c795e75dd855761c75a193ee5998731 upstream.

No functional modification involved.

fs/tracefs/event_inode.c:864: warning: expecting prototype for eventfs_remove(). Prototype was for eventfs_remove_dir() instead.

Link: https://lore.kernel.org/linux-trace-kernel/20231019031353.73846-1-jiapeng.chong@linux.alibaba.com

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=6939
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:19 +01:00
Steven Rostedt (Google)
c99e5cfe77 eventfs: Fix failure path in eventfs_create_events_dir()
commit 7e8ad67c9b5c11e990c320ed7e7563f2301672a7 upstream.

The failure path of allocating ei goes to a path that dereferences ei.
Add another label that skips over the ei dereferences to do the rest of
the clean up.

Link: https://lore.kernel.org/all/70e7bace-561c-95f-1117-706c2c220bc@inria.fr/
Link: https://lore.kernel.org/linux-trace-kernel/20231019204132.6662fef0@gandalf.local.home

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Fixes: 5790b1fb3d67 ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:19 +01:00
Nathan Chancellor
17e4e4d233 eventfs: Use ERR_CAST() in eventfs_create_events_dir()
commit b8a555dc31e5aa18d976de0bc228006e398a2e7d 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: 5790b1fb3d67 ("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>
2024-02-23 09:25:19 +01:00
Steven Rostedt (Google)
bceba0d35b eventfs: Use eventfs_remove_events_dir()
commit 2819f23ac12ce93ff79ca7a54597df9a4a1f6331 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: 5790b1fb3d67 ("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>
2024-02-23 09:25:19 +01:00
Steven Rostedt (Google)
35ee34c0f6 eventfs: Remove eventfs_file and just use eventfs_inode
commit 5790b1fb3d672d9a1fe3881a7181dfdbe741568f 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>
2024-02-23 09:25:19 +01:00
Steven Rostedt (Google)
4015fc4927 Revert "eventfs: Remove "is_freed" union with rcu head"
This reverts commit fa18a8a0539b02cc621938091691f0b73f0b1288.

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>
2024-02-23 09:25:19 +01:00
Steven Rostedt (Google)
dc9ee9a8ae Revert "eventfs: Save ownership and mode"
This reverts commit 9aaee3eebc91dd9ccebf6b6bc8a5f59d04ef718b.

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>
2024-02-23 09:25:19 +01:00
Steven Rostedt (Google)
65a54d6dbf Revert "eventfs: Delete eventfs_inode when the last dentry is freed"
This reverts commit ea4c30a0a73fb5cb2604539db550f1e620bb949c.

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>
2024-02-23 09:25:19 +01:00
Steven Rostedt (Google)
601daf7e31 Revert "eventfs: Use simple_recursive_removal() to clean up dentries"
This reverts commit 055907ad2c14838c90d63297f7bab8d180a5d844.

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>
2024-02-23 09:25:18 +01:00
Steven Rostedt (Google)
5e9fb47619 Revert "eventfs: Check for NULL ef in eventfs_set_attr()"
This reverts commit d8f492a059728bbd397defbc9b8d2f4159d869b5.

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>
2024-02-23 09:25:18 +01:00
Steven Rostedt (Google)
6fdc0bcd06 Revert "eventfs: Do not allow NULL parent to eventfs_start_creating()"
This reverts commit 6abb8c223ce12078a0f2c129656a13338dfe960b.

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>
2024-02-23 09:25:18 +01:00
Oleg Nesterov
5d858e2d3e fs/proc: do_task_stat: move thread_group_cputime_adjusted() outside of lock_task_sighand()
commit 60f92acb60a989b14e4b744501a0df0f82ef30a3 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>
2024-02-23 09:25:17 +01:00
Prakash Sangappa
4d850ed747 mm: hugetlb pages should not be reserved by shmat() if SHM_NORESERVE
commit e656c7a9e59607d1672d85ffa9a89031876ffe67 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>
2024-02-23 09:25:16 +01:00
Oscar Salvador
13c5a9fb07 fs,hugetlb: fix NULL pointer dereference in hugetlbs_fill_super
commit 79d72c68c58784a3e1cd2378669d51bfd0cb7498 upstream.

When configuring a hugetlb filesystem via the fsconfig() syscall, there is
a possible NULL dereference in hugetlbfs_fill_super() caused by assigning
NULL to ctx->hstate in hugetlbfs_parse_param() when the requested pagesize
is non valid.

E.g: Taking the following steps:

     fd = fsopen("hugetlbfs", FSOPEN_CLOEXEC);
     fsconfig(fd, FSCONFIG_SET_STRING, "pagesize", "1024", 0);
     fsconfig(fd, FSCONFIG_CMD_CREATE, NULL, NULL, 0);

Given that the requested "pagesize" is invalid, ctxt->hstate will be replaced
with NULL, losing its previous value, and we will print an error:

 ...
 ...
 case Opt_pagesize:
 ps = memparse(param->string, &rest);
 ctx->hstate = h;
 if (!ctx->hstate) {
         pr_err("Unsupported page size %lu MB\n", ps / SZ_1M);
         return -EINVAL;
 }
 return 0;
 ...
 ...

This is a problem because later on, we will dereference ctxt->hstate in
hugetlbfs_fill_super()

 ...
 ...
 sb->s_blocksize = huge_page_size(ctx->hstate);
 ...
 ...

Causing below Oops.

Fix this by replacing cxt->hstate value only when then pagesize is known
to be valid.

 kernel: hugetlbfs: Unsupported page size 0 MB
 kernel: BUG: kernel NULL pointer dereference, address: 0000000000000028
 kernel: #PF: supervisor read access in kernel mode
 kernel: #PF: error_code(0x0000) - not-present page
 kernel: PGD 800000010f66c067 P4D 800000010f66c067 PUD 1b22f8067 PMD 0
 kernel: Oops: 0000 [#1] PREEMPT SMP PTI
 kernel: CPU: 4 PID: 5659 Comm: syscall Tainted: G            E      6.8.0-rc2-default+ #22 5a47c3fef76212addcc6eb71344aabc35190ae8f
 kernel: Hardware name: Intel Corp. GROVEPORT/GROVEPORT, BIOS GVPRCRB1.86B.0016.D04.1705030402 05/03/2017
 kernel: RIP: 0010:hugetlbfs_fill_super+0xb4/0x1a0
 kernel: Code: 48 8b 3b e8 3e c6 ed ff 48 85 c0 48 89 45 20 0f 84 d6 00 00 00 48 b8 ff ff ff ff ff ff ff 7f 4c 89 e7 49 89 44 24 20 48 8b 03 <8b> 48 28 b8 00 10 00 00 48 d3 e0 49 89 44 24 18 48 8b 03 8b 40 28
 kernel: RSP: 0018:ffffbe9960fcbd48 EFLAGS: 00010246
 kernel: RAX: 0000000000000000 RBX: ffff9af5272ae780 RCX: 0000000000372004
 kernel: RDX: ffffffffffffffff RSI: ffffffffffffffff RDI: ffff9af555e9b000
 kernel: RBP: ffff9af52ee66b00 R08: 0000000000000040 R09: 0000000000370004
 kernel: R10: ffffbe9960fcbd48 R11: 0000000000000040 R12: ffff9af555e9b000
 kernel: R13: ffffffffa66b86c0 R14: ffff9af507d2f400 R15: ffff9af507d2f400
 kernel: FS:  00007ffbc0ba4740(0000) GS:ffff9b0bd7000000(0000) knlGS:0000000000000000
 kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 kernel: CR2: 0000000000000028 CR3: 00000001b1ee0000 CR4: 00000000001506f0
 kernel: Call Trace:
 kernel:  <TASK>
 kernel:  ? __die_body+0x1a/0x60
 kernel:  ? page_fault_oops+0x16f/0x4a0
 kernel:  ? search_bpf_extables+0x65/0x70
 kernel:  ? fixup_exception+0x22/0x310
 kernel:  ? exc_page_fault+0x69/0x150
 kernel:  ? asm_exc_page_fault+0x22/0x30
 kernel:  ? __pfx_hugetlbfs_fill_super+0x10/0x10
 kernel:  ? hugetlbfs_fill_super+0xb4/0x1a0
 kernel:  ? hugetlbfs_fill_super+0x28/0x1a0
 kernel:  ? __pfx_hugetlbfs_fill_super+0x10/0x10
 kernel:  vfs_get_super+0x40/0xa0
 kernel:  ? __pfx_bpf_lsm_capable+0x10/0x10
 kernel:  vfs_get_tree+0x25/0xd0
 kernel:  vfs_cmd_create+0x64/0xe0
 kernel:  __x64_sys_fsconfig+0x395/0x410
 kernel:  do_syscall_64+0x80/0x160
 kernel:  ? syscall_exit_to_user_mode+0x82/0x240
 kernel:  ? do_syscall_64+0x8d/0x160
 kernel:  ? syscall_exit_to_user_mode+0x82/0x240
 kernel:  ? do_syscall_64+0x8d/0x160
 kernel:  ? exc_page_fault+0x69/0x150
 kernel:  entry_SYSCALL_64_after_hwframe+0x6e/0x76
 kernel: RIP: 0033:0x7ffbc0cb87c9
 kernel: Code: 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 97 96 0d 00 f7 d8 64 89 01 48
 kernel: RSP: 002b:00007ffc29d2f388 EFLAGS: 00000206 ORIG_RAX: 00000000000001af
 kernel: RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffbc0cb87c9
 kernel: RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003
 kernel: RBP: 00007ffc29d2f3b0 R08: 0000000000000000 R09: 0000000000000000
 kernel: R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
 kernel: R13: 00007ffc29d2f4c0 R14: 0000000000000000 R15: 0000000000000000
 kernel:  </TASK>
 kernel: Modules linked in: rpcsec_gss_krb5(E) auth_rpcgss(E) nfsv4(E) dns_resolver(E) nfs(E) lockd(E) grace(E) sunrpc(E) netfs(E) af_packet(E) bridge(E) stp(E) llc(E) iscsi_ibft(E) iscsi_boot_sysfs(E) intel_rapl_msr(E) intel_rapl_common(E) iTCO_wdt(E) intel_pmc_bxt(E) sb_edac(E) iTCO_vendor_support(E) x86_pkg_temp_thermal(E) intel_powerclamp(E) coretemp(E) kvm_intel(E) rfkill(E) ipmi_ssif(E) kvm(E) acpi_ipmi(E) irqbypass(E) pcspkr(E) igb(E) ipmi_si(E) mei_me(E) i2c_i801(E) joydev(E) intel_pch_thermal(E) i2c_smbus(E) dca(E) lpc_ich(E) mei(E) ipmi_devintf(E) ipmi_msghandler(E) acpi_pad(E) tiny_power_button(E) button(E) fuse(E) efi_pstore(E) configfs(E) ip_tables(E) x_tables(E) ext4(E) mbcache(E) jbd2(E) hid_generic(E) usbhid(E) sd_mod(E) t10_pi(E) crct10dif_pclmul(E) crc32_pclmul(E) crc32c_intel(E) polyval_clmulni(E) ahci(E) xhci_pci(E) polyval_generic(E) gf128mul(E) ghash_clmulni_intel(E) sha512_ssse3(E) sha256_ssse3(E) xhci_pci_renesas(E) libahci(E) ehci_pci(E) sha1_ssse3(E) xhci_hcd(E) ehci_hcd(E) libata(E)
 kernel:  mgag200(E) i2c_algo_bit(E) usbcore(E) wmi(E) sg(E) dm_multipath(E) dm_mod(E) scsi_dh_rdac(E) scsi_dh_emc(E) scsi_dh_alua(E) scsi_mod(E) scsi_common(E) aesni_intel(E) crypto_simd(E) cryptd(E)
 kernel: Unloaded tainted modules: acpi_cpufreq(E):1 fjes(E):1
 kernel: CR2: 0000000000000028
 kernel: ---[ end trace 0000000000000000 ]---
 kernel: RIP: 0010:hugetlbfs_fill_super+0xb4/0x1a0
 kernel: Code: 48 8b 3b e8 3e c6 ed ff 48 85 c0 48 89 45 20 0f 84 d6 00 00 00 48 b8 ff ff ff ff ff ff ff 7f 4c 89 e7 49 89 44 24 20 48 8b 03 <8b> 48 28 b8 00 10 00 00 48 d3 e0 49 89 44 24 18 48 8b 03 8b 40 28
 kernel: RSP: 0018:ffffbe9960fcbd48 EFLAGS: 00010246
 kernel: RAX: 0000000000000000 RBX: ffff9af5272ae780 RCX: 0000000000372004
 kernel: RDX: ffffffffffffffff RSI: ffffffffffffffff RDI: ffff9af555e9b000
 kernel: RBP: ffff9af52ee66b00 R08: 0000000000000040 R09: 0000000000370004
 kernel: R10: ffffbe9960fcbd48 R11: 0000000000000040 R12: ffff9af555e9b000
 kernel: R13: ffffffffa66b86c0 R14: ffff9af507d2f400 R15: ffff9af507d2f400
 kernel: FS:  00007ffbc0ba4740(0000) GS:ffff9b0bd7000000(0000) knlGS:0000000000000000
 kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 kernel: CR2: 0000000000000028 CR3: 00000001b1ee0000 CR4: 00000000001506f0

Link: https://lkml.kernel.org/r/20240130210418.3771-1-osalvador@suse.de
Fixes: 32021982a324 ("hugetlbfs: Convert to fs_context")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Oscar Salvador <osalvador@suse.de>
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>
2024-02-23 09:25:16 +01:00
Rishabh Dave
ae20db45e4 ceph: prevent use-after-free in encode_cap_msg()
commit cda4672da1c26835dcbd7aec2bfed954eda9b5ef 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>
2024-02-23 09:25:16 +01:00
Christian Brauner
31f71f2d7a fs: relax mount_setattr() permission checks
commit 46f5ab762d048dad224436978315cbc2fa79c630 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>
2024-02-23 09:25:15 +01:00
Damien Le Moal
6d5eae9a95 zonefs: Improve error handling
commit 14db5f64a971fce3d8ea35de4dfc7f443a3efb92 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: 8dcc1a9d90c1 ("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>
2024-02-23 09:25:13 +01:00
Steve French
4145ccff54 smb: Fix regression in writes when non-standard maximum write size negotiated
commit 4860abb91f3d7fbaf8147d54782149bb1fc45892 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: d08089f649a0 ("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>
2024-02-23 09:25:13 +01:00
Paulo Alcantara
c2aa2718cd smb: client: set correct id, uid and cruid for multiuser automounts
commit 4508ec17357094e2075f334948393ddedbb75157 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: 9fd29a5bae6e ("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>
2024-02-23 09:25:13 +01:00
Ryusuke Konishi
ea5ddbc116 nilfs2: fix hang in nilfs_lookup_dirty_data_buffers()
commit 38296afe3c6ee07319e01bb249aa4bb47c07b534 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: 1d1d1a767206 ("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>
2024-02-23 09:25:11 +01:00
Ryusuke Konishi
2e1480538e nilfs2: fix data corruption in dsync block recovery for small block sizes
commit 67b8bcbaed4777871bb0dcc888fb02a614a98ab1 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>
2024-02-23 09:25:11 +01:00
Fedor Pchelkin
6cef4e6877 ksmbd: free aux buffer if ksmbd_iov_pin_rsp_read fails
commit 108a020c64434fed4b69762879d78cd24088b4c7 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: e2b76ab8b5c9 ("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>
2024-02-23 09:25:07 +01:00
Baokun Li
aafdc920d7 ext4: avoid bb_free and bb_fragments inconsistency in mb_free_blocks()
commit 2331fd4a49864e1571b4f50aa3aa1536ed6220d0 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: eabe0444df90 ("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>
2024-02-23 09:25:05 +01:00
Baokun Li
2883940b19 ext4: fix double-free of blocks due to wrong extents moved_len
commit 55583e899a5357308274601364741a83e78d6ac4 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 94d7c16cbbbd ("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: fcf6b1b729bc ("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>
2024-02-23 09:25:04 +01:00
Dan Carpenter
f7ff1c89fb cifs: fix underflow in parse_server_interfaces()
[ Upstream commit cffe487026be13eaf37ea28b783d9638ab147204 ]

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: fe856be475f7 ("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>
2024-02-23 09:24:58 +01:00
Josef Bacik
7bddf18f47 btrfs: don't drop extent_map for free space inode on write error
commit 5571e41ec6e56e35f34ae9f5b3a335ef510e0ade 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>
2024-02-23 09:24:48 +01:00
Filipe Manana
2f2d903769 btrfs: reject encoded write if inode has nodatasum flag set
commit 1bd96c92c6a0a4d43815eb685c15aa4b78879dc9 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>
2024-02-23 09:24:48 +01:00
Filipe Manana
2dc6dbbddc btrfs: don't reserve space for checksums when writing to nocow files
commit feefe1f49d26bad9d8997096e3a200280fa7b1c5 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>
2024-02-23 09:24:48 +01:00
David Sterba
7efadbcb32 btrfs: send: return EOPNOTSUPP on unknown flags
commit f884a9f9e59206a2d41f265e7e403f080d10b493 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>
2024-02-23 09:24:48 +01:00
Boris Burkov
92182dc179 btrfs: forbid deleting live subvol qgroup
commit a8df35619948bd8363d330c20a90c9a7fbff28c0 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: cecbb533b5fc ("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>
2024-02-23 09:24:48 +01:00
Qu Wenruo
833775656d btrfs: do not ASSERT() if the newly created subvolume already got read
commit e03ee2fe873eb68c1f9ba5112fee70303ebf9dfb 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: 2dfb1e43f57d ("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>
2024-02-23 09:24:47 +01:00
Boris Burkov
4f48ef7d97 btrfs: forbid creating subvol qgroups
commit 0c309d66dacddf8ce939b891d9ead4a8e21ad6f0 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: cecbb533b5fc ("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>
2024-02-23 09:24:47 +01:00
Filipe Manana
505a948d05 btrfs: do not delete unused block group if it may be used soon
commit f4a9f219411f318ae60d6ff7f129082a75686c6c 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>
2024-02-23 09:24:47 +01:00
Filipe Manana
e97ebc2a8c btrfs: add and use helper to check if block group is used
commit 1693d5442c458ae8d5b0d58463b873cd879569ed 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>
2024-02-23 09:24:47 +01:00
Dan Carpenter
fb7bcd1722 fs/ntfs3: Fix an NULL dereference bug
[ Upstream commit b2dd7b953c25ffd5912dda17e980e7168bebcf6c ]

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: be71b5cba2e6 ("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>
2024-02-16 19:10:52 +01:00
Christoph Hellwig
05955a703b xfs: respect the stable writes flag on the RT device
commit 9c04138414c00ae61421f36ada002712c4bac94a 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>
2024-02-16 19:10:46 +01:00
Christoph Hellwig
d7d5ed6536 xfs: clean up FS_XFLAG_REALTIME handling in xfs_ioctl_setattr_xflags
commit c421df0b19430417a04f68919fc3d1943d20ac04 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>
2024-02-16 19:10:46 +01:00
Darrick J. Wong
3581868f51 xfs: dquot recovery does not validate the recovered dquot
commit 9c235dfc3d3f901fe22acb20f2ab37ff39f2ce02 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>
2024-02-16 19:10:46 +01:00
Darrick J. Wong
d744e57880 xfs: clean up dqblk extraction
commit ed17f7da5f0c8b65b7b5f7c98beb0aadbc0546ee 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>
2024-02-16 19:10:46 +01:00
Dave Chinner
b28b234276 xfs: inode recovery does not validate the recovered inode
commit 038ca189c0d2c1570b4d922f25b524007c85cf94 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>
2024-02-16 19:10:45 +01:00
Anthony Iliopoulos
5411625f8d xfs: fix again select in kconfig XFS_ONLINE_SCRUB_STATS
commit a2e4388adfa44684c7c428a5a5980efe0d75e13e upstream.

Commit 57c0f4a8ea3a 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: 57c0f4a8ea3a ("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>
2024-02-16 19:10:45 +01:00
Omar Sandoval
0838177b01 xfs: fix internal error from AGFL exhaustion
commit f63a5b3769ad7659da4c0420751d78958ab97675 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>
2024-02-16 19:10:45 +01:00