commit 02c418774f76a0a36a6195c9dbf8971eb4130a15 upstream. Unlock cifs_tcp_ses_lock before calling cifs_put_smb_ses() to avoid such deadlock. Cc: stable@vger.kernel.org Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Reviewed-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 7373a51e7998b508af7136530f3a997b286ce81c upstream.
The error handling in nilfs_empty_dir() when a directory folio/page read
fails is incorrect, as in the old ext2 implementation, and if the
folio/page cannot be read or nilfs_check_folio() fails, it will falsely
determine the directory as empty and corrupt the file system.
In addition, since nilfs_empty_dir() does not immediately return on a
failed folio/page read, but continues to loop, this can cause a long loop
with I/O if i_size of the directory's inode is also corrupted, causing the
log writer thread to wait and hang, as reported by syzbot.
Fix these issues by making nilfs_empty_dir() immediately return a false
value (0) if it fails to get a directory folio/page.
Link: https://lkml.kernel.org/r/20240604134255.7165-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+c8166c541d3971bf6c87@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c8166c541d3971bf6c87
Fixes: 2ba466d74ed7 ("nilfs2: directory entry operations")
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 a4ca369ca221bb7e06c725792ac107f0e48e82e7 upstream.
Destructive writes to a block device on which nilfs2 is mounted can cause
a kernel bug in the folio/page writeback start routine or writeback end
routine (__folio_start_writeback in the log below):
kernel BUG at mm/page-writeback.c:3070!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
...
RIP: 0010:__folio_start_writeback+0xbaa/0x10e0
Code: 25 ff 0f 00 00 0f 84 18 01 00 00 e8 40 ca c6 ff e9 17 f6 ff ff
e8 36 ca c6 ff 4c 89 f7 48 c7 c6 80 c0 12 84 e8 e7 b3 0f 00 90 <0f>
0b e8 1f ca c6 ff 4c 89 f7 48 c7 c6 a0 c6 12 84 e8 d0 b3 0f 00
...
Call Trace:
<TASK>
nilfs_segctor_do_construct+0x4654/0x69d0 [nilfs2]
nilfs_segctor_construct+0x181/0x6b0 [nilfs2]
nilfs_segctor_thread+0x548/0x11c0 [nilfs2]
kthread+0x2f0/0x390
ret_from_fork+0x4b/0x80
ret_from_fork_asm+0x1a/0x30
</TASK>
This is because when the log writer starts a writeback for segment summary
blocks or a super root block that use the backing device's page cache, it
does not wait for the ongoing folio/page writeback, resulting in an
inconsistent writeback state.
Fix this issue by waiting for ongoing writebacks when putting
folios/pages on the backing device into writeback state.
Link: https://lkml.kernel.org/r/20240530141556.4411-1-konishi.ryusuke@gmail.com
Fixes: 9ff05123e3bf ("nilfs2: segment constructor")
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 440861b1a03c72cc7be4a307e178dcaa6894479b upstream.
Although 'norecovery' mount option was marked as deprecated for a long
time and a warning message was printed during the deprecation window,
it's still actively utilized by several projects that need a safer way
to mount a btrfs without any writes.
Furthermore this 'norecovery' mount option is supported by other major
filesystems, which makes it less clear what's our motivation to remove
it.
Re-introduce the 'norecovery' mount option, and output a message to recommend
'rescue=nologreplay' option.
Link: https://lore.kernel.org/linux-btrfs/ZkxZT0J-z0GYvfy8@gardel-login/#t
Link: https://github.com/systemd/systemd/pull/32892
Link: https://bugzilla.suse.com/show_bug.cgi?id=1222429
Reported-by: Lennart Poettering <lennart@poettering.net>
Reported-by: Jiri Slaby <jslaby@suse.com>
Fixes: a1912f712188 ("btrfs: remove code for inode_cache and recovery mount options")
CC: stable@vger.kernel.org # 6.8+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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 fb33eb2ef0d88e75564983ef057b44c5b7e4fded upstream.
Qgroup extent records are created when delayed ref heads are created and
then released after accounting extents at btrfs_qgroup_account_extents(),
called during the transaction commit path.
If a transaction is aborted we free the qgroup records by calling
btrfs_qgroup_destroy_extent_records() at btrfs_destroy_delayed_refs(),
unless we don't have delayed references. We are incorrectly assuming
that no delayed references means we don't have qgroup extents records.
We can currently have no delayed references because we ran them all
during a transaction commit and the transaction was aborted after that
due to some error in the commit path.
So fix this by ensuring we btrfs_qgroup_destroy_extent_records() at
btrfs_destroy_delayed_refs() even if we don't have any delayed references.
Reported-by: syzbot+0fecc032fa134afd49df@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/0000000000004e7f980619f91835@google.com/
Fixes: 81f7eb00ff5b ("btrfs: destroy qgroup extent records on transaction abort")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9d274c19a71b3a276949933859610721a453946b upstream.
We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():
BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
------------[ cut here ]------------
kernel BUG at fs/btrfs/ctree.c:2620!
invalid opcode: 0000 [#1] PREEMPT SMP PTI
CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]
With the following stack trace:
#0 btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
#1 btrfs_drop_extents (fs/btrfs/file.c:411:4)
#2 log_one_extent (fs/btrfs/tree-log.c:4732:9)
#3 btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
#4 btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
#5 btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
#6 btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
#7 btrfs_sync_file (fs/btrfs/file.c:1933:8)
#8 vfs_fsync_range (fs/sync.c:188:9)
#9 vfs_fsync (fs/sync.c:202:9)
#10 do_fsync (fs/sync.c:212:9)
#11 __do_sys_fdatasync (fs/sync.c:225:9)
#12 __se_sys_fdatasync (fs/sync.c:223:1)
#13 __x64_sys_fdatasync (fs/sync.c:223:1)
#14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
#15 do_syscall_64 (arch/x86/entry/common.c:83:7)
#16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)
So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().
This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:
>>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
leaf 33439744 flags 0x100000000000000
fs uuid e5bd3946-400c-4223-8923-190ef1f18677
chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
generation 7 transid 9 size 8192 nbytes 8473563889606862198
block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
sequence 204 flags 0x10(PREALLOC)
atime 1716417703.220000000 (2024-05-22 15:41:43)
ctime 1716417704.983333333 (2024-05-22 15:41:44)
mtime 1716417704.983333333 (2024-05-22 15:41:44)
otime 17592186044416.000000000 (559444-03-08 01:40:16)
item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
index 195 namelen 3 name: 193
item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
location key (0 UNKNOWN.0 0) type XATTR
transid 7 data_len 1 name_len 6
name: user.a
data a
item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
generation 9 type 1 (regular)
extent data disk byte 303144960 nr 12288
extent data offset 0 nr 4096 ram 12288
extent compression 0 (none)
item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
generation 9 type 2 (prealloc)
prealloc data disk byte 303144960 nr 12288
prealloc data offset 4096 nr 8192
item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
generation 9 type 2 (prealloc)
prealloc data disk byte 303144960 nr 12288
prealloc data offset 8192 nr 4096
...
So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.
Here is the state of the filesystem tree at the time of the crash:
>>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
>>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
>>> print_extent_buffer(nodes[0])
leaf 30425088 level 0 items 184 generation 9 owner 5
leaf 30425088 flags 0x100000000000000
fs uuid e5bd3946-400c-4223-8923-190ef1f18677
chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
...
item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
generation 7 transid 7 size 4096 nbytes 12288
block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
sequence 6 flags 0x10(PREALLOC)
atime 1716417703.220000000 (2024-05-22 15:41:43)
ctime 1716417703.220000000 (2024-05-22 15:41:43)
mtime 1716417703.220000000 (2024-05-22 15:41:43)
otime 1716417703.220000000 (2024-05-22 15:41:43)
item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
index 195 namelen 3 name: 193
item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
location key (0 UNKNOWN.0 0) type XATTR
transid 7 data_len 1 name_len 6
name: user.a
data a
item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
generation 9 type 1 (regular)
extent data disk byte 303144960 nr 12288
extent data offset 0 nr 8192 ram 12288
extent compression 0 (none)
item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
generation 9 type 2 (prealloc)
prealloc data disk byte 303144960 nr 12288
prealloc data offset 8192 nr 4096
Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.
btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.
If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.
This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:
- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
to the log tree.
- An xattr is set on the file, which sets the
BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
calls copy_inode_items_to_log(), which calls
btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
filesystem tree. Since it starts before i_size, it skips it. Since it
is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
the prealloc extent to written and inserts the remaining prealloc part
from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
the log tree. Note that it overlaps with the 4k-12k prealloc extent
that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
adjusting the start of the 4k-12k prealloc extent in the log tree to
8k.
- btrfs_set_item_key_safe() sees that there is already an extent
starting at 8k in the log tree and calls BUG().
Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f3a5367c679d31473d3fbb391675055b4792c309 upstream.
[BUG]
Since v6.8 there are rare kernel crashes reported by various people,
the common factor is bad page status error messages like this:
BUG: Bad page state in process kswapd0 pfn:d6e840
page: refcount:0 mapcount:0 mapping:000000007512f4f2 index:0x2796c2c7c
pfn:0xd6e840
aops:btree_aops ino:1
flags: 0x17ffffe0000008(uptodate|node=0|zone=2|lastcpupid=0x3fffff)
page_type: 0xffffffff()
raw: 0017ffffe0000008 dead000000000100 dead000000000122 ffff88826d0be4c0
raw: 00000002796c2c7c 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: non-NULL mapping
[CAUSE]
Commit 09e6cef19c9f ("btrfs: refactor alloc_extent_buffer() to
allocate-then-attach method") changes the sequence when allocating a new
extent buffer.
Previously we always called grab_extent_buffer() under
mapping->i_private_lock, to ensure the safety on modification on
folio::private (which is a pointer to extent buffer for regular
sectorsize).
This can lead to the following race:
Thread A is trying to allocate an extent buffer at bytenr X, with 4
4K pages, meanwhile thread B is trying to release the page at X + 4K
(the second page of the extent buffer at X).
Thread A | Thread B
-----------------------------------+-------------------------------------
| btree_release_folio()
| | This is for the page at X + 4K,
| | Not page X.
| |
alloc_extent_buffer() | |- release_extent_buffer()
|- filemap_add_folio() for the | | |- atomic_dec_and_test(eb->refs)
| page at bytenr X (the first | | |
| page). | | |
| Which returned -EEXIST. | | |
| | | |
|- filemap_lock_folio() | | |
| Returned the first page locked. | | |
| | | |
|- grab_extent_buffer() | | |
| |- atomic_inc_not_zero() | | |
| | Returned false | | |
| |- folio_detach_private() | | |- folio_detach_private() for X
| |- folio_test_private() | | |- folio_test_private()
| Returned true | | | Returned true
|- folio_put() | |- folio_put()
Now there are two puts on the same folio at folio X, leading to refcount
underflow of the folio X, and eventually causing the BUG_ON() on the
page->mapping.
The condition is not that easy to hit:
- The release must be triggered for the middle page of an eb
If the release is on the same first page of an eb, page lock would kick
in and prevent the race.
- folio_detach_private() has a very small race window
It's only between folio_test_private() and folio_clear_private().
That's exactly when mapping->i_private_lock is used to prevent such race,
and commit 09e6cef19c9f ("btrfs: refactor alloc_extent_buffer() to
allocate-then-attach method") screwed that up.
At that time, I thought the page lock would kick in as
filemap_release_folio() also requires the page to be locked, but forgot
the filemap_release_folio() only locks one page, not all pages of an
extent buffer.
[FIX]
Move all the code requiring i_private_lock into
attach_eb_folio_to_filemap(), so that everything is done with proper
lock protection.
Furthermore to prevent future problems, add an extra
lockdep_assert_locked() to ensure we're holding the proper lock.
To reproducer that is able to hit the race (takes a few minutes with
instrumented code inserting delays to alloc_extent_buffer()):
#!/bin/sh
drop_caches () {
while(true); do
echo 3 > /proc/sys/vm/drop_caches
echo 1 > /proc/sys/vm/compact_memory
done
}
run_tar () {
while(true); do
for x in `seq 1 80` ; do
tar cf /dev/zero /mnt > /dev/null &
done
wait
done
}
mkfs.btrfs -f -d single -m single /dev/vda
mount -o noatime /dev/vda /mnt
# create 200,000 files, 1K each
./simoop -n 200000 -E -f 1k /mnt
drop_caches &
(run_tar)
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/linux-btrfs/CAHk-=wgt362nGfScVOOii8cgKn2LVVHeOvOA7OBwg1OwbuJQcw@mail.gmail.com/
Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Link: https://lore.kernel.org/lkml/CABXGCsPktcHQOvKTbPaTwegMExije=Gpgci5NW=hqORo-s7diA@mail.gmail.com/
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Link: https://lore.kernel.org/linux-btrfs/e8b3311c-9a75-4903-907f-fc0f7a3fe423@gmx.de/
Reported-by: syzbot+f80b066392366b4af85e@syzkaller.appspotmail.com
Fixes: 09e6cef19c9f ("btrfs: refactor alloc_extent_buffer() to allocate-then-attach method")
CC: stable@vger.kernel.org # 6.8+
CC: Chris Mason <clm@fb.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.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 2b8aa78cf1279ec5e418baa26bfed5df682568d8 upstream.
If we delete subvolumes whose ID is the largest in the filesystem, then
unmount and mount again, then btrfs_init_root_free_objectid on the
tree_root will select a subvolid smaller than that one and thus allow
reusing it.
If we are also using qgroups (and particularly squotas) it is possible
to delete the subvol without deleting the qgroup. In that case, we will
be able to create a new subvol whose id already has a level 0 qgroup.
This will result in re-using that qgroup which would then lead to
incorrect accounting.
Fixes: 6ed05643ddb1 ("btrfs: create qgroup earlier in snapshot creation")
CC: stable@vger.kernel.org # 6.7+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1fa7603d569b9e738e9581937ba8725cd7d39b48 upstream. On filesystems without enabled quotas there's still a warning message in the logs when rescan is called. In that case it's not a problem that should be reported, rescan can be called unconditionally. Change the error code to ENOTCONN which is used for 'quotas not enabled' elsewhere. Remove message (also a warning) when rescan is called during an ongoing rescan, this brings no useful information and the error code is sufficient. Change message levels to debug for now, they can be removed eventually. CC: stable@vger.kernel.org # 6.6+ Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0bcfd9aa4dafa03b88d68bf66b694df2a3e76cf3 upstream.
When the inode is being dropped from the dentry, the TRACEFS_EVENT_INODE
flag needs to be cleared to prevent a remount from calling
eventfs_remount() on the tracefs_inode private data. There's a race
between the inode is dropped (and the dentry freed) to where the inode is
actually freed. If a remount happens between the two, the eventfs_inode
could be accessed after it is freed (only the dentry keeps a ref count on
it).
Currently the TRACEFS_EVENT_INODE flag is cleared from the dentry iput()
function. But this is incorrect, as it is possible that the inode has
another reference to it. The flag should only be cleared when the inode is
really being dropped and has no more references. That happens in the
drop_inode callback of the inode, as that gets called when the last
reference of the inode is released.
Remove the tracefs_d_iput() function and move its logic to the more
appropriate tracefs_drop_inode() callback function.
Link: https://lore.kernel.org/linux-trace-kernel/20240523051539.908205106@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: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Fixes: baa23a8d4360d ("tracefs: Reset permissions on remount if permissions are options")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>