[ Upstream commit 1961d20f6f ]
When building the free space tree with the block group tree feature
enabled, we can hit an assertion failure like this:
BTRFS info (device loop0 state M): rebuilding free space tree
assertion failed: ret == 0, in fs/btrfs/free-space-tree.c:1102
------------[ cut here ]------------
kernel BUG at fs/btrfs/free-space-tree.c:1102!
Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
Modules linked in:
CPU: 1 UID: 0 PID: 6592 Comm: syz-executor322 Not tainted 6.15.0-rc7-syzkaller-gd7fa1af5b33e #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : populate_free_space_tree+0x514/0x518 fs/btrfs/free-space-tree.c:1102
lr : populate_free_space_tree+0x514/0x518 fs/btrfs/free-space-tree.c:1102
sp : ffff8000a4ce7600
x29: ffff8000a4ce76e0 x28: ffff0000c9bc6000 x27: ffff0000ddfff3d8
x26: ffff0000ddfff378 x25: dfff800000000000 x24: 0000000000000001
x23: ffff8000a4ce7660 x22: ffff70001499cecc x21: ffff0000e1d8c160
x20: ffff0000e1cb7800 x19: ffff0000e1d8c0b0 x18: 00000000ffffffff
x17: ffff800092f39000 x16: ffff80008ad27e48 x15: ffff700011e740c0
x14: 1ffff00011e740c0 x13: 0000000000000004 x12: ffffffffffffffff
x11: ffff700011e740c0 x10: 0000000000ff0100 x9 : 94ef24f55d2dbc00
x8 : 94ef24f55d2dbc00 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000a4ce6f98 x4 : ffff80008f415ba0 x3 : ffff800080548ef0
x2 : 0000000000000000 x1 : 0000000100000000 x0 : 000000000000003e
Call trace:
populate_free_space_tree+0x514/0x518 fs/btrfs/free-space-tree.c:1102 (P)
btrfs_rebuild_free_space_tree+0x14c/0x54c fs/btrfs/free-space-tree.c:1337
btrfs_start_pre_rw_mount+0xa78/0xe10 fs/btrfs/disk-io.c:3074
btrfs_remount_rw fs/btrfs/super.c:1319 [inline]
btrfs_reconfigure+0x828/0x2418 fs/btrfs/super.c:1543
reconfigure_super+0x1d4/0x6f0 fs/super.c:1083
do_remount fs/namespace.c:3365 [inline]
path_mount+0xb34/0xde0 fs/namespace.c:4200
do_mount fs/namespace.c:4221 [inline]
__do_sys_mount fs/namespace.c:4432 [inline]
__se_sys_mount fs/namespace.c:4409 [inline]
__arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4409
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767
el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Code: f0047182 91178042 528089c3 9771d47b (d4210000)
---[ end trace 0000000000000000 ]---
This happens because we are processing an empty block group, which has
no extents allocated from it, there are no items for this block group,
including the block group item since block group items are stored in a
dedicated tree when using the block group tree feature. It also means
this is the block group with the highest start offset, so there are no
higher keys in the extent root, hence btrfs_search_slot_for_read()
returns 1 (no higher key found).
Fix this by asserting 'ret' is 0 only if the block group tree feature
is not enabled, in which case we should find a block group item for
the block group since it's stored in the extent root and block group
item keys are greater than extent item keys (the value for
BTRFS_BLOCK_GROUP_ITEM_KEY is 192 and for BTRFS_EXTENT_ITEM_KEY and
BTRFS_METADATA_ITEM_KEY the values are 168 and 169 respectively).
In case 'ret' is 1, we just need to add a record to the free space
tree which spans the whole block group, and we can achieve this by
making 'ret == 0' as the while loop's condition.
Reported-by: syzbot+36fae25c35159a763a2a@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/6841dca8.a00a0220.d4325.0020.GAE@google.com/
Reviewed-by: Qu Wenruo <wqu@suse.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: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5f61b96159 ]
When replaying log trees we use read_one_inode() to get an inode, which is
just a wrapper around btrfs_iget_logging(), which in turn is a wrapper for
btrfs_iget(). But read_one_inode() always returns NULL for any error
that btrfs_iget_logging() / btrfs_iget() may return and this is a problem
because:
1) In many callers of read_one_inode() we convert the NULL into -EIO,
which is not accurate since btrfs_iget() may return -ENOMEM and -ENOENT
for example, besides -EIO and other errors. So during log replay we
may end up reporting a false -EIO, which is confusing since we may
not have had any IO error at all;
2) When replaying directory deletes, at replay_dir_deletes(), we assume
the NULL returned from read_one_inode() means that the inode doesn't
exist and then proceed as if no error had happened. This is wrong
because unless btrfs_iget() returned ERR_PTR(-ENOENT), we had an
actual error and the target inode may exist in the target subvolume
root - this may later result in the log replay code failing at a
later stage (if we are "lucky") or succeed but leaving some
inconsistency in the filesystem.
So fix this by not ignoring errors from btrfs_iget_logging() and as
a consequence remove the read_one_inode() wrapper and just use
btrfs_iget_logging() directly. Also since btrfs_iget_logging() is
supposed to be called only against subvolume roots, just like
read_one_inode() which had a comment about it, add an assertion to
btrfs_iget_logging() to check that the target root corresponds to a
subvolume root.
Fixes: 5d4f98a28c ("Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE)")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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: Sasha Levin <sashal@kernel.org>
[ Upstream commit a488d8ac2c ]
All callers of btrfs_iget_logging() are interested in the btrfs_inode
structure rather than the VFS inode, so make btrfs_iget_logging() return
the btrfs_inode instead, avoiding lots of BTRFS_I() calls.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 5f61b96159 ("btrfs: fix inode lookup error handling during log replay")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8befc61cbb ]
The root argument for fixup_inode_link_count() always matches the root of
the given inode, so remove the root argument and get it from the inode
argument. This also applies to the helpers count_inode_extrefs() and
count_inode_refs() used by fixup_inode_link_count() - they don't need the
root argument, as it always matches the root of the inode passed to them.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 5f61b96159 ("btrfs: fix inode lookup error handling during log replay")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0a5d0dc55f ]
The root argument for btrfs_update_inode_fallback() always matches the
root of the given inode, so remove the root argument and get it from the
inode argument.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 5f61b96159 ("btrfs: fix inode lookup error handling during log replay")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cddaaacca9 ]
The noinline attribute of btrfs_update_inode() is pointless as the
function is exported and widely used, so remove it.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 5f61b96159 ("btrfs: fix inode lookup error handling during log replay")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1f2889f559 ]
If we fail to allocate an ordered extent for a COW write we end up leaking
a qgroup data reservation since we called btrfs_qgroup_release_data() but
we didn't call btrfs_qgroup_free_refroot() (which would happen when
running the respective data delayed ref created by ordered extent
completion or when finishing the ordered extent in case an error happened).
So make sure we call btrfs_qgroup_free_refroot() if we fail to allocate an
ordered extent for a COW write.
Fixes: 7dbeaad0af ("btrfs: change timing for qgroup reserved space for ordered extents to fix reserved space leak")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Boris Burkov <boris@bur.io>
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: Sasha Levin <sashal@kernel.org>
[ Upstream commit 157501b046 ]
We are setting the parent directory's last_unlink_trans directly which
may result in a concurrent task starting to log the directory not see the
update and therefore can log the directory after we removed a child
directory which had a snapshot within instead of falling back to a
transaction commit. Replaying such a log tree would result in a mount
failure since we can't currently delete snapshots (and subvolumes) during
log replay. This is the type of failure described in commit 1ec9a1ae1e
("Btrfs: fix unreplayable log after snapshot delete + parent dir fsync").
Fix this by using btrfs_record_snapshot_destroy() which updates the
last_unlink_trans field while holding the inode's log_mutex lock.
Fixes: 44f714dae5 ("Btrfs: improve performance on fsync against new inode after rename/unlink")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c466e33e72 ]
In case the removed directory had a snapshot that was deleted, we are
propagating its inode's last_unlink_trans to the parent directory after
we removed the entry from the parent directory. This leaves a small race
window where someone can log the parent directory after we removed the
entry and before we updated last_unlink_trans, and as a result if we ever
try to replay such a log tree, we will fail since we will attempt to
remove a snapshot during log replay, which is currently not possible and
results in the log replay (and mount) to fail. This is the type of failure
described in commit 1ec9a1ae1e ("Btrfs: fix unreplayable log after
snapshot delete + parent dir fsync").
So fix this by propagating the last_unlink_trans to the parent directory
before we remove the entry from it.
Fixes: 44f714dae5 ("Btrfs: improve performance on fsync against new inode after rename/unlink")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c3a1cc8ff4 ]
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: c466e33e72 ("btrfs: propagate last_unlink_trans earlier when doing a rmdir")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 54a7081ed1 ]
At __inode_add_ref() when processing extrefs, if we jump into the next
label we have an undefined value of victim_name.len, since we haven't
initialized it before we did the goto. This results in an invalid memory
access in the next iteration of the loop since victim_name.len was not
initialized to the length of the name of the current extref.
Fix this by initializing victim_name.len with the current extref's name
length.
Fixes: e43eec81c5 ("btrfs: use struct qstr instead of name and namelen pairs")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6561a40cec ]
During log replay, at __add_inode_ref(), when we are searching for inode
ref keys we totally ignore if btrfs_search_slot() returns an error. This
may make a log replay succeed when there was an actual error and leave
some metadata inconsistency in a subvolume tree. Fix this by checking if
an error was returned from btrfs_search_slot() and if so, return it to
the caller.
Fixes: e02119d5a7 ("Btrfs: Add a write ahead tree log to optimize synchronous operations")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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: Sasha Levin <sashal@kernel.org>
commit ae4477f937 upstream.
Each superblock contains a copy of the device item for that device. In a
transaction which drops a chunk but doesn't create any new ones, we were
correctly updating the device item in the chunk tree but not copying
over the new bytes_used value to the superblock.
This can be seen by doing the following:
# dd if=/dev/zero of=test bs=4096 count=2621440
# mkfs.btrfs test
# mount test /root/temp
# cd /root/temp
# for i in {00..10}; do dd if=/dev/zero of=$i bs=4096 count=32768; done
# sync
# rm *
# sync
# btrfs balance start -dusage=0 .
# sync
# cd
# umount /root/temp
# btrfs check test
For btrfs-check to detect this, you will also need my patch at
https://github.com/kdave/btrfs-progs/pull/991.
Change btrfs_remove_dev_extents() so that it adds the devices to the
fs_info->post_commit_list if they're not there already. This causes
btrfs_commit_device_sizes() to be called, which updates the bytes_used
value in the superblock.
Fixes: bbbf7243d6 ("btrfs: combine device update operations during transaction commit")
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Mark Harmstone <maharmstone@fb.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 3ca864de85 upstream.
We have a race between a rename and directory inode logging that if it
happens and we crash/power fail before the rename completes, the next time
the filesystem is mounted, the log replay code will end up deleting the
file that was being renamed.
This is best explained following a step by step analysis of an interleaving
of steps that lead into this situation.
Consider the initial conditions:
1) We are at transaction N;
2) We have directories A and B created in a past transaction (< N);
3) We have inode X corresponding to a file that has 2 hardlinks, one in
directory A and the other in directory B, so we'll name them as
"A/foo_link1" and "B/foo_link2". Both hard links were persisted in a
past transaction (< N);
4) We have inode Y corresponding to a file that as a single hard link and
is located in directory A, we'll name it as "A/bar". This file was also
persisted in a past transaction (< N).
The steps leading to a file loss are the following and for all of them we
are under transaction N:
1) Link "A/foo_link1" is removed, so inode's X last_unlink_trans field
is updated to N, through btrfs_unlink() -> btrfs_record_unlink_dir();
2) Task A starts a rename for inode Y, with the goal of renaming from
"A/bar" to "A/baz", so we enter btrfs_rename();
3) Task A inserts the new BTRFS_INODE_REF_KEY for inode Y by calling
btrfs_insert_inode_ref();
4) Because the rename happens in the same directory, we don't set the
last_unlink_trans field of directoty A's inode to the current
transaction id, that is, we don't cal btrfs_record_unlink_dir();
5) Task A then removes the entries from directory A (BTRFS_DIR_ITEM_KEY
and BTRFS_DIR_INDEX_KEY items) when calling __btrfs_unlink_inode()
(actually the dir index item is added as a delayed item, but the
effect is the same);
6) Now before task A adds the new entry "A/baz" to directory A by
calling btrfs_add_link(), another task, task B is logging inode X;
7) Task B starts a fsync of inode X and after logging inode X, at
btrfs_log_inode_parent() it calls btrfs_log_all_parents(), since
inode X has a last_unlink_trans value of N, set at in step 1;
8) At btrfs_log_all_parents() we search for all parent directories of
inode X using the commit root, so we find directories A and B and log
them. Bu when logging direct A, we don't have a dir index item for
inode Y anymore, neither the old name "A/bar" nor for the new name
"A/baz" since the rename has deleted the old name but has not yet
inserted the new name - task A hasn't called yet btrfs_add_link() to
do that.
Note that logging directory A doesn't fallback to a transaction
commit because its last_unlink_trans has a lower value than the
current transaction's id (see step 4);
9) Task B finishes logging directories A and B and gets back to
btrfs_sync_file() where it calls btrfs_sync_log() to persist the log
tree;
10) Task B successfully persisted the log tree, btrfs_sync_log() completed
with success, and a power failure happened.
We have a log tree without any directory entry for inode Y, so the
log replay code deletes the entry for inode Y, name "A/bar", from the
subvolume tree since it doesn't exist in the log tree and the log
tree is authorative for its index (we logged a BTRFS_DIR_LOG_INDEX_KEY
item that covers the index range for the dentry that corresponds to
"A/bar").
Since there's no other hard link for inode Y and the log replay code
deletes the name "A/bar", the file is lost.
The issue wouldn't happen if task B synced the log only after task A
called btrfs_log_new_name(), which would update the log with the new name
for inode Y ("A/bar").
Fix this by pinning the log root during renames before removing the old
directory entry, and unpinning after btrfs_log_new_name() is called.
Fixes: 259c4b96d7 ("btrfs: stop doing unnecessary log updates during a rename")
CC: stable@vger.kernel.org # 5.18+
Reviewed-by: Boris Burkov <boris@bur.io>
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>
[ Upstream commit 547e836661 ]
[BUG]
There is syzbot based reproducer that can crash the kernel, with the
following call trace: (With some debug output added)
DEBUG: rescue=ibadroots parsed
BTRFS: device fsid 14d642db-7b15-43e4-81e6-4b8fac6a25f8 devid 1 transid 8 /dev/loop0 (7:0) scanned by repro (1010)
BTRFS info (device loop0): first mount of filesystem 14d642db-7b15-43e4-81e6-4b8fac6a25f8
BTRFS info (device loop0): using blake2b (blake2b-256-generic) checksum algorithm
BTRFS info (device loop0): using free-space-tree
BTRFS warning (device loop0): checksum verify failed on logical 5312512 mirror 1 wanted 0xb043382657aede36608fd3386d6b001692ff406164733d94e2d9a180412c6003 found 0x810ceb2bacb7f0f9eb2bf3b2b15c02af867cb35ad450898169f3b1f0bd818651 level 0
DEBUG: read tree root path failed for tree csum, ret=-5
BTRFS warning (device loop0): checksum verify failed on logical 5328896 mirror 1 wanted 0x51be4e8b303da58e6340226815b70e3a93592dac3f30dd510c7517454de8567a found 0x51be4e8b303da58e634022a315b70e3a93592dac3f30dd510c7517454de8567a level 0
BTRFS warning (device loop0): checksum verify failed on logical 5292032 mirror 1 wanted 0x1924ccd683be9efc2fa98582ef58760e3848e9043db8649ee382681e220cdee4 found 0x0cb6184f6e8799d9f8cb335dccd1d1832da1071d12290dab3b85b587ecacca6e level 0
process 'repro' launched './file2' with NULL argv: empty string added
DEBUG: no csum root, idatacsums=0 ibadroots=134217728
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000041: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000208-0x000000000000020f]
CPU: 5 UID: 0 PID: 1010 Comm: repro Tainted: G OE 6.15.0-custom+ #249 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022
RIP: 0010:btrfs_lookup_csum+0x93/0x3d0 [btrfs]
Call Trace:
<TASK>
btrfs_lookup_bio_sums+0x47a/0xdf0 [btrfs]
btrfs_submit_bbio+0x43e/0x1a80 [btrfs]
submit_one_bio+0xde/0x160 [btrfs]
btrfs_readahead+0x498/0x6a0 [btrfs]
read_pages+0x1c3/0xb20
page_cache_ra_order+0x4b5/0xc20
filemap_get_pages+0x2d3/0x19e0
filemap_read+0x314/0xde0
__kernel_read+0x35b/0x900
bprm_execve+0x62e/0x1140
do_execveat_common.isra.0+0x3fc/0x520
__x64_sys_execveat+0xdc/0x130
do_syscall_64+0x54/0x1d0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
---[ end trace 0000000000000000 ]---
[CAUSE]
Firstly the fs has a corrupted csum tree root, thus to mount the fs we
have to go "ro,rescue=ibadroots" mount option.
Normally with that mount option, a bad csum tree root should set
BTRFS_FS_STATE_NO_DATA_CSUMS flag, so that any future data read will
ignore csum search.
But in this particular case, we have the following call trace that
caused NULL csum root, but not setting BTRFS_FS_STATE_NO_DATA_CSUMS:
load_global_roots_objectid():
ret = btrfs_search_slot();
/* Succeeded */
btrfs_item_key_to_cpu()
found = true;
/* We found the root item for csum tree. */
root = read_tree_root_path();
if (IS_ERR(root)) {
if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
/*
* Since we have rescue=ibadroots mount option,
* @ret is still 0.
*/
break;
if (!found || ret) {
/* @found is true, @ret is 0, error handling for csum
* tree is skipped.
*/
}
This means we completely skipped to set BTRFS_FS_STATE_NO_DATA_CSUMS if
the csum tree is corrupted, which results unexpected later csum lookup.
[FIX]
If read_tree_root_path() failed, always populate @ret to the error
number.
As at the end of the function, we need @ret to determine if we need to
do the extra error handling for csum tree.
Fixes: abed4aaae4 ("btrfs: track the csum, extent, and free space trees in a rb tree")
Reported-by: Zhiyu Zhang <zhiyuzhang999@gmail.com>
Reported-by: Longxing Li <coregee2000@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f2c19541e4 ]
When the bytenr doesn't match for a metadata tree block, we will report
it as an csum error, which is incorrect and should be reported as a
metadata error instead.
Fixes: a3ddbaebc7 ("btrfs: scrub: introduce a helper to verify one metadata block")
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: Sasha Levin <sashal@kernel.org>
[ Upstream commit ec1f3a207c ]
[BUG]
Since the migration to the new scrub_stripe interface, scrub no longer
updates the device stats when hitting an error, no matter if it's a read
or checksum mismatch error. E.g:
BTRFS info (device dm-2): scrub: started on devid 1
BTRFS error (device dm-2): unable to fixup (regular) error at logical 13631488 on dev /dev/mapper/test-scratch1 physical 13631488
BTRFS warning (device dm-2): checksum error at logical 13631488 on dev /dev/mapper/test-scratch1, physical 13631488, root 5, inode 257, offset 0, length 4096, links 1 (path: file)
BTRFS error (device dm-2): unable to fixup (regular) error at logical 13631488 on dev /dev/mapper/test-scratch1 physical 13631488
BTRFS warning (device dm-2): checksum error at logical 13631488 on dev /dev/mapper/test-scratch1, physical 13631488, root 5, inode 257, offset 0, length 4096, links 1 (path: file)
BTRFS info (device dm-2): scrub: finished on devid 1 with status: 0
Note there is no line showing the device stats error update.
[CAUSE]
In the migration to the new scrub_stripe interface, we no longer call
btrfs_dev_stat_inc_and_print().
[FIX]
- Introduce a new bitmap for metadata generation errors
* A new bitmap
@meta_gen_error_bitmap is introduced to record which blocks have
metadata generation mismatch errors.
* A new counter for that bitmap
@init_nr_meta_gen_errors, is also introduced to store the number of
generation mismatch errors that are found during the initial read.
This is for the error reporting at scrub_stripe_report_errors().
* New dedicated error message for unrepaired generation mismatches
* Update @meta_gen_error_bitmap if a transid mismatch is hit
- Add btrfs_dev_stat_inc_and_print() calls to the following call sites
* scrub_stripe_report_errors()
* scrub_write_endio()
This is only for the write errors.
This means there is a minor behavior change:
- The timing of device stats error message
Since we concentrate the error messages at
scrub_stripe_report_errors(), the device stats error messages will all
show up in one go, after the detailed scrub error messages:
BTRFS error (device dm-2): unable to fixup (regular) error at logical 13631488 on dev /dev/mapper/test-scratch1 physical 13631488
BTRFS warning (device dm-2): checksum error at logical 13631488 on dev /dev/mapper/test-scratch1, physical 13631488, root 5, inode 257, offset 0, length 4096, links 1 (path: file)
BTRFS error (device dm-2): unable to fixup (regular) error at logical 13631488 on dev /dev/mapper/test-scratch1 physical 13631488
BTRFS warning (device dm-2): checksum error at logical 13631488 on dev /dev/mapper/test-scratch1, physical 13631488, root 5, inode 257, offset 0, length 4096, links 1 (path: file)
BTRFS error (device dm-2): bdev /dev/mapper/test-scratch1 errs: wr 0, rd 0, flush 0, corrupt 1, gen 0
BTRFS error (device dm-2): bdev /dev/mapper/test-scratch1 errs: wr 0, rd 0, flush 0, corrupt 2, gen 0
Fixes: e02ee89baa ("btrfs: scrub: switch scrub_simple_mirror() to scrub_stripe infrastructure")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 3e74859ee3 upstream.
When we call btrfs_read_folio() to bring a folio uptodate, we unlock the
folio. The result of that is that a different thread can modify the
mapping (like remove it with invalidate) before we call folio_lock().
This results in an invalid page and we need to try again.
In particular, if we are relocating concurrently with aborting a
transaction, this can result in a crash like the following:
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: 0000 [#1] SMP
CPU: 76 PID: 1411631 Comm: kworker/u322:5
Workqueue: events_unbound btrfs_reclaim_bgs_work
RIP: 0010:set_page_extent_mapped+0x20/0xb0
RSP: 0018:ffffc900516a7be8 EFLAGS: 00010246
RAX: ffffea009e851d08 RBX: ffffea009e0b1880 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffc900516a7b90 RDI: ffffea009e0b1880
RBP: 0000000003573000 R08: 0000000000000001 R09: ffff88c07fd2f3f0
R10: 0000000000000000 R11: 0000194754b575be R12: 0000000003572000
R13: 0000000003572fff R14: 0000000000100cca R15: 0000000005582fff
FS: 0000000000000000(0000) GS:ffff88c07fd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000407d00f002 CR4: 00000000007706f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __die+0x78/0xc0
? page_fault_oops+0x2a8/0x3a0
? __switch_to+0x133/0x530
? wq_worker_running+0xa/0x40
? exc_page_fault+0x63/0x130
? asm_exc_page_fault+0x22/0x30
? set_page_extent_mapped+0x20/0xb0
relocate_file_extent_cluster+0x1a7/0x940
relocate_data_extent+0xaf/0x120
relocate_block_group+0x20f/0x480
btrfs_relocate_block_group+0x152/0x320
btrfs_relocate_chunk+0x3d/0x120
btrfs_reclaim_bgs_work+0x2ae/0x4e0
process_scheduled_works+0x184/0x370
worker_thread+0xc6/0x3e0
? blk_add_timer+0xb0/0xb0
kthread+0xae/0xe0
? flush_tlb_kernel_range+0x90/0x90
ret_from_fork+0x2f/0x40
? flush_tlb_kernel_range+0x90/0x90
ret_from_fork_asm+0x11/0x20
</TASK>
This occurs because cleanup_one_transaction() calls
destroy_delalloc_inodes() which calls invalidate_inode_pages2() which
takes the folio_lock before setting mapping to NULL. We fail to check
this, and subsequently call set_extent_mapping(), which assumes that
mapping != NULL (in fact it asserts that in debug mode)
Note that the "fixes" patch here is not the one that introduced the
race (the very first iteration of this code from 2009) but a more recent
change that made this particular crash happen in practice.
Fixes: e7f1326cc2 ("btrfs: set page extent mapped after read_folio in relocate_one_page")
CC: stable@vger.kernel.org # 6.1+
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: Zhaoyang Li <lizy04@hust.edu.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f95d186255 ]
[BUG]
When trying read-only scrub on a btrfs with rescue=idatacsums mount
option, it will crash with the following call trace:
BUG: kernel NULL pointer dereference, address: 0000000000000208
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
CPU: 1 UID: 0 PID: 835 Comm: btrfs Tainted: G O 6.15.0-rc3-custom+ #236 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022
RIP: 0010:btrfs_lookup_csums_bitmap+0x49/0x480 [btrfs]
Call Trace:
<TASK>
scrub_find_fill_first_stripe+0x35b/0x3d0 [btrfs]
scrub_simple_mirror+0x175/0x290 [btrfs]
scrub_stripe+0x5f7/0x6f0 [btrfs]
scrub_chunk+0x9a/0x150 [btrfs]
scrub_enumerate_chunks+0x333/0x660 [btrfs]
btrfs_scrub_dev+0x23e/0x600 [btrfs]
btrfs_ioctl+0x1dcf/0x2f80 [btrfs]
__x64_sys_ioctl+0x97/0xc0
do_syscall_64+0x4f/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e
[CAUSE]
Mount option "rescue=idatacsums" will completely skip loading the csum
tree, so that any data read will not find any data csum thus we will
ignore data checksum verification.
Normally call sites utilizing csum tree will check the fs state flag
NO_DATA_CSUMS bit, but unfortunately scrub does not check that bit at all.
This results in scrub to call btrfs_search_slot() on a NULL pointer
and triggered above crash.
[FIX]
Check both extent and csum tree root before doing any tree search.
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: Sasha Levin <sashal@kernel.org>
[ Upstream commit a77749b3e2 ]
When attempting to build a too long path we are currently returning
-ENOMEM, which is very odd and misleading. So update fs_path_ensure_buf()
to return -ENAMETOOLONG instead. Also, while at it, move the WARN_ON()
into the if statement's expression, as it makes it clear what is being
tested and also has the effect of adding 'unlikely' to the statement,
which allows the compiler to generate better code as this condition is
never expected to happen.
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: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1283b8c125 ]
At btrfs_reclaim_bgs_work(), we are grabbing a block group's zone unusable
bytes while not under the protection of the block group's spinlock, so
this can trigger race reports from KCSAN (or similar tools) since that
field is typically updated while holding the lock, such as at
__btrfs_add_free_space_zoned() for example.
Fix this by grabbing the zone unusable bytes while we are still in the
critical section holding the block group's spinlock, which is right above
where we are currently grabbing it.
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: Sasha Levin <sashal@kernel.org>
[ Upstream commit cda76788f8 ]
At close_ctree() after we have ran delayed iputs either explicitly through
calling btrfs_run_delayed_iputs() or later during the call to
btrfs_commit_super() or btrfs_error_commit_super(), we assert that the
delayed iputs list is empty.
We have (another) race where this assertion might fail because we have
queued an async write into the fs_info->workers workqueue. Here's how it
happens:
1) We are submitting a data bio for an inode that is not the data
relocation inode, so we call btrfs_wq_submit_bio();
2) btrfs_wq_submit_bio() submits a work for the fs_info->workers queue
that will run run_one_async_done();
3) We enter close_ctree(), flush several work queues except
fs_info->workers, explicitly run delayed iputs with a call to
btrfs_run_delayed_iputs() and then again shortly after by calling
btrfs_commit_super() or btrfs_error_commit_super(), which also run
delayed iputs;
4) run_one_async_done() is executed in the work queue, and because there
was an IO error (bio->bi_status is not 0) it calls btrfs_bio_end_io(),
which drops the final reference on the associated ordered extent by
calling btrfs_put_ordered_extent() - and that adds a delayed iput for
the inode;
5) At close_ctree() we find that after stopping the cleaner and
transaction kthreads the delayed iputs list is not empty, failing the
following assertion:
ASSERT(list_empty(&fs_info->delayed_iputs));
Fix this by flushing the fs_info->workers workqueue before running delayed
iputs at close_ctree().
David reported this when running generic/648, which exercises IO error
paths by using the DM error table.
Reported-by: David Sterba <dsterba@suse.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: Sasha Levin <sashal@kernel.org>
[ Upstream commit df94a342ef ]
[BUG]
Even after all the error fixes related the
"ASSERT(list_empty(&fs_info->delayed_iputs));" in close_ctree(), I can
still hit it reliably with my experimental 2K block size.
[CAUSE]
In my case, all the error is triggered after the fs is already in error
status.
I find the following call trace to be the cause of race:
Main thread | endio_write_workers
---------------------------------------------+---------------------------
close_ctree() |
|- btrfs_error_commit_super() |
| |- btrfs_cleanup_transaction() |
| | |- btrfs_destroy_all_ordered_extents() |
| | |- btrfs_wait_ordered_roots() |
| |- btrfs_run_delayed_iputs() |
| | btrfs_finish_ordered_io()
| | |- btrfs_put_ordered_extent()
| | |- btrfs_add_delayed_iput()
|- ASSERT(list_empty(delayed_iputs)) |
!!! Triggered !!!
The root cause is that, btrfs_wait_ordered_roots() only wait for
ordered extents to finish their IOs, not to wait for them to finish and
removed.
[FIX]
Since btrfs_error_commit_super() will flush and wait for all ordered
extents, it should be executed early, before we start flushing the
workqueues.
And since btrfs_error_commit_super() now runs early, there is no need to
run btrfs_run_delayed_iputs() inside it, so just remove the
btrfs_run_delayed_iputs() call from btrfs_error_commit_super().
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7ef3cbf17d ]
The inline function btrfs_is_testing() is hardcoded to return 0 if
CONFIG_BTRFS_FS_RUN_SANITY_TESTS is not set. Currently we're relying on
the compiler optimizing out the call to alloc_test_extent_buffer() in
btrfs_find_create_tree_block(), as it's not been defined (it's behind an
#ifdef).
Add a stub version of alloc_test_extent_buffer() to avoid linker errors
on non-standard optimization levels. This problem was seen on GCC 14
with -O0 and is helps to see symbols that would be otherwise optimized
out.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Mark Harmstone <maharmstone@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 895c6721d3 ]
Currently, the async discard machinery owns a ref to the block_group
when the block_group is queued on a discard list. However, to handle
races with discard cancellation and the discard workfn, we have a
specific logic to detect that the block_group is *currently* running in
the workfn, to protect the workfn's usage amidst cancellation.
As far as I can tell, this doesn't have any overt bugs (though
finish_discard_pass() and remove_from_discard_list() racing can have a
surprising outcome for the caller of remove_from_discard_list() in that
it is again added at the end).
But it is needlessly complicated to rely on locking and the nullity of
discard_ctl->block_group. Simplify this significantly by just taking a
refcount while we are in the workfn and unconditionally drop it in both
the remove and workfn paths, regardless of if they race.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 28cb13f29f upstream.
Instead of doing a BUG_ON() handle the error by returning -EUCLEAN,
aborting the transaction and logging an error message.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[Minor conflict resolved due to code context change.]
Signed-off-by: Jianqi Ren <jianqi.ren.cn@windriver.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit be3f1938d3 upstream.
In run_delalloc_nocow(), when the found btrfs_key's offset > cur_offset,
it indicates a gap between the current processing region and
the next file extent. The original code would directly jump to
the "must_cow" label, which increments the slot and forces a fallback
to COW. This behavior might skip an extent item and result in an
overestimated COW fallback range.
This patch modifies the logic so that when a gap is detected:
- If no COW range is already being recorded (cow_start is unset),
cow_start is set to cur_offset.
- cur_offset is then advanced to the beginning of the next extent.
- Instead of jumping to "must_cow", control flows directly to
"next_slot" so that the same extent item can be reexamined properly.
The change ensures that we accurately account for the extent gap and
avoid accidentally extending the range that needs to fallback to COW.
CC: stable@vger.kernel.org # 6.6+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Dave Chen <davechen@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit bc2dbc4983 ]
[BUG]
When running btrfs/004 with 4K fs block size and 64K page size,
sometimes fsstress workload can take 100% CPU for a while, but not long
enough to trigger a 120s hang warning.
[CAUSE]
When such 100% CPU usage happens, btrfs_punch_hole_lock_range() is
always in the call trace.
One example when this problem happens, the function
btrfs_punch_hole_lock_range() got the following parameters:
lock_start = 4096, lockend = 20469
Then we calculate @page_lockstart by rounding up lock_start to page
boundary, which is 64K (page size is 64K).
For @page_lockend, we round down the value towards page boundary, which
result 0. Then since we need to pass an inclusive end to
filemap_range_has_page(), we subtract 1 from the rounded down value,
resulting in (u64)-1.
In the above case, the range is inside the same page, and we do not even
need to call filemap_range_has_page(), not to mention to call it with
(u64)-1 at the end.
This behavior will cause btrfs_punch_hole_lock_range() to busy loop
waiting for irrelevant range to have its pages dropped.
[FIX]
Calculate @page_lockend by just rounding down @lockend, without
decreasing the value by one. So @page_lockend will no longer overflow.
Then exit early if @page_lockend is no larger than @page_lockstart.
As it means either the range is inside the same page, or the two pages
are adjacent already.
Finally only decrease @page_lockend when calling filemap_range_has_page().
Fixes: 0528476b6a ("btrfs: fix the filemap_range_has_page() call in btrfs_punch_hole_lock_range()")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 2b084d8205 upstream.
The dealloc flag may be cleared and the extent won't reach the disk in
cow_file_range when errors path. The reserved qgroup space is freed in
commit 30479f31d4 ("btrfs: fix qgroup reserve leaks in
cow_file_range"). However, the length of untouched region to free needs
to be adjusted with the correct remaining region size.
Fixes: 30479f31d4 ("btrfs: fix qgroup reserve leaks in cow_file_range")
CC: stable@vger.kernel.org # 6.11+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Haisu Wang <haisuwang@tencent.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 30479f31d4 upstream.
In the buffered write path, the dirty page owns the qgroup reserve until
it creates an ordered_extent.
Therefore, any errors that occur before the ordered_extent is created
must free that reservation, or else the space is leaked. The fstest
generic/475 exercises various IO error paths, and is able to trigger
errors in cow_file_range where we fail to get to allocating the ordered
extent. Note that because we *do* clear delalloc, we are likely to
remove the inode from the delalloc list, so the inodes/pages to not have
invalidate/launder called on them in the commit abort path.
This results in failures at the unmount stage of the test that look like:
BTRFS: error (device dm-8 state EA) in cleanup_transaction:2018: errno=-5 IO failure
BTRFS: error (device dm-8 state EA) in btrfs_replace_file_extents:2416: errno=-5 IO failure
BTRFS warning (device dm-8 state EA): qgroup 0/5 has unreleased space, type 0 rsv 28672
------------[ cut here ]------------
WARNING: CPU: 3 PID: 22588 at fs/btrfs/disk-io.c:4333 close_ctree+0x222/0x4d0 [btrfs]
Modules linked in: btrfs blake2b_generic libcrc32c xor zstd_compress raid6_pq
CPU: 3 PID: 22588 Comm: umount Kdump: loaded Tainted: G W 6.10.0-rc7-gab56fde445b8 #21
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014
RIP: 0010:close_ctree+0x222/0x4d0 [btrfs]
RSP: 0018:ffffb4465283be00 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffa1a1818e1000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffb4465283bbe0 RDI: ffffa1a19374fcb8
RBP: ffffa1a1818e13c0 R08: 0000000100028b16 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000003 R12: ffffa1a18ad7972c
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f9168312b80(0000) GS:ffffa1a4afcc0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f91683c9140 CR3: 000000010acaa000 CR4: 00000000000006f0
Call Trace:
<TASK>
? close_ctree+0x222/0x4d0 [btrfs]
? __warn.cold+0x8e/0xea
? close_ctree+0x222/0x4d0 [btrfs]
? report_bug+0xff/0x140
? handle_bug+0x3b/0x70
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? close_ctree+0x222/0x4d0 [btrfs]
generic_shutdown_super+0x70/0x160
kill_anon_super+0x11/0x40
btrfs_kill_super+0x11/0x20 [btrfs]
deactivate_locked_super+0x2e/0xa0
cleanup_mnt+0xb5/0x150
task_work_run+0x57/0x80
syscall_exit_to_user_mode+0x121/0x130
do_syscall_64+0xab/0x1a0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f916847a887
---[ end trace 0000000000000000 ]---
BTRFS error (device dm-8 state EA): qgroup reserved space leaked
Cases 2 and 3 in the out_reserve path both pertain to this type of leak
and must free the reserved qgroup data. Because it is already an error
path, I opted not to handle the possible errors in
btrfs_free_qgroup_data.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
[Minor conflict resolved due to code context change.]
Signed-off-by: Jianqi Ren <jianqi.ren.cn@windriver.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dc08c58696 upstream.
Currently, displaying the btrfs subvol mount option doesn't escape ','.
This makes parsing /proc/self/mounts and /proc/self/mountinfo
ambiguous for subvolume names that contain commas. The text after the
comma could be mistaken for another option (think "subvol=foo,ro", where
ro is actually part of the subvolumes name).
Replace the manual escape characters list with a call to
seq_show_option(). Thanks to Calvin Walton for suggesting this approach.
Fixes: c8d3fe028f ("Btrfs: show subvol= and subvolid= in /proc/mounts")
CC: stable@vger.kernel.org # 5.4+
Suggested-by: Calvin Walton <calvin.walton@kepstin.ca>
Signed-off-by: Johannes Kimmel <kernel@bareminimum.eu>
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 35fec1089e upstream.
If do_zone_finish() is called with a filesystem that has missing devices
(e.g. a RAID file system mounted in degraded mode) it is accessing the
btrfs_device::zone_info pointer, which will not be set if the device
in question is missing.
Check if the device is present (by checking if it has a valid block device
pointer associated) and if not, skip zone finishing for it.
Fixes: 4dcbb8ab31 ("btrfs: zoned: make zone finishing multi stripe capable")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.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 2bbc4a45e5 upstream.
If btrfs_zone_activate() is called with a filesystem that has missing
devices (e.g. a RAID file system mounted in degraded mode) it is accessing
the btrfs_device::zone_info pointer, which will not be set if the device in
question is missing.
Check if the device is present (by checking if it has a valid block
device pointer associated) and if not, skip zone activation for it.
Fixes: f9a912a3c4 ("btrfs: zoned: make zone activation multi stripe capable")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.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 4c782247b8 upstream.
At close_ctree() after we have ran delayed iputs either through explicitly
calling btrfs_run_delayed_iputs() or later during the call to
btrfs_commit_super() or btrfs_error_commit_super(), we assert that the
delayed iputs list is empty.
When we have compressed writes this assertion may fail because delayed
iputs may have been added to the list after we last ran delayed iputs.
This happens like this:
1) We have a compressed write bio executing;
2) We enter close_ctree() and flush the fs_info->endio_write_workers
queue which is the queue used for running ordered extent completion;
3) The compressed write bio finishes and enters
btrfs_finish_compressed_write_work(), where it calls
btrfs_finish_ordered_extent() which in turn calls
btrfs_queue_ordered_fn(), which queues a work item in the
fs_info->endio_write_workers queue that we have flushed before;
4) At close_ctree() we proceed, run all existing delayed iputs and
call btrfs_commit_super() (which also runs delayed iputs), but before
we run the following assertion below:
ASSERT(list_empty(&fs_info->delayed_iputs))
A delayed iput is added by the step below...
5) The ordered extent completion job queued in step 3 runs and results in
creating a delayed iput when dropping the last reference of the ordered
extent (a call to btrfs_put_ordered_extent() made from
btrfs_finish_one_ordered());
6) At this point the delayed iputs list is not empty, so the assertion at
close_ctree() fails.
Fix this by flushing the fs_info->compressed_write_workers queue at
close_ctree() before flushing the fs_info->endio_write_workers queue,
respecting the queue dependency as the later is responsible for the
execution of ordered extent completion.
CC: stable@vger.kernel.org # 5.15+
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 5eb178f373 upstream.
In walk_up_proc() we BUG_ON(ret) from btrfs_dec_ref(). This is
incorrect, we have proper error handling here, return the error.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Jianqi Ren <jianqi.ren.cn@windriver.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e03418abde upstream.
We previously would call btrfs_check_leaf() if we had the check
integrity code enabled, which meant that we could only run the extended
leaf checks if we had WRITTEN set on the header flags.
This leaves a gap in our checking, because we could end up with
corruption on disk where WRITTEN isn't set on the leaf, and then the
extended leaf checks don't get run which we rely on to validate all of
the item pointers to make sure we don't access memory outside of the
extent buffer.
However, since 732fab95ab ("btrfs: check-integrity: remove
CONFIG_BTRFS_FS_CHECK_INTEGRITY option") we no longer call
btrfs_check_leaf() from btrfs_mark_buffer_dirty(), which means we only
ever call it on blocks that are being written out, and thus have WRITTEN
set, or that are being read in, which should have WRITTEN set.
Add checks to make sure we have WRITTEN set appropriately, and then make
sure __btrfs_check_leaf() always does the item checking. This will
protect us from file systems that have been corrupted and no longer have
WRITTEN set on some of the blocks.
This was hit on a crafted image tweaking the WRITTEN bit and reported by
KASAN as out-of-bound access in the eb accessors. The example is a dir
item at the end of an eb.
[2.042] BTRFS warning (device loop1): bad eb member start: ptr 0x3fff start 30572544 member offset 16410 size 2
[2.040] general protection fault, probably for non-canonical address 0xe0009d1000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI
[2.537] KASAN: maybe wild-memory-access in range [0x0005088000000018-0x000508800000001f]
[2.729] CPU: 0 PID: 2587 Comm: mount Not tainted 6.8.2 #1
[2.729] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
[2.621] RIP: 0010:btrfs_get_16+0x34b/0x6d0
[2.621] RSP: 0018:ffff88810871fab8 EFLAGS: 00000206
[2.621] RAX: 0000a11000000003 RBX: ffff888104ff8720 RCX: ffff88811b2288c0
[2.621] RDX: dffffc0000000000 RSI: ffffffff81dd8aca RDI: ffff88810871f748
[2.621] RBP: 000000000000401a R08: 0000000000000001 R09: ffffed10210e3ee9
[2.621] R10: ffff88810871f74f R11: 205d323430333737 R12: 000000000000001a
[2.621] R13: 000508800000001a R14: 1ffff110210e3f5d R15: ffffffff850011e8
[2.621] FS: 00007f56ea275840(0000) GS:ffff88811b200000(0000) knlGS:0000000000000000
[2.621] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[2.621] CR2: 00007febd13b75c0 CR3: 000000010bb50000 CR4: 00000000000006f0
[2.621] Call Trace:
[2.621] <TASK>
[2.621] ? show_regs+0x74/0x80
[2.621] ? die_addr+0x46/0xc0
[2.621] ? exc_general_protection+0x161/0x2a0
[2.621] ? asm_exc_general_protection+0x26/0x30
[2.621] ? btrfs_get_16+0x33a/0x6d0
[2.621] ? btrfs_get_16+0x34b/0x6d0
[2.621] ? btrfs_get_16+0x33a/0x6d0
[2.621] ? __pfx_btrfs_get_16+0x10/0x10
[2.621] ? __pfx_mutex_unlock+0x10/0x10
[2.621] btrfs_match_dir_item_name+0x101/0x1a0
[2.621] btrfs_lookup_dir_item+0x1f3/0x280
[2.621] ? __pfx_btrfs_lookup_dir_item+0x10/0x10
[2.621] btrfs_get_tree+0xd25/0x1910
Reported-by: lei lu <llfamsec@gmail.com>
CC: stable@vger.kernel.org # 6.7+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ copy more details from report ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Jianqi Ren <jianqi.ren.cn@windriver.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit da2dccd745 upstream.
At btrfs_write_check() if our file's i_size is not sector size aligned and
we have a write that starts at an offset larger than the i_size that falls
within the same page of the i_size, then we end up not zeroing the file
range [i_size, write_offset).
The code is this:
start_pos = round_down(pos, fs_info->sectorsize);
oldsize = i_size_read(inode);
if (start_pos > oldsize) {
/* Expand hole size to cover write data, preventing empty gap */
loff_t end_pos = round_up(pos + count, fs_info->sectorsize);
ret = btrfs_cont_expand(BTRFS_I(inode), oldsize, end_pos);
if (ret)
return ret;
}
So if our file's i_size is 90269 bytes and a write at offset 90365 bytes
comes in, we get 'start_pos' set to 90112 bytes, which is less than the
i_size and therefore we don't zero out the range [90269, 90365) by
calling btrfs_cont_expand().
This is an old bug introduced in commit 9036c10208 ("Btrfs: update hole
handling v2"), from 2008, and the buggy code got moved around over the
years.
Fix this by discarding 'start_pos' and comparing against the write offset
('pos') without any alignment.
This bug was recently exposed by test case generic/363 which tests this
scenario by polluting ranges beyond EOF with an mmap write and than verify
that after a file increases we get zeroes for the range which is supposed
to be a hole and not what we wrote with the previous mmaped write.
We're only seeing this exposed now because generic/363 used to run only
on xfs until last Sunday's fstests update.
The test was failing like this:
$ ./check generic/363
FSTYP -- btrfs
PLATFORM -- Linux/x86_64 debian0 6.13.0-rc7-btrfs-next-185+ #17 SMP PREEMPT_DYNAMIC Mon Feb 3 12:28:46 WET 2025
MKFS_OPTIONS -- /dev/sdc
MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1
generic/363 0s ... [failed, exit status 1]- output mismatch (see /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad)
# --- tests/generic/363.out 2025-02-05 15:31:14.013646509 +0000
# +++ /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad 2025-02-05 17:25:33.112630781 +0000
@@ -1 +1,46 @@
QA output created by 363
+READ BAD DATA: offset = 0xdcad, size = 0xd921, fname = /home/fdmanana/btrfs-tests/dev/junk
+OFFSET GOOD BAD RANGE
+0x1609d 0x0000 0x3104 0x0
+operation# (mod 256) for the bad data may be 4
+0x1609e 0x0000 0x0472 0x1
+operation# (mod 256) for the bad data may be 4
...
(Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/generic/363.out /home/fdmanana/git/hub/xfstests/results//generic/363.out.bad' to see the entire diff)
Ran: generic/363
Failures: generic/363
Failed 1 of 1 tests
Fixes: 9036c10208 ("Btrfs: update hole handling v2")
CC: stable@vger.kernel.org
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 2c8507c63f upstream.
This commit re-attempts the backport of the change to the linux-6.6.y
branch. Commit 6e1a822593 ("btrfs: avoid monopolizing a core when
activating a swap file") on this branch was reverted.
During swap activation we iterate over the extents of a file and we can
have many thousands of them, so we can end up in a busy loop monopolizing
a core. Avoid this by doing a voluntary reschedule after processing each
extent.
CC: stable@vger.kernel.org # 5.4+
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: Koichiro Den <koichiro.den@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 6e1a822593.
The backport for linux-6.6.y, commit 6e1a822593 ("btrfs: avoid
monopolizing a core when activating a swap file"), inserted
cond_resched() in the wrong location.
Revert it now; a subsequent commit will re-backport the original patch.
Fixes: 6e1a822593 ("btrfs: avoid monopolizing a core when activating a swap file") # linux-6.6.y
Signed-off-by: Koichiro Den <koichiro.den@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6a4730b325 ]
This BUG_ON is meant to catch backref cache problems, but these can
arise from either bugs in the backref cache or corruption in the extent
tree. Fix it to be a proper error.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5324c4e10e ]
A data race occurs when the function `insert_ordered_extent_file_extent()`
and the function `btrfs_inode_safe_disk_i_size_write()` are executed
concurrently. The function `insert_ordered_extent_file_extent()` is not
locked when reading inode->disk_i_size, causing
`btrfs_inode_safe_disk_i_size_write()` to cause data competition when
writing inode->disk_i_size, thus affecting the value of `modify_tree`.
The specific call stack that appears during testing is as follows:
============DATA_RACE============
btrfs_drop_extents+0x89a/0xa060 [btrfs]
insert_reserved_file_extent+0xb54/0x2960 [btrfs]
insert_ordered_extent_file_extent+0xff5/0x1760 [btrfs]
btrfs_finish_one_ordered+0x1b85/0x36a0 [btrfs]
btrfs_finish_ordered_io+0x37/0x60 [btrfs]
finish_ordered_fn+0x3e/0x50 [btrfs]
btrfs_work_helper+0x9c9/0x27a0 [btrfs]
process_scheduled_works+0x716/0xf10
worker_thread+0xb6a/0x1190
kthread+0x292/0x330
ret_from_fork+0x4d/0x80
ret_from_fork_asm+0x1a/0x30
============OTHER_INFO============
btrfs_inode_safe_disk_i_size_write+0x4ec/0x600 [btrfs]
btrfs_finish_one_ordered+0x24c7/0x36a0 [btrfs]
btrfs_finish_ordered_io+0x37/0x60 [btrfs]
finish_ordered_fn+0x3e/0x50 [btrfs]
btrfs_work_helper+0x9c9/0x27a0 [btrfs]
process_scheduled_works+0x716/0xf10
worker_thread+0xb6a/0x1190
kthread+0x292/0x330
ret_from_fork+0x4d/0x80
ret_from_fork_asm+0x1a/0x30
=================================
The main purpose of the check of the inode's disk_i_size is to avoid
taking write locks on a btree path when we have a write at or beyond
EOF, since in these cases we don't expect to find extent items in the
root to drop. However if we end up taking write locks due to a data
race on disk_i_size, everything is still correct, we only add extra
lock contention on the tree in case there's concurrency from other tasks.
If the race causes us to not take write locks when we actually need them,
then everything is functionally correct as well, since if we find out we
have extent items to drop and we took read locks (modify_tree set to 0),
we release the path and retry again with write locks.
Since this data race does not affect the correctness of the function,
it is a harmless data race, use data_race() to check inode->disk_i_size.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Hao-ran Zheng <zhenghaoran154@gmail.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: Sasha Levin <sashal@kernel.org>
commit d0f038104f upstream.
There is a recent ML report that mounting a large fs backed by hardware
RAID56 controller (with one device missing) took too much time, and
systemd seems to kill the mount attempt.
In that case, the only error message is:
BTRFS error (device sdj): open_ctree failed
There is no reason on why the failure happened, making it very hard to
understand the reason.
At least output the error number (in the particular case it should be
-EINTR) to provide some clue.
Link: https://lore.kernel.org/linux-btrfs/9b9c4d2810abcca2f9f76e32220ed9a90febb235.camel@scientia.org/
Reported-by: Christoph Anton Mitterer <calestyo@scientia.org>
Cc: stable@vger.kernel.org
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>
[ Upstream commit 6aecd91a5c ]
[BUG]
Syzbot reported a crash with the following call trace:
BTRFS info (device loop0): scrub: started on devid 1
BUG: kernel NULL pointer dereference, address: 0000000000000208
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0
Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 UID: 0 PID: 689 Comm: repro Kdump: loaded Tainted: G O 6.13.0-rc4-custom+ #206
Tainted: [O]=OOT_MODULE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022
RIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs]
Call Trace:
<TASK>
scrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs]
scrub_simple_mirror+0x175/0x260 [btrfs]
scrub_stripe+0x5d4/0x6c0 [btrfs]
scrub_chunk+0xbb/0x170 [btrfs]
scrub_enumerate_chunks+0x2f4/0x5f0 [btrfs]
btrfs_scrub_dev+0x240/0x600 [btrfs]
btrfs_ioctl+0x1dc8/0x2fa0 [btrfs]
? do_sys_openat2+0xa5/0xf0
__x64_sys_ioctl+0x97/0xc0
do_syscall_64+0x4f/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e
</TASK>
[CAUSE]
The reproducer is using a corrupted image where extent tree root is
corrupted, thus forcing to use "rescue=all,ro" mount option to mount the
image.
Then it triggered a scrub, but since scrub relies on extent tree to find
where the data/metadata extents are, scrub_find_fill_first_stripe()
relies on an non-empty extent root.
But unfortunately scrub_find_fill_first_stripe() doesn't really expect
an NULL pointer for extent root, it use extent_root to grab fs_info and
triggered a NULL pointer dereference.
[FIX]
Add an extra check for a valid extent root at the beginning of
scrub_find_fill_first_stripe().
The new error path is introduced by 42437a6386 ("btrfs: introduce
mount option rescue=ignorebadroots"), but that's pretty old, and later
commit b979547513 ("btrfs: scrub: introduce helper to find and fill
sector info for a scrub_stripe") changed how we do scrub.
So for kernels older than 6.6, the fix will need manual backport.
Reported-by: syzbot+339e9dbe3a2ca419b85d@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/67756935.050a0220.25abdd.0a12.GAE@google.com/
Fixes: 42437a6386 ("btrfs: introduce mount option rescue=ignorebadroots")
Reviewed-by: Anand Jain <anand.jain@oracle.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: Sasha Levin <sashal@kernel.org>
commit 05b36b04d7 upstream.
Shinichiro reported the following use-after free that sometimes is
happening in our CI system when running fstests' btrfs/284 on a TCMU
runner device:
BUG: KASAN: slab-use-after-free in lock_release+0x708/0x780
Read of size 8 at addr ffff888106a83f18 by task kworker/u80:6/219
CPU: 8 UID: 0 PID: 219 Comm: kworker/u80:6 Not tainted 6.12.0-rc6-kts+ #15
Hardware name: Supermicro Super Server/X11SPi-TF, BIOS 3.3 02/21/2020
Workqueue: btrfs-endio btrfs_end_bio_work [btrfs]
Call Trace:
<TASK>
dump_stack_lvl+0x6e/0xa0
? lock_release+0x708/0x780
print_report+0x174/0x505
? lock_release+0x708/0x780
? __virt_addr_valid+0x224/0x410
? lock_release+0x708/0x780
kasan_report+0xda/0x1b0
? lock_release+0x708/0x780
? __wake_up+0x44/0x60
lock_release+0x708/0x780
? __pfx_lock_release+0x10/0x10
? __pfx_do_raw_spin_lock+0x10/0x10
? lock_is_held_type+0x9a/0x110
_raw_spin_unlock_irqrestore+0x1f/0x60
__wake_up+0x44/0x60
btrfs_encoded_read_endio+0x14b/0x190 [btrfs]
btrfs_check_read_bio+0x8d9/0x1360 [btrfs]
? lock_release+0x1b0/0x780
? trace_lock_acquire+0x12f/0x1a0
? __pfx_btrfs_check_read_bio+0x10/0x10 [btrfs]
? process_one_work+0x7e3/0x1460
? lock_acquire+0x31/0xc0
? process_one_work+0x7e3/0x1460
process_one_work+0x85c/0x1460
? __pfx_process_one_work+0x10/0x10
? assign_work+0x16c/0x240
worker_thread+0x5e6/0xfc0
? __pfx_worker_thread+0x10/0x10
kthread+0x2c3/0x3a0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x31/0x70
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Allocated by task 3661:
kasan_save_stack+0x30/0x50
kasan_save_track+0x14/0x30
__kasan_kmalloc+0xaa/0xb0
btrfs_encoded_read_regular_fill_pages+0x16c/0x6d0 [btrfs]
send_extent_data+0xf0f/0x24a0 [btrfs]
process_extent+0x48a/0x1830 [btrfs]
changed_cb+0x178b/0x2ea0 [btrfs]
btrfs_ioctl_send+0x3bf9/0x5c20 [btrfs]
_btrfs_ioctl_send+0x117/0x330 [btrfs]
btrfs_ioctl+0x184a/0x60a0 [btrfs]
__x64_sys_ioctl+0x12e/0x1a0
do_syscall_64+0x95/0x180
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Freed by task 3661:
kasan_save_stack+0x30/0x50
kasan_save_track+0x14/0x30
kasan_save_free_info+0x3b/0x70
__kasan_slab_free+0x4f/0x70
kfree+0x143/0x490
btrfs_encoded_read_regular_fill_pages+0x531/0x6d0 [btrfs]
send_extent_data+0xf0f/0x24a0 [btrfs]
process_extent+0x48a/0x1830 [btrfs]
changed_cb+0x178b/0x2ea0 [btrfs]
btrfs_ioctl_send+0x3bf9/0x5c20 [btrfs]
_btrfs_ioctl_send+0x117/0x330 [btrfs]
btrfs_ioctl+0x184a/0x60a0 [btrfs]
__x64_sys_ioctl+0x12e/0x1a0
do_syscall_64+0x95/0x180
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The buggy address belongs to the object at ffff888106a83f00
which belongs to the cache kmalloc-rnd-07-96 of size 96
The buggy address is located 24 bytes inside of
freed 96-byte region [ffff888106a83f00, ffff888106a83f60)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888106a83800 pfn:0x106a83
flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff)
page_type: f5(slab)
raw: 0017ffffc0000000 ffff888100053680 ffffea0004917200 0000000000000004
raw: ffff888106a83800 0000000080200019 00000001f5000000 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff888106a83e00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff888106a83e80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff888106a83f00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
^
ffff888106a83f80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff888106a84000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
Further analyzing the trace and the crash dump's vmcore file shows that
the wake_up() call in btrfs_encoded_read_endio() is calling wake_up() on
the wait_queue that is in the private data passed to the end_io handler.
Commit 4ff47df40447 ("btrfs: move priv off stack in
btrfs_encoded_read_regular_fill_pages()") moved 'struct
btrfs_encoded_read_private' off the stack.
Before that commit one can see a corruption of the private data when
analyzing the vmcore after a crash:
*(struct btrfs_encoded_read_private *)0xffff88815626eec8 = {
.wait = (wait_queue_head_t){
.lock = (spinlock_t){
.rlock = (struct raw_spinlock){
.raw_lock = (arch_spinlock_t){
.val = (atomic_t){
.counter = (int)-2005885696,
},
.locked = (u8)0,
.pending = (u8)157,
.locked_pending = (u16)40192,
.tail = (u16)34928,
},
.magic = (unsigned int)536325682,
.owner_cpu = (unsigned int)29,
.owner = (void *)__SCT__tp_func_btrfs_transaction_commit+0x0 = 0x0,
.dep_map = (struct lockdep_map){
.key = (struct lock_class_key *)0xffff8881575a3b6c,
.class_cache = (struct lock_class *[2]){ 0xffff8882a71985c0, 0xffffea00066f5d40 },
.name = (const char *)0xffff88815626f100 = "",
.wait_type_outer = (u8)37,
.wait_type_inner = (u8)178,
.lock_type = (u8)154,
},
},
.__padding = (u8 [24]){ 0, 157, 112, 136, 50, 174, 247, 31, 29 },
.dep_map = (struct lockdep_map){
.key = (struct lock_class_key *)0xffff8881575a3b6c,
.class_cache = (struct lock_class *[2]){ 0xffff8882a71985c0, 0xffffea00066f5d40 },
.name = (const char *)0xffff88815626f100 = "",
.wait_type_outer = (u8)37,
.wait_type_inner = (u8)178,
.lock_type = (u8)154,
},
},
.head = (struct list_head){
.next = (struct list_head *)0x112cca,
.prev = (struct list_head *)0x47,
},
},
.pending = (atomic_t){
.counter = (int)-1491499288,
},
.status = (blk_status_t)130,
}
Here we can see several indicators of in-memory data corruption, e.g. the
large negative atomic values of ->pending or
->wait->lock->rlock->raw_lock->val, as well as the bogus spinlock magic
0x1ff7ae32 (decimal 536325682 above) instead of 0xdead4ead or the bogus
pointer values for ->wait->head.
To fix this, change atomic_dec_return() to atomic_dec_and_test() to fix the
corruption, as atomic_dec_return() is defined as two instructions on
x86_64, whereas atomic_dec_and_test() is defined as a single atomic
operation. This can lead to a situation where counter value is already
decremented but the if statement in btrfs_encoded_read_endio() is not
completely processed, i.e. the 0 test has not completed. If another thread
continues executing btrfs_encoded_read_regular_fill_pages() the
atomic_dec_return() there can see an already updated ->pending counter and
continues by freeing the private data. Continuing in the endio handler the
test for 0 succeeds and the wait_queue is woken up, resulting in a
use-after-free.
Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Suggested-by: Damien Le Moal <Damien.LeMoal@wdc.com>
Fixes: 1881fba89b ("btrfs: add BTRFS_IOC_ENCODED_READ ioctl")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alva Lan <alvalan9@foxmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 44f52bbe96 ]
When a COWing a tree block, at btrfs_cow_block(), and we have the
tracepoint trace_btrfs_cow_block() enabled and preemption is also enabled
(CONFIG_PREEMPT=y), we can trigger a use-after-free in the COWed extent
buffer while inside the tracepoint code. This is because in some paths
that call btrfs_cow_block(), such as btrfs_search_slot(), we are holding
the last reference on the extent buffer @buf so btrfs_force_cow_block()
drops the last reference on the @buf extent buffer when it calls
free_extent_buffer_stale(buf), which schedules the release of the extent
buffer with RCU. This means that if we are on a kernel with preemption,
the current task may be preempted before calling trace_btrfs_cow_block()
and the extent buffer already released by the time trace_btrfs_cow_block()
is called, resulting in a use-after-free.
Fix this by moving the trace_btrfs_cow_block() from btrfs_cow_block() to
btrfs_force_cow_block() before the COWed extent buffer is freed.
This also has a side effect of invoking the tracepoint in the tree defrag
code, at defrag.c:btrfs_realloc_node(), since btrfs_force_cow_block() is
called there, but this is fine and it was actually missing there.
Reported-by: syzbot+8517da8635307182c8a5@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/6759a9b9.050a0220.1ac542.000d.GAE@google.com/
CC: stable@vger.kernel.org # 5.4+
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: Sasha Levin <sashal@kernel.org>
[ Upstream commit 95f93bc4cb ]
Rename and export __btrfs_cow_block() as btrfs_force_cow_block(). This is
to allow to move defrag specific code out of ctree.c and into defrag.c in
one of the next patches.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 44f52bbe96 ("btrfs: fix use-after-free when COWing tree bock and tracing is enabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit fca432e73d upstream.
The following sysfs entries are reading super block member directly,
which can have a different endian and cause wrong values:
- sys/fs/btrfs/<uuid>/nodesize
- sys/fs/btrfs/<uuid>/sectorsize
- sys/fs/btrfs/<uuid>/clone_alignment
Thankfully those values (nodesize and sectorsize) are always aligned
inside the btrfs_super_block, so it won't trigger unaligned read errors,
just endian problems.
Fix them by using the native cached members instead.
Fixes: df93589a17 ("btrfs: export more from FS_INFO to sysfs")
CC: stable@vger.kernel.org
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
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>
Filipe Manana