commit 518837e650 upstream.
When an incremental send finds an extent that is shared, it checks which
file extent items in the range refer to that extent, and for those it
emits clone operations, while for others it emits regular write operations
to avoid corruption at the destination (as described and fixed by commit
d906d49fc5 ("Btrfs: send, fix file corruption due to incorrect cloning
operations")).
However when the root we are cloning from is the send root, we are cloning
from the inode currently being processed and the source file range has
several extent items that partially point to the desired extent, with an
offset smaller than the offset in the file extent item for the range we
want to clone into, it can cause the algorithm to issue a clone operation
that starts at the current eof of the file being processed in the receiver
side, in which case the receiver will fail, with EINVAL, when attempting
to execute the clone operation.
Example reproducer:
$ cat test-send-clone.sh
#!/bin/bash
DEV=/dev/sdi
MNT=/mnt/sdi
mkfs.btrfs -f $DEV >/dev/null
mount $DEV $MNT
# Create our test file with a single and large extent (1M) and with
# different content for different file ranges that will be reflinked
# later.
xfs_io -f \
-c "pwrite -S 0xab 0 128K" \
-c "pwrite -S 0xcd 128K 128K" \
-c "pwrite -S 0xef 256K 256K" \
-c "pwrite -S 0x1a 512K 512K" \
$MNT/foobar
btrfs subvolume snapshot -r $MNT $MNT/snap1
btrfs send -f /tmp/snap1.send $MNT/snap1
# Now do a series of changes to our file such that we end up with
# different parts of the extent reflinked into different file offsets
# and we overwrite a large part of the extent too, so no file extent
# items refer to that part that was overwritten. This used to confuse
# the algorithm used by the kernel to figure out which file ranges to
# clone, making it attempt to clone from a source range starting at
# the current eof of the file, resulting in the receiver to fail since
# it is an invalid clone operation.
#
xfs_io -c "reflink $MNT/foobar 64K 1M 960K" \
-c "reflink $MNT/foobar 0K 512K 256K" \
-c "reflink $MNT/foobar 512K 128K 256K" \
-c "pwrite -S 0x73 384K 640K" \
$MNT/foobar
btrfs subvolume snapshot -r $MNT $MNT/snap2
btrfs send -f /tmp/snap2.send -p $MNT/snap1 $MNT/snap2
echo -e "\nFile digest in the original filesystem:"
md5sum $MNT/snap2/foobar
# Now unmount the filesystem, create a new one, mount it and try to
# apply both send streams to recreate both snapshots.
umount $DEV
mkfs.btrfs -f $DEV >/dev/null
mount $DEV $MNT
btrfs receive -f /tmp/snap1.send $MNT
btrfs receive -f /tmp/snap2.send $MNT
# Must match what we got in the original filesystem of course.
echo -e "\nFile digest in the new filesystem:"
md5sum $MNT/snap2/foobar
umount $MNT
When running the reproducer, the incremental send operation fails due to
an invalid clone operation:
$ ./test-send-clone.sh
wrote 131072/131072 bytes at offset 0
128 KiB, 32 ops; 0.0015 sec (80.906 MiB/sec and 20711.9741 ops/sec)
wrote 131072/131072 bytes at offset 131072
128 KiB, 32 ops; 0.0013 sec (90.514 MiB/sec and 23171.6148 ops/sec)
wrote 262144/262144 bytes at offset 262144
256 KiB, 64 ops; 0.0025 sec (98.270 MiB/sec and 25157.2327 ops/sec)
wrote 524288/524288 bytes at offset 524288
512 KiB, 128 ops; 0.0052 sec (95.730 MiB/sec and 24506.9883 ops/sec)
Create a readonly snapshot of '/mnt/sdi' in '/mnt/sdi/snap1'
At subvol /mnt/sdi/snap1
linked 983040/983040 bytes at offset 1048576
960 KiB, 1 ops; 0.0006 sec (1.419 GiB/sec and 1550.3876 ops/sec)
linked 262144/262144 bytes at offset 524288
256 KiB, 1 ops; 0.0020 sec (120.192 MiB/sec and 480.7692 ops/sec)
linked 262144/262144 bytes at offset 131072
256 KiB, 1 ops; 0.0018 sec (133.833 MiB/sec and 535.3319 ops/sec)
wrote 655360/655360 bytes at offset 393216
640 KiB, 160 ops; 0.0093 sec (66.781 MiB/sec and 17095.8436 ops/sec)
Create a readonly snapshot of '/mnt/sdi' in '/mnt/sdi/snap2'
At subvol /mnt/sdi/snap2
File digest in the original filesystem:
9c13c61cb0b9f5abf45344375cb04dfa /mnt/sdi/snap2/foobar
At subvol snap1
At snapshot snap2
ERROR: failed to clone extents to foobar: Invalid argument
File digest in the new filesystem:
132f0396da8f48d2e667196bff882cfc /mnt/sdi/snap2/foobar
The clone operation is invalid because its source range starts at the
current eof of the file in the receiver, causing the receiver to get
an EINVAL error from the clone operation when attempting it.
For the example above, what happens is the following:
1) When processing the extent at file offset 1M, the algorithm checks that
the extent is shared and can be (fully or partially) found at file
offset 0.
At this point the file has a size (and eof) of 1M at the receiver;
2) It finds that our extent item at file offset 1M has a data offset of
64K and, since the file extent item at file offset 0 has a data offset
of 0, it issues a clone operation, from the same file and root, that
has a source range offset of 64K, destination offset of 1M and a length
of 64K, since the extent item at file offset 0 refers only to the first
128K of the shared extent.
After this clone operation, the file size (and eof) at the receiver is
increased from 1M to 1088K (1M + 64K);
3) Now there's still 896K (960K - 64K) of data left to clone or write, so
it checks for the next file extent item, which starts at file offset
128K. This file extent item has a data offset of 0 and a length of
256K, so a clone operation with a source range offset of 256K, a
destination offset of 1088K (1M + 64K) and length of 128K is issued.
After this operation the file size (and eof) at the receiver increases
from 1088K to 1216K (1088K + 128K);
4) Now there's still 768K (896K - 128K) of data left to clone or write, so
it checks for the next file extent item, located at file offset 384K.
This file extent item points to a different extent, not the one we want
to clone, with a length of 640K. So we issue a write operation into the
file range 1216K (1088K + 128K, end of the last clone operation), with
a length of 640K and with a data matching the one we can find for that
range in send root.
After this operation, the file size (and eof) at the receiver increases
from 1216K to 1856K (1216K + 640K);
5) Now there's still 128K (768K - 640K) of data left to clone or write, so
we look into the file extent item, which is for file offset 1M and it
points to the extent we want to clone, with a data offset of 64K and a
length of 960K.
However this matches the file offset we started with, the start of the
range to clone into. So we can't for sure find any file extent item
from here onwards with the rest of the data we want to clone, yet we
proceed and since the file extent item points to the shared extent,
with a data offset of 64K, we issue a clone operation with a source
range starting at file offset 1856K, which matches the file extent
item's offset, 1M, plus the amount of data cloned and written so far,
which is 64K (step 2) + 128K (step 3) + 640K (step 4). This clone
operation is invalid since the source range offset matches the current
eof of the file in the receiver. We should have stopped looking for
extents to clone at this point and instead fallback to write, which
would simply the contain the data in the file range from 1856K to
1856K + 128K.
So fix this by stopping the loop that looks for file ranges to clone at
clone_range() when we reach the current eof of the file being processed,
if we are cloning from the same file and using the send root as the clone
root. This ensures any data not yet cloned will be sent to the receiver
through a write operation.
A test case for fstests will follow soon.
Reported-by: Massimo B. <massimo.b@gmx.net>
Link: https://lore.kernel.org/linux-btrfs/6ae34776e85912960a253a8327068a892998e685.camel@gmx.net/
Fixes: 11f2069c11 ("Btrfs: send, allow clone operations within the same file")
CC: stable@vger.kernel.org # 5.5+
Reviewed-by: Josef Bacik <josef@toxicpanda.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 34d1eb0e59 upstream.
If we fail to update a block group item in the loop we'll break, however
we'll do btrfs_run_delayed_refs and lose our error value in ret, and
thus not clean up properly. Fix this by only running the delayed refs
if there was no failure.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 18d3bff411 upstream.
This was partially fixed by f3e3d9cc35 ("btrfs: avoid possible signal
interruption of btrfs_drop_snapshot() on relocation tree"), however it
missed a spot when we restart a trans handle because we need to end the
transaction. The fix is the same, simply use btrfs_join_transaction()
instead of btrfs_start_transaction() when deleting reloc roots.
Fixes: f3e3d9cc35 ("btrfs: avoid possible signal interruption of btrfs_drop_snapshot() on relocation tree")
CC: stable@vger.kernel.org # 5.4+
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 29b665cc51 upstream.
Some extent io trees are initialized with NULL private member (e.g.
btrfs_device::alloc_state and btrfs_fs_info::excluded_extents).
Dereference of a NULL tree->private as inode pointer will cause panic.
Pass tree->fs_info as it's known to be valid in all cases.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=208929
Fixes: 05912a3c04 ("btrfs: drop extent_io_ops::tree_fs_info callback")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Su Yue <l@damenly.su>
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 0b3f407e67 upstream.
When doing an incremental send, if we have a new inode that happens to
have the same number that an old directory inode had in the base snapshot
and that old directory has a pending rmdir operation, we end up computing
a wrong path for the new inode, causing the receiver to fail.
Example reproducer:
$ cat test-send-rmdir.sh
#!/bin/bash
DEV=/dev/sdi
MNT=/mnt/sdi
mkfs.btrfs -f $DEV >/dev/null
mount $DEV $MNT
mkdir $MNT/dir
touch $MNT/dir/file1
touch $MNT/dir/file2
touch $MNT/dir/file3
# Filesystem looks like:
#
# . (ino 256)
# |----- dir/ (ino 257)
# |----- file1 (ino 258)
# |----- file2 (ino 259)
# |----- file3 (ino 260)
#
btrfs subvolume snapshot -r $MNT $MNT/snap1
btrfs send -f /tmp/snap1.send $MNT/snap1
# Now remove our directory and all its files.
rm -fr $MNT/dir
# Unmount the filesystem and mount it again. This is to ensure that
# the next inode that is created ends up with the same inode number
# that our directory "dir" had, 257, which is the first free "objectid"
# available after mounting again the filesystem.
umount $MNT
mount $DEV $MNT
# Now create a new file (it could be a directory as well).
touch $MNT/newfile
# Filesystem now looks like:
#
# . (ino 256)
# |----- newfile (ino 257)
#
btrfs subvolume snapshot -r $MNT $MNT/snap2
btrfs send -f /tmp/snap2.send -p $MNT/snap1 $MNT/snap2
# Now unmount the filesystem, create a new one, mount it and try to apply
# both send streams to recreate both snapshots.
umount $DEV
mkfs.btrfs -f $DEV >/dev/null
mount $DEV $MNT
btrfs receive -f /tmp/snap1.send $MNT
btrfs receive -f /tmp/snap2.send $MNT
umount $MNT
When running the test, the receive operation for the incremental stream
fails:
$ ./test-send-rmdir.sh
Create a readonly snapshot of '/mnt/sdi' in '/mnt/sdi/snap1'
At subvol /mnt/sdi/snap1
Create a readonly snapshot of '/mnt/sdi' in '/mnt/sdi/snap2'
At subvol /mnt/sdi/snap2
At subvol snap1
At snapshot snap2
ERROR: chown o257-9-0 failed: No such file or directory
So fix this by tracking directories that have a pending rmdir by inode
number and generation number, instead of only inode number.
A test case for fstests follows soon.
Reported-by: Massimo B. <massimo.b@gmx.net>
Tested-by: Massimo B. <massimo.b@gmx.net>
Link: https://lore.kernel.org/linux-btrfs/6ae34776e85912960a253a8327068a892998e685.camel@gmx.net/
CC: stable@vger.kernel.org # 4.19+
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 7f458a3873 ]
When defragmenting we skip ranges that have holes or inline extents, so that
we don't do unnecessary IO and waste space. We do this check when calling
should_defrag_range() at btrfs_defrag_file(). However we do it without
holding the inode's lock. The reason we do it like this is to avoid
blocking other tasks for too long, that possibly want to operate on other
file ranges, since after the call to should_defrag_range() and before
locking the inode, we trigger a synchronous page cache readahead. However
before we were able to lock the inode, some other task might have punched
a hole in our range, or we may now have an inline extent there, in which
case we should not set the range for defrag anymore since that would cause
unnecessary IO and make us waste space (i.e. allocating extents to contain
zeros for a hole).
So after we locked the inode and the range in the iotree, check again if
we have holes or an inline extent, and if we do, just skip the range.
I hit this while testing my next patch that fixes races when updating an
inode's number of bytes (subject "btrfs: update the number of bytes used
by an inode atomically"), and it depends on this change in order to work
correctly. Alternatively I could rework that other patch to detect holes
and flag their range with the 'new delalloc' bit, but this itself fixes
an efficiency problem due a race that from a functional point of view is
not harmful (it could be triggered with btrfs/062 from fstests).
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.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 c57dd1f2f6 upstream
[BUG]
The following script can lead to tons of beyond device boundary access:
mkfs.btrfs -f $dev -b 10G
mount $dev $mnt
trimfs $mnt
btrfs filesystem resize 1:-1G $mnt
trimfs $mnt
[CAUSE]
Since commit 929be17a9b ("btrfs: Switch btrfs_trim_free_extents to
find_first_clear_extent_bit"), we try to avoid trimming ranges that's
already trimmed.
So we check device->alloc_state by finding the first range which doesn't
have CHUNK_TRIMMED and CHUNK_ALLOCATED not set.
But if we shrunk the device, that bits are not cleared, thus we could
easily got a range starts beyond the shrunk device size.
This results the returned @start and @end are all beyond device size,
then we call "end = min(end, device->total_bytes -1);" making @end
smaller than device size.
Then finally we goes "len = end - start + 1", totally underflow the
result, and lead to the beyond-device-boundary access.
[FIX]
This patch will fix the problem in two ways:
- Clear CHUNK_TRIMMED | CHUNK_ALLOCATED bits when shrinking device
This is the root fix
- Add extra safety check when trimming free device extents
We check and warn if the returned range is already beyond current
device.
Link: https://github.com/kdave/btrfs-progs/issues/282
Fixes: 929be17a9b ("btrfs: Switch btrfs_trim_free_extents to find_first_clear_extent_bit")
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[sudip: adjust context and use extent_io.h]
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9076dbd5ee upstream.
While fixing up our ->last_byte_to_unpin locking I noticed that we will
shorten len based on ->last_byte_to_unpin if we're caching when we're
adding back the free space. This is correct for the free space, as we
cannot unpin more than ->last_byte_to_unpin, however we use len to
adjust the ->bytes_pinned counters and such, which need to track the
actual pinned usage. This could result in
WARN_ON(space_info->bytes_pinned) triggering at unmount time.
Fix this by using a local variable for the amount to add to free space
cache, and leave len untouched in this case.
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0697d9a610 upstream.
Syzbot reported a possible use-after-free when printing a duplicate device
warning device_list_add().
At this point it can happen that a btrfs_device::fs_info is not correctly
setup yet, so we're accessing stale data, when printing the warning
message using the btrfs_printk() wrappers.
==================================================================
BUG: KASAN: use-after-free in btrfs_printk+0x3eb/0x435 fs/btrfs/super.c:245
Read of size 8 at addr ffff8880878e06a8 by task syz-executor225/7068
CPU: 1 PID: 7068 Comm: syz-executor225 Not tainted 5.9.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1d6/0x29e lib/dump_stack.c:118
print_address_description+0x66/0x620 mm/kasan/report.c:383
__kasan_report mm/kasan/report.c:513 [inline]
kasan_report+0x132/0x1d0 mm/kasan/report.c:530
btrfs_printk+0x3eb/0x435 fs/btrfs/super.c:245
device_list_add+0x1a88/0x1d60 fs/btrfs/volumes.c:943
btrfs_scan_one_device+0x196/0x490 fs/btrfs/volumes.c:1359
btrfs_mount_root+0x48f/0xb60 fs/btrfs/super.c:1634
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x88/0x270 fs/super.c:1547
fc_mount fs/namespace.c:978 [inline]
vfs_kern_mount+0xc9/0x160 fs/namespace.c:1008
btrfs_mount+0x33c/0xae0 fs/btrfs/super.c:1732
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x88/0x270 fs/super.c:1547
do_new_mount fs/namespace.c:2875 [inline]
path_mount+0x179d/0x29e0 fs/namespace.c:3192
do_mount fs/namespace.c:3205 [inline]
__do_sys_mount fs/namespace.c:3413 [inline]
__se_sys_mount+0x126/0x180 fs/namespace.c:3390
do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x44840a
RSP: 002b:00007ffedfffd608 EFLAGS: 00000293 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffedfffd670 RCX: 000000000044840a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffedfffd630
RBP: 00007ffedfffd630 R08: 00007ffedfffd670 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000000001a
R13: 0000000000000004 R14: 0000000000000003 R15: 0000000000000003
Allocated by task 6945:
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_set_track mm/kasan/common.c:56 [inline]
__kasan_kmalloc+0x100/0x130 mm/kasan/common.c:461
kmalloc_node include/linux/slab.h:577 [inline]
kvmalloc_node+0x81/0x110 mm/util.c:574
kvmalloc include/linux/mm.h:757 [inline]
kvzalloc include/linux/mm.h:765 [inline]
btrfs_mount_root+0xd0/0xb60 fs/btrfs/super.c:1613
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x88/0x270 fs/super.c:1547
fc_mount fs/namespace.c:978 [inline]
vfs_kern_mount+0xc9/0x160 fs/namespace.c:1008
btrfs_mount+0x33c/0xae0 fs/btrfs/super.c:1732
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x88/0x270 fs/super.c:1547
do_new_mount fs/namespace.c:2875 [inline]
path_mount+0x179d/0x29e0 fs/namespace.c:3192
do_mount fs/namespace.c:3205 [inline]
__do_sys_mount fs/namespace.c:3413 [inline]
__se_sys_mount+0x126/0x180 fs/namespace.c:3390
do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Freed by task 6945:
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_set_track+0x3d/0x70 mm/kasan/common.c:56
kasan_set_free_info+0x17/0x30 mm/kasan/generic.c:355
__kasan_slab_free+0xdd/0x110 mm/kasan/common.c:422
__cache_free mm/slab.c:3418 [inline]
kfree+0x113/0x200 mm/slab.c:3756
deactivate_locked_super+0xa7/0xf0 fs/super.c:335
btrfs_mount_root+0x72b/0xb60 fs/btrfs/super.c:1678
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x88/0x270 fs/super.c:1547
fc_mount fs/namespace.c:978 [inline]
vfs_kern_mount+0xc9/0x160 fs/namespace.c:1008
btrfs_mount+0x33c/0xae0 fs/btrfs/super.c:1732
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x88/0x270 fs/super.c:1547
do_new_mount fs/namespace.c:2875 [inline]
path_mount+0x179d/0x29e0 fs/namespace.c:3192
do_mount fs/namespace.c:3205 [inline]
__do_sys_mount fs/namespace.c:3413 [inline]
__se_sys_mount+0x126/0x180 fs/namespace.c:3390
do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
The buggy address belongs to the object at ffff8880878e0000
which belongs to the cache kmalloc-16k of size 16384
The buggy address is located 1704 bytes inside of
16384-byte region [ffff8880878e0000, ffff8880878e4000)
The buggy address belongs to the page:
page:0000000060704f30 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x878e0
head:0000000060704f30 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea00028e9a08 ffffea00021e3608 ffff8880aa440b00
raw: 0000000000000000 ffff8880878e0000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8880878e0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880878e0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880878e0680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880878e0700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880878e0780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
The syzkaller reproducer for this use-after-free crafts a filesystem image
and loop mounts it twice in a loop. The mount will fail as the crafted
image has an invalid chunk tree. When this happens btrfs_mount_root() will
call deactivate_locked_super(), which then cleans up fs_info and
fs_info::sb. If a second thread now adds the same block-device to the
filesystem, it will get detected as a duplicate device and
device_list_add() will reject the duplicate and print a warning. But as
the fs_info pointer passed in is non-NULL this will result in a
use-after-free.
Instead of printing possibly uninitialized or already freed memory in
btrfs_printk(), explicitly pass in a NULL fs_info so the printing of the
device name will be skipped altogether.
There was a slightly different approach discussed in
https://lore.kernel.org/linux-btrfs/20200114060920.4527-1-anand.jain@oracle.com/t/#u
Link: https://lore.kernel.org/linux-btrfs/000000000000c9e14b05afcc41ba@google.com
Reported-by: syzbot+582e66e5edf36a22c7b0@syzkaller.appspotmail.com
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Nikolay Borisov <nborisov@suse.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 6d06b0ad94 upstream.
There are sectorsize alignment checks that are reported but then
check_extent_data_ref continues. This was not intended, wrong alignment
is not a minor problem and we should return with error.
CC: stable@vger.kernel.org # 5.4+
Fixes: 0785a9aacf ("btrfs: tree-checker: Add EXTENT_DATA_REF check")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1a49a97df6 upstream.
There's a missing return statement after an error is found in the
root_item, this can cause further problems when a crafted image triggers
the error.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=210181
Fixes: 259ee7754b ("btrfs: tree-checker: Add ROOT_ITEM check")
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
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 a1fbc6750e upstream.
On 32-bit systems, this shift will overflow for files larger than 4GB as
start_index is unsigned long while the calls to btrfs_delalloc_*_space
expect u64.
CC: stable@vger.kernel.org # 4.4+
Fixes: df480633b8 ("btrfs: extent-tree: Switch to new delalloc space reserve and release")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Sterba <dsterba@suse.com>
[ define the variable instead of repeating the shift ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cf89af146b upstream.
If there is a device BTRFS_DEV_REPLACE_DEVID without the device replace
item, then it means the filesystem is inconsistent state. This is either
corruption or a crafted image. Fail the mount as this needs a closer
look what is actually wrong.
As of now if BTRFS_DEV_REPLACE_DEVID is present without the replace
item, in __btrfs_free_extra_devids() we determine that there is an
extra device, and free those extra devices but continue to mount the
device.
However, we were wrong in keeping tack of the rw_devices so the syzbot
testcase failed:
WARNING: CPU: 1 PID: 3612 at fs/btrfs/volumes.c:1166 close_fs_devices.part.0+0x607/0x800 fs/btrfs/volumes.c:1166
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 3612 Comm: syz-executor.2 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x198/0x1fd lib/dump_stack.c:118
panic+0x347/0x7c0 kernel/panic.c:231
__warn.cold+0x20/0x46 kernel/panic.c:600
report_bug+0x1bd/0x210 lib/bug.c:198
handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234
exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254
asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
RIP: 0010:close_fs_devices.part.0+0x607/0x800 fs/btrfs/volumes.c:1166
RSP: 0018:ffffc900091777e0 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffffffffffffffff RCX: ffffc9000c8b7000
RDX: 0000000000040000 RSI: ffffffff83097f47 RDI: 0000000000000007
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffff8880988a187f
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88809593a130
R13: ffff88809593a1ec R14: ffff8880988a1908 R15: ffff88809593a050
close_fs_devices fs/btrfs/volumes.c:1193 [inline]
btrfs_close_devices+0x95/0x1f0 fs/btrfs/volumes.c:1179
open_ctree+0x4984/0x4a2d fs/btrfs/disk-io.c:3434
btrfs_fill_super fs/btrfs/super.c:1316 [inline]
btrfs_mount_root.cold+0x14/0x165 fs/btrfs/super.c:1672
The fix here is, when we determine that there isn't a replace item
then fail the mount if there is a replace target device (devid 0).
CC: stable@vger.kernel.org # 4.19+
Reported-by: syzbot+4cfe71a4da060be47502@syzkaller.appspotmail.com
Signed-off-by: Anand Jain <anand.jain@oracle.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 468600c6ec upstream.
There is one error handling path that does not free ref, which may cause
a minor memory leak.
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current trace event always output result like this:
find_free_extent: root=2(EXTENT_TREE) len=16384 empty_size=0 flags=4(METADATA)
find_free_extent: root=2(EXTENT_TREE) len=16384 empty_size=0 flags=4(METADATA)
find_free_extent: root=2(EXTENT_TREE) len=8192 empty_size=0 flags=1(DATA)
find_free_extent: root=2(EXTENT_TREE) len=8192 empty_size=0 flags=1(DATA)
find_free_extent: root=2(EXTENT_TREE) len=4096 empty_size=0 flags=1(DATA)
find_free_extent: root=2(EXTENT_TREE) len=4096 empty_size=0 flags=1(DATA)
T's saying we're allocating data extent for EXTENT tree, which is not
even possible.
It's because we always use EXTENT tree as the owner for
trace_find_free_extent() without using the @root from
btrfs_reserve_extent().
This patch will change the parameter to use proper @root for
trace_find_free_extent():
Now it looks much better:
find_free_extent: root=5(FS_TREE) len=16384 empty_size=0 flags=36(METADATA|DUP)
find_free_extent: root=5(FS_TREE) len=8192 empty_size=0 flags=1(DATA)
find_free_extent: root=5(FS_TREE) len=16384 empty_size=0 flags=1(DATA)
find_free_extent: root=5(FS_TREE) len=4096 empty_size=0 flags=1(DATA)
find_free_extent: root=5(FS_TREE) len=8192 empty_size=0 flags=1(DATA)
find_free_extent: root=5(FS_TREE) len=16384 empty_size=0 flags=36(METADATA|DUP)
find_free_extent: root=7(CSUM_TREE) len=16384 empty_size=0 flags=36(METADATA|DUP)
find_free_extent: root=2(EXTENT_TREE) len=16384 empty_size=0 flags=36(METADATA|DUP)
find_free_extent: root=1(ROOT_TREE) len=16384 empty_size=0 flags=36(METADATA|DUP)
Reported-by: Hans van Kranenburg <hans@knorrie.org>
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
commit 66d204a16c upstream.
Very sporadically I had test case btrfs/069 from fstests hanging (for
years, it is not a recent regression), with the following traces in
dmesg/syslog:
[162301.160628] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg started
[162301.181196] BTRFS info (device sdc): scrub: finished on devid 4 with status: 0
[162301.287162] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg finished
[162513.513792] INFO: task btrfs-transacti:1356167 blocked for more than 120 seconds.
[162513.514318] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.514522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.514747] task:btrfs-transacti state:D stack: 0 pid:1356167 ppid: 2 flags:0x00004000
[162513.514751] Call Trace:
[162513.514761] __schedule+0x5ce/0xd00
[162513.514765] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.514771] schedule+0x46/0xf0
[162513.514844] wait_current_trans+0xde/0x140 [btrfs]
[162513.514850] ? finish_wait+0x90/0x90
[162513.514864] start_transaction+0x37c/0x5f0 [btrfs]
[162513.514879] transaction_kthread+0xa4/0x170 [btrfs]
[162513.514891] ? btrfs_cleanup_transaction+0x660/0x660 [btrfs]
[162513.514894] kthread+0x153/0x170
[162513.514897] ? kthread_stop+0x2c0/0x2c0
[162513.514902] ret_from_fork+0x22/0x30
[162513.514916] INFO: task fsstress:1356184 blocked for more than 120 seconds.
[162513.515192] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.515431] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.515680] task:fsstress state:D stack: 0 pid:1356184 ppid:1356177 flags:0x00004000
[162513.515682] Call Trace:
[162513.515688] __schedule+0x5ce/0xd00
[162513.515691] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.515697] schedule+0x46/0xf0
[162513.515712] wait_current_trans+0xde/0x140 [btrfs]
[162513.515716] ? finish_wait+0x90/0x90
[162513.515729] start_transaction+0x37c/0x5f0 [btrfs]
[162513.515743] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
[162513.515753] btrfs_sync_fs+0x61/0x1c0 [btrfs]
[162513.515758] ? __ia32_sys_fdatasync+0x20/0x20
[162513.515761] iterate_supers+0x87/0xf0
[162513.515765] ksys_sync+0x60/0xb0
[162513.515768] __do_sys_sync+0xa/0x10
[162513.515771] do_syscall_64+0x33/0x80
[162513.515774] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.515781] RIP: 0033:0x7f5238f50bd7
[162513.515782] Code: Bad RIP value.
[162513.515784] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
[162513.515786] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
[162513.515788] RDX: 00000000ffffffff RSI: 000000000daf0e74 RDI: 000000000000003a
[162513.515789] RBP: 0000000000000032 R08: 000000000000000a R09: 00007f5239019be0
[162513.515791] R10: fffffffffffff24f R11: 0000000000000206 R12: 000000000000003a
[162513.515792] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
[162513.515804] INFO: task fsstress:1356185 blocked for more than 120 seconds.
[162513.516064] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.516329] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.516617] task:fsstress state:D stack: 0 pid:1356185 ppid:1356177 flags:0x00000000
[162513.516620] Call Trace:
[162513.516625] __schedule+0x5ce/0xd00
[162513.516628] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.516634] schedule+0x46/0xf0
[162513.516647] wait_current_trans+0xde/0x140 [btrfs]
[162513.516650] ? finish_wait+0x90/0x90
[162513.516662] start_transaction+0x4d7/0x5f0 [btrfs]
[162513.516679] btrfs_setxattr_trans+0x3c/0x100 [btrfs]
[162513.516686] __vfs_setxattr+0x66/0x80
[162513.516691] __vfs_setxattr_noperm+0x70/0x200
[162513.516697] vfs_setxattr+0x6b/0x120
[162513.516703] setxattr+0x125/0x240
[162513.516709] ? lock_acquire+0xb1/0x480
[162513.516712] ? mnt_want_write+0x20/0x50
[162513.516721] ? rcu_read_lock_any_held+0x8e/0xb0
[162513.516723] ? preempt_count_add+0x49/0xa0
[162513.516725] ? __sb_start_write+0x19b/0x290
[162513.516727] ? preempt_count_add+0x49/0xa0
[162513.516732] path_setxattr+0xba/0xd0
[162513.516739] __x64_sys_setxattr+0x27/0x30
[162513.516741] do_syscall_64+0x33/0x80
[162513.516743] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.516745] RIP: 0033:0x7f5238f56d5a
[162513.516746] Code: Bad RIP value.
[162513.516748] RSP: 002b:00007fff67b97868 EFLAGS: 00000202 ORIG_RAX: 00000000000000bc
[162513.516750] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5238f56d5a
[162513.516751] RDX: 000055b1fbb0d5a0 RSI: 00007fff67b978a0 RDI: 000055b1fbb0d470
[162513.516753] RBP: 000055b1fbb0d5a0 R08: 0000000000000001 R09: 00007fff67b97700
[162513.516754] R10: 0000000000000004 R11: 0000000000000202 R12: 0000000000000004
[162513.516756] R13: 0000000000000024 R14: 0000000000000001 R15: 00007fff67b978a0
[162513.516767] INFO: task fsstress:1356196 blocked for more than 120 seconds.
[162513.517064] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.517365] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.517763] task:fsstress state:D stack: 0 pid:1356196 ppid:1356177 flags:0x00004000
[162513.517780] Call Trace:
[162513.517786] __schedule+0x5ce/0xd00
[162513.517789] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.517796] schedule+0x46/0xf0
[162513.517810] wait_current_trans+0xde/0x140 [btrfs]
[162513.517814] ? finish_wait+0x90/0x90
[162513.517829] start_transaction+0x37c/0x5f0 [btrfs]
[162513.517845] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
[162513.517857] btrfs_sync_fs+0x61/0x1c0 [btrfs]
[162513.517862] ? __ia32_sys_fdatasync+0x20/0x20
[162513.517865] iterate_supers+0x87/0xf0
[162513.517869] ksys_sync+0x60/0xb0
[162513.517872] __do_sys_sync+0xa/0x10
[162513.517875] do_syscall_64+0x33/0x80
[162513.517878] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.517881] RIP: 0033:0x7f5238f50bd7
[162513.517883] Code: Bad RIP value.
[162513.517885] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
[162513.517887] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
[162513.517889] RDX: 0000000000000000 RSI: 000000007660add2 RDI: 0000000000000053
[162513.517891] RBP: 0000000000000032 R08: 0000000000000067 R09: 00007f5239019be0
[162513.517893] R10: fffffffffffff24f R11: 0000000000000206 R12: 0000000000000053
[162513.517895] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
[162513.517908] INFO: task fsstress:1356197 blocked for more than 120 seconds.
[162513.518298] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.518672] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.519157] task:fsstress state:D stack: 0 pid:1356197 ppid:1356177 flags:0x00000000
[162513.519160] Call Trace:
[162513.519165] __schedule+0x5ce/0xd00
[162513.519168] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.519174] schedule+0x46/0xf0
[162513.519190] wait_current_trans+0xde/0x140 [btrfs]
[162513.519193] ? finish_wait+0x90/0x90
[162513.519206] start_transaction+0x4d7/0x5f0 [btrfs]
[162513.519222] btrfs_create+0x57/0x200 [btrfs]
[162513.519230] lookup_open+0x522/0x650
[162513.519246] path_openat+0x2b8/0xa50
[162513.519270] do_filp_open+0x91/0x100
[162513.519275] ? find_held_lock+0x32/0x90
[162513.519280] ? lock_acquired+0x33b/0x470
[162513.519285] ? do_raw_spin_unlock+0x4b/0xc0
[162513.519287] ? _raw_spin_unlock+0x29/0x40
[162513.519295] do_sys_openat2+0x20d/0x2d0
[162513.519300] do_sys_open+0x44/0x80
[162513.519304] do_syscall_64+0x33/0x80
[162513.519307] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.519309] RIP: 0033:0x7f5238f4a903
[162513.519310] Code: Bad RIP value.
[162513.519312] RSP: 002b:00007fff67b97758 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
[162513.519314] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f5238f4a903
[162513.519316] RDX: 0000000000000000 RSI: 00000000000001b6 RDI: 000055b1fbb0d470
[162513.519317] RBP: 00007fff67b978c0 R08: 0000000000000001 R09: 0000000000000002
[162513.519319] R10: 00007fff67b974f7 R11: 0000000000000246 R12: 0000000000000013
[162513.519320] R13: 00000000000001b6 R14: 00007fff67b97906 R15: 000055b1fad1c620
[162513.519332] INFO: task btrfs:1356211 blocked for more than 120 seconds.
[162513.519727] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.520115] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.520508] task:btrfs state:D stack: 0 pid:1356211 ppid:1356178 flags:0x00004002
[162513.520511] Call Trace:
[162513.520516] __schedule+0x5ce/0xd00
[162513.520519] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.520525] schedule+0x46/0xf0
[162513.520544] btrfs_scrub_pause+0x11f/0x180 [btrfs]
[162513.520548] ? finish_wait+0x90/0x90
[162513.520562] btrfs_commit_transaction+0x45a/0xc30 [btrfs]
[162513.520574] ? start_transaction+0xe0/0x5f0 [btrfs]
[162513.520596] btrfs_dev_replace_finishing+0x6d8/0x711 [btrfs]
[162513.520619] btrfs_dev_replace_by_ioctl.cold+0x1cc/0x1fd [btrfs]
[162513.520639] btrfs_ioctl+0x2a25/0x36f0 [btrfs]
[162513.520643] ? do_sigaction+0xf3/0x240
[162513.520645] ? find_held_lock+0x32/0x90
[162513.520648] ? do_sigaction+0xf3/0x240
[162513.520651] ? lock_acquired+0x33b/0x470
[162513.520655] ? _raw_spin_unlock_irq+0x24/0x50
[162513.520657] ? lockdep_hardirqs_on+0x7d/0x100
[162513.520660] ? _raw_spin_unlock_irq+0x35/0x50
[162513.520662] ? do_sigaction+0xf3/0x240
[162513.520671] ? __x64_sys_ioctl+0x83/0xb0
[162513.520672] __x64_sys_ioctl+0x83/0xb0
[162513.520677] do_syscall_64+0x33/0x80
[162513.520679] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.520681] RIP: 0033:0x7fc3cd307d87
[162513.520682] Code: Bad RIP value.
[162513.520684] RSP: 002b:00007ffe30a56bb8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
[162513.520686] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc3cd307d87
[162513.520687] RDX: 00007ffe30a57a30 RSI: 00000000ca289435 RDI: 0000000000000003
[162513.520689] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[162513.520690] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000003
[162513.520692] R13: 0000557323a212e0 R14: 00007ffe30a5a520 R15: 0000000000000001
[162513.520703]
Showing all locks held in the system:
[162513.520712] 1 lock held by khungtaskd/54:
[162513.520713] #0: ffffffffb40a91a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x197
[162513.520728] 1 lock held by in:imklog/596:
[162513.520729] #0: ffff8f3f0d781400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4d/0x60
[162513.520782] 1 lock held by btrfs-transacti/1356167:
[162513.520784] #0: ffff8f3d810cc848 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0x4a/0x170 [btrfs]
[162513.520798] 1 lock held by btrfs/1356190:
[162513.520800] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0x60
[162513.520805] 1 lock held by fsstress/1356184:
[162513.520806] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
[162513.520811] 3 locks held by fsstress/1356185:
[162513.520812] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
[162513.520815] #1: ffff8f3d80a650b8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: vfs_setxattr+0x50/0x120
[162513.520820] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
[162513.520833] 1 lock held by fsstress/1356196:
[162513.520834] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
[162513.520838] 3 locks held by fsstress/1356197:
[162513.520839] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
[162513.520843] #1: ffff8f3d506465e8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x2a7/0xa50
[162513.520846] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
[162513.520858] 2 locks held by btrfs/1356211:
[162513.520859] #0: ffff8f3d810cde30 (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.}-{3:3}, at: btrfs_dev_replace_finishing+0x52/0x711 [btrfs]
[162513.520877] #1: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
This was weird because the stack traces show that a transaction commit,
triggered by a device replace operation, is blocking trying to pause any
running scrubs but there are no stack traces of blocked tasks doing a
scrub.
After poking around with drgn, I noticed there was a scrub task that was
constantly running and blocking for shorts periods of time:
>>> t = find_task(prog, 1356190)
>>> prog.stack_trace(t)
#0 __schedule+0x5ce/0xcfc
#1 schedule+0x46/0xe4
#2 schedule_timeout+0x1df/0x475
#3 btrfs_reada_wait+0xda/0x132
#4 scrub_stripe+0x2a8/0x112f
#5 scrub_chunk+0xcd/0x134
#6 scrub_enumerate_chunks+0x29e/0x5ee
#7 btrfs_scrub_dev+0x2d5/0x91b
#8 btrfs_ioctl+0x7f5/0x36e7
#9 __x64_sys_ioctl+0x83/0xb0
#10 do_syscall_64+0x33/0x77
#11 entry_SYSCALL_64+0x7c/0x156
Which corresponds to:
int btrfs_reada_wait(void *handle)
{
struct reada_control *rc = handle;
struct btrfs_fs_info *fs_info = rc->fs_info;
while (atomic_read(&rc->elems)) {
if (!atomic_read(&fs_info->reada_works_cnt))
reada_start_machine(fs_info);
wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0,
(HZ + 9) / 10);
}
(...)
So the counter "rc->elems" was set to 1 and never decreased to 0, causing
the scrub task to loop forever in that function. Then I used the following
script for drgn to check the readahead requests:
$ cat dump_reada.py
import sys
import drgn
from drgn import NULL, Object, cast, container_of, execscript, \
reinterpret, sizeof
from drgn.helpers.linux import *
mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"
mnt = None
for mnt in for_each_mount(prog, dst = mnt_path):
pass
if mnt is None:
sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
sys.exit(1)
fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)
def dump_re(re):
nzones = re.nzones.value_()
print(f're at {hex(re.value_())}')
print(f'\t logical {re.logical.value_()}')
print(f'\t refcnt {re.refcnt.value_()}')
print(f'\t nzones {nzones}')
for i in range(nzones):
dev = re.zones[i].device
name = dev.name.str.string_()
print(f'\t\t dev id {dev.devid.value_()} name {name}')
print()
for _, e in radix_tree_for_each(fs_info.reada_tree):
re = cast('struct reada_extent *', e)
dump_re(re)
$ drgn dump_reada.py
re at 0xffff8f3da9d25ad8
logical 38928384
refcnt 1
nzones 1
dev id 0 name b'/dev/sdd'
$
So there was one readahead extent with a single zone corresponding to the
source device of that last device replace operation logged in dmesg/syslog.
Also the ID of that zone's device was 0 which is a special value set in
the source device of a device replace operation when the operation finishes
(constant BTRFS_DEV_REPLACE_DEVID set at btrfs_dev_replace_finishing()),
confirming again that device /dev/sdd was the source of a device replace
operation.
Normally there should be as many zones in the readahead extent as there are
devices, and I wasn't expecting the extent to be in a block group with a
'single' profile, so I went and confirmed with the following drgn script
that there weren't any single profile block groups:
$ cat dump_block_groups.py
import sys
import drgn
from drgn import NULL, Object, cast, container_of, execscript, \
reinterpret, sizeof
from drgn.helpers.linux import *
mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"
mnt = None
for mnt in for_each_mount(prog, dst = mnt_path):
pass
if mnt is None:
sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
sys.exit(1)
fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)
BTRFS_BLOCK_GROUP_DATA = (1 << 0)
BTRFS_BLOCK_GROUP_SYSTEM = (1 << 1)
BTRFS_BLOCK_GROUP_METADATA = (1 << 2)
BTRFS_BLOCK_GROUP_RAID0 = (1 << 3)
BTRFS_BLOCK_GROUP_RAID1 = (1 << 4)
BTRFS_BLOCK_GROUP_DUP = (1 << 5)
BTRFS_BLOCK_GROUP_RAID10 = (1 << 6)
BTRFS_BLOCK_GROUP_RAID5 = (1 << 7)
BTRFS_BLOCK_GROUP_RAID6 = (1 << 8)
BTRFS_BLOCK_GROUP_RAID1C3 = (1 << 9)
BTRFS_BLOCK_GROUP_RAID1C4 = (1 << 10)
def bg_flags_string(bg):
flags = bg.flags.value_()
ret = ''
if flags & BTRFS_BLOCK_GROUP_DATA:
ret = 'data'
if flags & BTRFS_BLOCK_GROUP_METADATA:
if len(ret) > 0:
ret += '|'
ret += 'meta'
if flags & BTRFS_BLOCK_GROUP_SYSTEM:
if len(ret) > 0:
ret += '|'
ret += 'system'
if flags & BTRFS_BLOCK_GROUP_RAID0:
ret += ' raid0'
elif flags & BTRFS_BLOCK_GROUP_RAID1:
ret += ' raid1'
elif flags & BTRFS_BLOCK_GROUP_DUP:
ret += ' dup'
elif flags & BTRFS_BLOCK_GROUP_RAID10:
ret += ' raid10'
elif flags & BTRFS_BLOCK_GROUP_RAID5:
ret += ' raid5'
elif flags & BTRFS_BLOCK_GROUP_RAID6:
ret += ' raid6'
elif flags & BTRFS_BLOCK_GROUP_RAID1C3:
ret += ' raid1c3'
elif flags & BTRFS_BLOCK_GROUP_RAID1C4:
ret += ' raid1c4'
else:
ret += ' single'
return ret
def dump_bg(bg):
print()
print(f'block group at {hex(bg.value_())}')
print(f'\t start {bg.start.value_()} length {bg.length.value_()}')
print(f'\t flags {bg.flags.value_()} - {bg_flags_string(bg)}')
bg_root = fs_info.block_group_cache_tree.address_of_()
for bg in rbtree_inorder_for_each_entry('struct btrfs_block_group', bg_root, 'cache_node'):
dump_bg(bg)
$ drgn dump_block_groups.py
block group at 0xffff8f3d673b0400
start 22020096 length 16777216
flags 258 - system raid6
block group at 0xffff8f3d53ddb400
start 38797312 length 536870912
flags 260 - meta raid6
block group at 0xffff8f3d5f4d9c00
start 575668224 length 2147483648
flags 257 - data raid6
block group at 0xffff8f3d08189000
start 2723151872 length 67108864
flags 258 - system raid6
block group at 0xffff8f3db70ff000
start 2790260736 length 1073741824
flags 260 - meta raid6
block group at 0xffff8f3d5f4dd800
start 3864002560 length 67108864
flags 258 - system raid6
block group at 0xffff8f3d67037000
start 3931111424 length 2147483648
flags 257 - data raid6
$
So there were only 2 reasons left for having a readahead extent with a
single zone: reada_find_zone(), called when creating a readahead extent,
returned NULL either because we failed to find the corresponding block
group or because a memory allocation failed. With some additional and
custom tracing I figured out that on every further ocurrence of the
problem the block group had just been deleted when we were looping to
create the zones for the readahead extent (at reada_find_extent()), so we
ended up with only one zone in the readahead extent, corresponding to a
device that ends up getting replaced.
So after figuring that out it became obvious why the hang happens:
1) Task A starts a scrub on any device of the filesystem, except for
device /dev/sdd;
2) Task B starts a device replace with /dev/sdd as the source device;
3) Task A calls btrfs_reada_add() from scrub_stripe() and it is currently
starting to scrub a stripe from block group X. This call to
btrfs_reada_add() is the one for the extent tree. When btrfs_reada_add()
calls reada_add_block(), it passes the logical address of the extent
tree's root node as its 'logical' argument - a value of 38928384;
4) Task A then enters reada_find_extent(), called from reada_add_block().
It finds there isn't any existing readahead extent for the logical
address 38928384, so it proceeds to the path of creating a new one.
It calls btrfs_map_block() to find out which stripes exist for the block
group X. On the first iteration of the for loop that iterates over the
stripes, it finds the stripe for device /dev/sdd, so it creates one
zone for that device and adds it to the readahead extent. Before getting
into the second iteration of the loop, the cleanup kthread deletes block
group X because it was empty. So in the iterations for the remaining
stripes it does not add more zones to the readahead extent, because the
calls to reada_find_zone() returned NULL because they couldn't find
block group X anymore.
As a result the new readahead extent has a single zone, corresponding to
the device /dev/sdd;
4) Before task A returns to btrfs_reada_add() and queues the readahead job
for the readahead work queue, task B finishes the device replace and at
btrfs_dev_replace_finishing() swaps the device /dev/sdd with the new
device /dev/sdg;
5) Task A returns to reada_add_block(), which increments the counter
"->elems" of the reada_control structure allocated at btrfs_reada_add().
Then it returns back to btrfs_reada_add() and calls
reada_start_machine(). This queues a job in the readahead work queue to
run the function reada_start_machine_worker(), which calls
__reada_start_machine().
At __reada_start_machine() we take the device list mutex and for each
device found in the current device list, we call
reada_start_machine_dev() to start the readahead work. However at this
point the device /dev/sdd was already freed and is not in the device
list anymore.
This means the corresponding readahead for the extent at 38928384 is
never started, and therefore the "->elems" counter of the reada_control
structure allocated at btrfs_reada_add() never goes down to 0, causing
the call to btrfs_reada_wait(), done by the scrub task, to wait forever.
Note that the readahead request can be made either after the device replace
started or before it started, however in pratice it is very unlikely that a
device replace is able to start after a readahead request is made and is
able to complete before the readahead request completes - maybe only on a
very small and nearly empty filesystem.
This hang however is not the only problem we can have with readahead and
device removals. When the readahead extent has other zones other than the
one corresponding to the device that is being removed (either by a device
replace or a device remove operation), we risk having a use-after-free on
the device when dropping the last reference of the readahead extent.
For example if we create a readahead extent with two zones, one for the
device /dev/sdd and one for the device /dev/sde:
1) Before the readahead worker starts, the device /dev/sdd is removed,
and the corresponding btrfs_device structure is freed. However the
readahead extent still has the zone pointing to the device structure;
2) When the readahead worker starts, it only finds device /dev/sde in the
current device list of the filesystem;
3) It starts the readahead work, at reada_start_machine_dev(), using the
device /dev/sde;
4) Then when it finishes reading the extent from device /dev/sde, it calls
__readahead_hook() which ends up dropping the last reference on the
readahead extent through the last call to reada_extent_put();
5) At reada_extent_put() it iterates over each zone of the readahead extent
and attempts to delete an element from the device's 'reada_extents'
radix tree, resulting in a use-after-free, as the device pointer of the
zone for /dev/sdd is now stale. We can also access the device after
dropping the last reference of a zone, through reada_zone_release(),
also called by reada_extent_put().
And a device remove suffers the same problem, however since it shrinks the
device size down to zero before removing the device, it is very unlikely to
still have readahead requests not completed by the time we free the device,
the only possibility is if the device has a very little space allocated.
While the hang problem is exclusive to scrub, since it is currently the
only user of btrfs_reada_add() and btrfs_reada_wait(), the use-after-free
problem affects any path that triggers readhead, which includes
btree_readahead_hook() and __readahead_hook() (a readahead worker can
trigger readahed for the children of a node) for example - any path that
ends up calling reada_add_block() can trigger the use-after-free after a
device is removed.
So fix this by waiting for any readahead requests for a device to complete
before removing a device, ensuring that while waiting for existing ones no
new ones can be made.
This problem has been around for a very long time - the readahead code was
added in 2011, device remove exists since 2008 and device replace was
introduced in 2013, hard to pick a specific commit for a git Fixes tag.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 83bc1560e0 upstream.
If we fail to find suitable zones for a new readahead extent, we end up
leaving a stale pointer in the global readahead extents radix tree
(fs_info->reada_tree), which can trigger the following trace later on:
[13367.696354] BUG: kernel NULL pointer dereference, address: 00000000000000b0
[13367.696802] #PF: supervisor read access in kernel mode
[13367.697249] #PF: error_code(0x0000) - not-present page
[13367.697721] PGD 0 P4D 0
[13367.698171] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
[13367.698632] CPU: 6 PID: 851214 Comm: btrfs Tainted: G W 5.9.0-rc6-btrfs-next-69 #1
[13367.699100] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[13367.700069] RIP: 0010:__lock_acquire+0x20a/0x3970
[13367.700562] Code: ff 1f 0f b7 c0 48 0f (...)
[13367.701609] RSP: 0018:ffffb14448f57790 EFLAGS: 00010046
[13367.702140] RAX: 0000000000000000 RBX: 29b935140c15e8cf RCX: 0000000000000000
[13367.702698] RDX: 0000000000000002 RSI: ffffffffb3d66bd0 RDI: 0000000000000046
[13367.703240] RBP: ffff8a52ba8ac040 R08: 00000c2866ad9288 R09: 0000000000000001
[13367.703783] R10: 0000000000000001 R11: 00000000b66d9b53 R12: ffff8a52ba8ac9b0
[13367.704330] R13: 0000000000000000 R14: ffff8a532b6333e8 R15: 0000000000000000
[13367.704880] FS: 00007fe1df6b5700(0000) GS:ffff8a5376600000(0000) knlGS:0000000000000000
[13367.705438] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[13367.705995] CR2: 00000000000000b0 CR3: 000000022cca8004 CR4: 00000000003706e0
[13367.706565] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[13367.707127] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[13367.707686] Call Trace:
[13367.708246] ? ___slab_alloc+0x395/0x740
[13367.708820] ? reada_add_block+0xae/0xee0 [btrfs]
[13367.709383] lock_acquire+0xb1/0x480
[13367.709955] ? reada_add_block+0xe0/0xee0 [btrfs]
[13367.710537] ? reada_add_block+0xae/0xee0 [btrfs]
[13367.711097] ? rcu_read_lock_sched_held+0x5d/0x90
[13367.711659] ? kmem_cache_alloc_trace+0x8d2/0x990
[13367.712221] ? lock_acquired+0x33b/0x470
[13367.712784] _raw_spin_lock+0x34/0x80
[13367.713356] ? reada_add_block+0xe0/0xee0 [btrfs]
[13367.713966] reada_add_block+0xe0/0xee0 [btrfs]
[13367.714529] ? btrfs_root_node+0x15/0x1f0 [btrfs]
[13367.715077] btrfs_reada_add+0x117/0x170 [btrfs]
[13367.715620] scrub_stripe+0x21e/0x10d0 [btrfs]
[13367.716141] ? kvm_sched_clock_read+0x5/0x10
[13367.716657] ? __lock_acquire+0x41e/0x3970
[13367.717184] ? scrub_chunk+0x60/0x140 [btrfs]
[13367.717697] ? find_held_lock+0x32/0x90
[13367.718254] ? scrub_chunk+0x60/0x140 [btrfs]
[13367.718773] ? lock_acquired+0x33b/0x470
[13367.719278] ? scrub_chunk+0xcd/0x140 [btrfs]
[13367.719786] scrub_chunk+0xcd/0x140 [btrfs]
[13367.720291] scrub_enumerate_chunks+0x270/0x5c0 [btrfs]
[13367.720787] ? finish_wait+0x90/0x90
[13367.721281] btrfs_scrub_dev+0x1ee/0x620 [btrfs]
[13367.721762] ? rcu_read_lock_any_held+0x8e/0xb0
[13367.722235] ? preempt_count_add+0x49/0xa0
[13367.722710] ? __sb_start_write+0x19b/0x290
[13367.723192] btrfs_ioctl+0x7f5/0x36f0 [btrfs]
[13367.723660] ? __fget_files+0x101/0x1d0
[13367.724118] ? find_held_lock+0x32/0x90
[13367.724559] ? __fget_files+0x101/0x1d0
[13367.724982] ? __x64_sys_ioctl+0x83/0xb0
[13367.725399] __x64_sys_ioctl+0x83/0xb0
[13367.725802] do_syscall_64+0x33/0x80
[13367.726188] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[13367.726574] RIP: 0033:0x7fe1df7add87
[13367.726948] Code: 00 00 00 48 8b 05 09 91 (...)
[13367.727763] RSP: 002b:00007fe1df6b4d48 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[13367.728179] RAX: ffffffffffffffda RBX: 000055ce1fb596a0 RCX: 00007fe1df7add87
[13367.728604] RDX: 000055ce1fb596a0 RSI: 00000000c400941b RDI: 0000000000000003
[13367.729021] RBP: 0000000000000000 R08: 00007fe1df6b5700 R09: 0000000000000000
[13367.729431] R10: 00007fe1df6b5700 R11: 0000000000000246 R12: 00007ffd922b07de
[13367.729842] R13: 00007ffd922b07df R14: 00007fe1df6b4e40 R15: 0000000000802000
[13367.730275] Modules linked in: btrfs blake2b_generic xor (...)
[13367.732638] CR2: 00000000000000b0
[13367.733166] ---[ end trace d298b6805556acd9 ]---
What happens is the following:
1) At reada_find_extent() we don't find any existing readahead extent for
the metadata extent starting at logical address X;
2) So we proceed to create a new one. We then call btrfs_map_block() to get
information about which stripes contain extent X;
3) After that we iterate over the stripes and create only one zone for the
readahead extent - only one because reada_find_zone() returned NULL for
all iterations except for one, either because a memory allocation failed
or it couldn't find the block group of the extent (it may have just been
deleted);
4) We then add the new readahead extent to the readahead extents radix
tree at fs_info->reada_tree;
5) Then we iterate over each zone of the new readahead extent, and find
that the device used for that zone no longer exists, because it was
removed or it was the source device of a device replace operation.
Since this left 'have_zone' set to 0, after finishing the loop we jump
to the 'error' label, call kfree() on the new readahead extent and
return without removing it from the radix tree at fs_info->reada_tree;
6) Any future call to reada_find_extent() for the logical address X will
find the stale pointer in the readahead extents radix tree, increment
its reference counter, which can trigger the use-after-free right
away or return it to the caller reada_add_block() that results in the
use-after-free of the example trace above.
So fix this by making sure we delete the readahead extent from the radix
tree if we fail to setup zones for it (when 'have_zone = 0').
Fixes: 3194502118 ("btrfs: reada: bypass adding extent when all zone failed")
CC: stable@vger.kernel.org # 4.9+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 85d07fbe09 upstream.
If there's no parity and num_stripes < ncopies, a crafted image can
trigger a division by zero in calc_stripe_length().
The image was generated through fuzzing.
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=209587
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 572c83acdc upstream.
In fstest btrfs/064 a transaction abort in __btrfs_cow_block could lead
to a system lockup. It gets stuck trying to write back inodes, and the
write back thread was trying to lock an extent buffer:
$ cat /proc/2143497/stack
[<0>] __btrfs_tree_lock+0x108/0x250
[<0>] lock_extent_buffer_for_io+0x35e/0x3a0
[<0>] btree_write_cache_pages+0x15a/0x3b0
[<0>] do_writepages+0x28/0xb0
[<0>] __writeback_single_inode+0x54/0x5c0
[<0>] writeback_sb_inodes+0x1e8/0x510
[<0>] wb_writeback+0xcc/0x440
[<0>] wb_workfn+0xd7/0x650
[<0>] process_one_work+0x236/0x560
[<0>] worker_thread+0x55/0x3c0
[<0>] kthread+0x13a/0x150
[<0>] ret_from_fork+0x1f/0x30
This is because we got an error while COWing a block, specifically here
if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state)) {
ret = btrfs_reloc_cow_block(trans, root, buf, cow);
if (ret) {
btrfs_abort_transaction(trans, ret);
return ret;
}
}
[16402.241552] BTRFS: Transaction aborted (error -2)
[16402.242362] WARNING: CPU: 1 PID: 2563188 at fs/btrfs/ctree.c:1074 __btrfs_cow_block+0x376/0x540
[16402.249469] CPU: 1 PID: 2563188 Comm: fsstress Not tainted 5.9.0-rc6+ #8
[16402.249936] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
[16402.250525] RIP: 0010:__btrfs_cow_block+0x376/0x540
[16402.252417] RSP: 0018:ffff9cca40e578b0 EFLAGS: 00010282
[16402.252787] RAX: 0000000000000025 RBX: 0000000000000002 RCX: ffff9132bbd19388
[16402.253278] RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffff9132bbd19380
[16402.254063] RBP: ffff9132b41a49c0 R08: 0000000000000000 R09: 0000000000000000
[16402.254887] R10: 0000000000000000 R11: ffff91324758b080 R12: ffff91326ef17ce0
[16402.255694] R13: ffff91325fc0f000 R14: ffff91326ef176b0 R15: ffff9132815e2000
[16402.256321] FS: 00007f542c6d7b80(0000) GS:ffff9132bbd00000(0000) knlGS:0000000000000000
[16402.256973] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[16402.257374] CR2: 00007f127b83f250 CR3: 0000000133480002 CR4: 0000000000370ee0
[16402.257867] Call Trace:
[16402.258072] btrfs_cow_block+0x109/0x230
[16402.258356] btrfs_search_slot+0x530/0x9d0
[16402.258655] btrfs_lookup_file_extent+0x37/0x40
[16402.259155] __btrfs_drop_extents+0x13c/0xd60
[16402.259628] ? btrfs_block_rsv_migrate+0x4f/0xb0
[16402.259949] btrfs_replace_file_extents+0x190/0x820
[16402.260873] btrfs_clone+0x9ae/0xc00
[16402.261139] btrfs_extent_same_range+0x66/0x90
[16402.261771] btrfs_remap_file_range+0x353/0x3b1
[16402.262333] vfs_dedupe_file_range_one.part.0+0xd5/0x140
[16402.262821] vfs_dedupe_file_range+0x189/0x220
[16402.263150] do_vfs_ioctl+0x552/0x700
[16402.263662] __x64_sys_ioctl+0x62/0xb0
[16402.264023] do_syscall_64+0x33/0x40
[16402.264364] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[16402.264862] RIP: 0033:0x7f542c7d15cb
[16402.266901] RSP: 002b:00007ffd35944ea8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[16402.267627] RAX: ffffffffffffffda RBX: 00000000009d1968 RCX: 00007f542c7d15cb
[16402.268298] RDX: 00000000009d2490 RSI: 00000000c0189436 RDI: 0000000000000003
[16402.268958] RBP: 00000000009d2520 R08: 0000000000000036 R09: 00000000009d2e64
[16402.269726] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
[16402.270659] R13: 000000000001f000 R14: 00000000009d1970 R15: 00000000009d2e80
[16402.271498] irq event stamp: 0
[16402.271846] hardirqs last enabled at (0): [<0000000000000000>] 0x0
[16402.272497] hardirqs last disabled at (0): [<ffffffff910dbf59>] copy_process+0x6b9/0x1ba0
[16402.273343] softirqs last enabled at (0): [<ffffffff910dbf59>] copy_process+0x6b9/0x1ba0
[16402.273905] softirqs last disabled at (0): [<0000000000000000>] 0x0
[16402.274338] ---[ end trace 737874a5a41a8236 ]---
[16402.274669] BTRFS: error (device dm-9) in __btrfs_cow_block:1074: errno=-2 No such entry
[16402.276179] BTRFS info (device dm-9): forced readonly
[16402.277046] BTRFS: error (device dm-9) in btrfs_replace_file_extents:2723: errno=-2 No such entry
[16402.278744] BTRFS: error (device dm-9) in __btrfs_cow_block:1074: errno=-2 No such entry
[16402.279968] BTRFS: error (device dm-9) in __btrfs_cow_block:1074: errno=-2 No such entry
[16402.280582] BTRFS info (device dm-9): balance: ended with status: -30
The problem here is that as soon as we allocate the new block it is
locked and marked dirty in the btree inode. This means that we could
attempt to writeback this block and need to lock the extent buffer.
However we're not unlocking it here and thus we deadlock.
Fix this by unlocking the cow block if we have any errors inside of
__btrfs_cow_block, and also free it so we do not leak it.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1465af12e2 upstream.
Commit 259ee7754b ("btrfs: tree-checker: Add ROOT_ITEM check")
introduced btrfs root item size check, however btrfs root item has two
versions, the legacy one which just ends before generation_v2 member, is
smaller than current btrfs root item size.
This caused btrfs kernel to reject valid but old tree root leaves.
Fix this problem by also allowing legacy root item, since kernel can
already handle them pretty well and upgrade to newer root item format
when needed.
Reported-by: Martin Steigerwald <martin@lichtvoll.de>
Fixes: 259ee7754b ("btrfs: tree-checker: Add ROOT_ITEM check")
CC: stable@vger.kernel.org # 5.4+
Tested-By: Martin Steigerwald <martin@lichtvoll.de>
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 8eb2fd0015 upstream.
btrfs_ioctl_send() used open-coded kvzalloc implementation earlier.
The code was accidentally replaced with kzalloc() call [1]. Restore
the original code by using kvzalloc() to allocate sctx->clone_roots.
[1] https://patchwork.kernel.org/patch/9757891/#20529627
Fixes: 818e010bf9 ("btrfs: replace opencoded kvzalloc with the helper")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Denis Efremov <efremov@linux.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 9c2b4e0347 upstream.
During an incremental send, when an inode has multiple new references we
might end up emitting rename operations for orphanizations that have a
source path that is no longer valid due to a previous orphanization of
some directory inode. This causes the receiver to fail since it tries
to rename a path that does not exists.
Example reproducer:
$ cat reproducer.sh
#!/bin/bash
mkfs.btrfs -f /dev/sdi >/dev/null
mount /dev/sdi /mnt/sdi
touch /mnt/sdi/f1
touch /mnt/sdi/f2
mkdir /mnt/sdi/d1
mkdir /mnt/sdi/d1/d2
# Filesystem looks like:
#
# . (ino 256)
# |----- f1 (ino 257)
# |----- f2 (ino 258)
# |----- d1/ (ino 259)
# |----- d2/ (ino 260)
btrfs subvolume snapshot -r /mnt/sdi /mnt/sdi/snap1
btrfs send -f /tmp/snap1.send /mnt/sdi/snap1
# Now do a series of changes such that:
#
# *) inode 258 has one new hardlink and the previous name changed
#
# *) both names conflict with the old names of two other inodes:
#
# 1) the new name "d1" conflicts with the old name of inode 259,
# under directory inode 256 (root)
#
# 2) the new name "d2" conflicts with the old name of inode 260
# under directory inode 259
#
# *) inodes 259 and 260 now have the old names of inode 258
#
# *) inode 257 is now located under inode 260 - an inode with a number
# smaller than the inode (258) for which we created a second hard
# link and swapped its names with inodes 259 and 260
#
ln /mnt/sdi/f2 /mnt/sdi/d1/f2_link
mv /mnt/sdi/f1 /mnt/sdi/d1/d2/f1
# Swap d1 and f2.
mv /mnt/sdi/d1 /mnt/sdi/tmp
mv /mnt/sdi/f2 /mnt/sdi/d1
mv /mnt/sdi/tmp /mnt/sdi/f2
# Swap d2 and f2_link
mv /mnt/sdi/f2/d2 /mnt/sdi/tmp
mv /mnt/sdi/f2/f2_link /mnt/sdi/f2/d2
mv /mnt/sdi/tmp /mnt/sdi/f2/f2_link
# Filesystem now looks like:
#
# . (ino 256)
# |----- d1 (ino 258)
# |----- f2/ (ino 259)
# |----- f2_link/ (ino 260)
# | |----- f1 (ino 257)
# |
# |----- d2 (ino 258)
btrfs subvolume snapshot -r /mnt/sdi /mnt/sdi/snap2
btrfs send -f /tmp/snap2.send -p /mnt/sdi/snap1 /mnt/sdi/snap2
mkfs.btrfs -f /dev/sdj >/dev/null
mount /dev/sdj /mnt/sdj
btrfs receive -f /tmp/snap1.send /mnt/sdj
btrfs receive -f /tmp/snap2.send /mnt/sdj
umount /mnt/sdi
umount /mnt/sdj
When executed the receive of the incremental stream fails:
$ ./reproducer.sh
Create a readonly snapshot of '/mnt/sdi' in '/mnt/sdi/snap1'
At subvol /mnt/sdi/snap1
Create a readonly snapshot of '/mnt/sdi' in '/mnt/sdi/snap2'
At subvol /mnt/sdi/snap2
At subvol snap1
At snapshot snap2
ERROR: rename d1/d2 -> o260-6-0 failed: No such file or directory
This happens because:
1) When processing inode 257 we end up computing the name for inode 259
because it is an ancestor in the send snapshot, and at that point it
still has its old name, "d1", from the parent snapshot because inode
259 was not yet processed. We then cache that name, which is valid
until we start processing inode 259 (or set the progress to 260 after
processing its references);
2) Later we start processing inode 258 and collecting all its new
references into the list sctx->new_refs. The first reference in the
list happens to be the reference for name "d1" while the reference for
name "d2" is next (the last element of the list).
We compute the full path "d1/d2" for this second reference and store
it in the reference (its ->full_path member). The path used for the
new parent directory was "d1" and not "f2" because inode 259, the
new parent, was not yet processed;
3) When we start processing the new references at process_recorded_refs()
we start with the first reference in the list, for the new name "d1".
Because there is a conflicting inode that was not yet processed, which
is directory inode 259, we orphanize it, renaming it from "d1" to
"o259-6-0";
4) Then we start processing the new reference for name "d2", and we
realize it conflicts with the reference of inode 260 in the parent
snapshot. So we issue an orphanization operation for inode 260 by
emitting a rename operation with a destination path of "o260-6-0"
and a source path of "d1/d2" - this source path is the value we
stored in the reference earlier at step 2), corresponding to the
->full_path member of the reference, however that path is no longer
valid due to the orphanization of the directory inode 259 in step 3).
This makes the receiver fail since the path does not exists, it should
have been "o259-6-0/d2".
Fix this by recomputing the full path of a reference before emitting an
orphanization if we previously orphanized any directory, since that
directory could be a parent in the new path. This is a rare scenario so
keeping it simple and not checking if that previously orphanized directory
is in fact an ancestor of the inode we are trying to orphanize.
A test case for fstests follows soon.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.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 98272bb77b upstream.
When doing an incremental send it is possible that when processing the new
references for an inode we end up issuing rename or link operations that
have an invalid path, which contains the orphanized name of a directory
before we actually orphanized it, causing the receiver to fail.
The following reproducer triggers such scenario:
$ cat reproducer.sh
#!/bin/bash
mkfs.btrfs -f /dev/sdi >/dev/null
mount /dev/sdi /mnt/sdi
touch /mnt/sdi/a
touch /mnt/sdi/b
mkdir /mnt/sdi/testdir
# We want "a" to have a lower inode number then "testdir" (257 vs 259).
mv /mnt/sdi/a /mnt/sdi/testdir/a
# Filesystem looks like:
#
# . (ino 256)
# |----- testdir/ (ino 259)
# | |----- a (ino 257)
# |
# |----- b (ino 258)
btrfs subvolume snapshot -r /mnt/sdi /mnt/sdi/snap1
btrfs send -f /tmp/snap1.send /mnt/sdi/snap1
# Now rename 259 to "testdir_2", then change the name of 257 to
# "testdir" and make it a direct descendant of the root inode (256).
# Also create a new link for inode 257 with the old name of inode 258.
# By swapping the names and location of several inodes and create a
# nasty dependency chain of rename and link operations.
mv /mnt/sdi/testdir/a /mnt/sdi/a2
touch /mnt/sdi/testdir/a
mv /mnt/sdi/b /mnt/sdi/b2
ln /mnt/sdi/a2 /mnt/sdi/b
mv /mnt/sdi/testdir /mnt/sdi/testdir_2
mv /mnt/sdi/a2 /mnt/sdi/testdir
# Filesystem now looks like:
#
# . (ino 256)
# |----- testdir_2/ (ino 259)
# | |----- a (ino 260)
# |
# |----- testdir (ino 257)
# |----- b (ino 257)
# |----- b2 (ino 258)
btrfs subvolume snapshot -r /mnt/sdi /mnt/sdi/snap2
btrfs send -f /tmp/snap2.send -p /mnt/sdi/snap1 /mnt/sdi/snap2
mkfs.btrfs -f /dev/sdj >/dev/null
mount /dev/sdj /mnt/sdj
btrfs receive -f /tmp/snap1.send /mnt/sdj
btrfs receive -f /tmp/snap2.send /mnt/sdj
umount /mnt/sdi
umount /mnt/sdj
When running the reproducer, the receive of the incremental send stream
fails:
$ ./reproducer.sh
Create a readonly snapshot of '/mnt/sdi' in '/mnt/sdi/snap1'
At subvol /mnt/sdi/snap1
Create a readonly snapshot of '/mnt/sdi' in '/mnt/sdi/snap2'
At subvol /mnt/sdi/snap2
At subvol snap1
At snapshot snap2
ERROR: link b -> o259-6-0/a failed: No such file or directory
The problem happens because of the following:
1) Before we start iterating the list of new references for inode 257,
we generate its current path and store it at @valid_path, done at
the very beginning of process_recorded_refs(). The generated path
is "o259-6-0/a", containing the orphanized name for inode 259;
2) Then we iterate over the list of new references, which has the
references "b" and "testdir" in that specific order;
3) We process reference "b" first, because it is in the list before
reference "testdir". We then issue a link operation to create
the new reference "b" using a target path corresponding to the
content at @valid_path, which corresponds to "o259-6-0/a".
However we haven't yet orphanized inode 259, its name is still
"testdir", and not "o259-6-0". The orphanization of 259 did not
happen yet because we will process the reference named "testdir"
for inode 257 only in the next iteration of the loop that goes
over the list of new references.
Fix the issue by having a preliminar iteration over all the new references
at process_recorded_refs(). This iteration is responsible only for doing
the orphanization of other inodes that have and old reference that
conflicts with one of the new references of the inode we are currently
processing. The emission of rename and link operations happen now in the
next iteration of the new references.
A test case for fstests will follow soon.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.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 bb56f02f26 upstream.
Logging directories with many entries can take a significant amount of
time, and in some cases monopolize a cpu/core for a long time if the
logging task doesn't happen to block often enough.
Johannes and Lu Fengqi reported test case generic/041 triggering a soft
lockup when the kernel has CONFIG_SOFTLOCKUP_DETECTOR=y. For this test
case we log an inode with 3002 hard links, and because the test removed
one hard link before fsyncing the file, the inode logging causes the
parent directory do be logged as well, which has 6004 directory items to
log (3002 BTRFS_DIR_ITEM_KEY items plus 3002 BTRFS_DIR_INDEX_KEY items),
so it can take a significant amount of time and trigger the soft lockup.
So just make tree-log.c:log_dir_items() reschedule when necessary,
releasing the current search path before doing so and then resume from
where it was before the reschedule.
The stack trace produced when the soft lockup happens is the following:
[10480.277653] watchdog: BUG: soft lockup - CPU#2 stuck for 22s! [xfs_io:28172]
[10480.279418] Modules linked in: dm_thin_pool dm_persistent_data (...)
[10480.284915] irq event stamp: 29646366
[10480.285987] hardirqs last enabled at (29646365): [<ffffffff85249b66>] __slab_alloc.constprop.0+0x56/0x60
[10480.288482] hardirqs last disabled at (29646366): [<ffffffff8579b00d>] irqentry_enter+0x1d/0x50
[10480.290856] softirqs last enabled at (4612): [<ffffffff85a00323>] __do_softirq+0x323/0x56c
[10480.293615] softirqs last disabled at (4483): [<ffffffff85800dbf>] asm_call_on_stack+0xf/0x20
[10480.296428] CPU: 2 PID: 28172 Comm: xfs_io Not tainted 5.9.0-rc4-default+ #1248
[10480.298948] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
[10480.302455] RIP: 0010:__slab_alloc.constprop.0+0x19/0x60
[10480.304151] Code: 86 e8 31 75 21 00 66 66 2e 0f 1f 84 00 00 00 (...)
[10480.309558] RSP: 0018:ffffadbe09397a58 EFLAGS: 00000282
[10480.311179] RAX: ffff8a495ab92840 RBX: 0000000000000282 RCX: 0000000000000006
[10480.313242] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff85249b66
[10480.315260] RBP: ffff8a497d04b740 R08: 0000000000000001 R09: 0000000000000001
[10480.317229] R10: ffff8a497d044800 R11: ffff8a495ab93c40 R12: 0000000000000000
[10480.319169] R13: 0000000000000000 R14: 0000000000000c40 R15: ffffffffc01daf70
[10480.321104] FS: 00007fa1dc5c0e40(0000) GS:ffff8a497da00000(0000) knlGS:0000000000000000
[10480.323559] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[10480.325235] CR2: 00007fa1dc5befb8 CR3: 0000000004f8a006 CR4: 0000000000170ea0
[10480.327259] Call Trace:
[10480.328286] ? overwrite_item+0x1f0/0x5a0 [btrfs]
[10480.329784] __kmalloc+0x831/0xa20
[10480.331009] ? btrfs_get_32+0xb0/0x1d0 [btrfs]
[10480.332464] overwrite_item+0x1f0/0x5a0 [btrfs]
[10480.333948] log_dir_items+0x2ee/0x570 [btrfs]
[10480.335413] log_directory_changes+0x82/0xd0 [btrfs]
[10480.336926] btrfs_log_inode+0xc9b/0xda0 [btrfs]
[10480.338374] ? init_once+0x20/0x20 [btrfs]
[10480.339711] btrfs_log_inode_parent+0x8d3/0xd10 [btrfs]
[10480.341257] ? dget_parent+0x97/0x2e0
[10480.342480] btrfs_log_dentry_safe+0x3a/0x50 [btrfs]
[10480.343977] btrfs_sync_file+0x24b/0x5e0 [btrfs]
[10480.345381] do_fsync+0x38/0x70
[10480.346483] __x64_sys_fsync+0x10/0x20
[10480.347703] do_syscall_64+0x2d/0x70
[10480.348891] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[10480.350444] RIP: 0033:0x7fa1dc80970b
[10480.351642] Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 (...)
[10480.356952] RSP: 002b:00007fffb3d081d0 EFLAGS: 00000293 ORIG_RAX: 000000000000004a
[10480.359458] RAX: ffffffffffffffda RBX: 0000562d93d45e40 RCX: 00007fa1dc80970b
[10480.361426] RDX: 0000562d93d44ab0 RSI: 0000562d93d45e60 RDI: 0000000000000003
[10480.363367] RBP: 0000000000000001 R08: 0000000000000000 R09: 00007fa1dc7b2a40
[10480.365317] R10: 0000562d93d0e366 R11: 0000000000000293 R12: 0000000000000001
[10480.367299] R13: 0000562d93d45290 R14: 0000562d93d45e40 R15: 0000562d93d45e60
Link: https://lore.kernel.org/linux-btrfs/20180713090216.GC575@fnst.localdomain/
Reported-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
CC: stable@vger.kernel.org # 4.4+
Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 79dae17d8d upstream.
Systems booting without the initramfs seems to scan an unusual kind
of device path (/dev/root). And at a later time, the device is updated
to the correct path. We generally print the process name and PID of the
process scanning the device but we don't capture the same information if
the device path is rescanned with a different pathname.
The current message is too long, so drop the unnecessary UUID and add
process name and PID.
While at this also update the duplicate device warning to include the
process name and PID so the messages are consistent
CC: stable@vger.kernel.org # 4.19+
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=89721
Signed-off-by: Anand Jain <anand.jain@oracle.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 b4c5d8fdff upstream.
For delayed inode facility, qgroup metadata is reserved for it, and
later freed.
However we're freeing more bytes than we reserved.
In btrfs_delayed_inode_reserve_metadata():
num_bytes = btrfs_calc_metadata_size(fs_info, 1);
...
ret = btrfs_qgroup_reserve_meta_prealloc(root,
fs_info->nodesize, true);
...
if (!ret) {
node->bytes_reserved = num_bytes;
But in btrfs_delayed_inode_release_metadata():
if (qgroup_free)
btrfs_qgroup_free_meta_prealloc(node->root,
node->bytes_reserved);
else
btrfs_qgroup_convert_reserved_meta(node->root,
node->bytes_reserved);
This means, we're always releasing more qgroup metadata rsv than we have
reserved.
This won't trigger selftest warning, as btrfs qgroup metadata rsv has
extra protection against cases like quota enabled half-way.
But we still need to fix this problem any way.
This patch will use the same num_bytes for qgroup metadata rsv so we
could handle it correctly.
Fixes: f218ea6c47 ("btrfs: delayed-inode: Remove wrong qgroup meta reservation calls")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit c6a5d95495 ]
If you replace a seed device in a sprouted fs, it appears to have
successfully replaced the seed device, but if you look closely, it
didn't. Here is an example.
$ mkfs.btrfs /dev/sda
$ btrfstune -S1 /dev/sda
$ mount /dev/sda /btrfs
$ btrfs device add /dev/sdb /btrfs
$ umount /btrfs
$ btrfs device scan --forget
$ mount -o device=/dev/sda /dev/sdb /btrfs
$ btrfs replace start -f /dev/sda /dev/sdc /btrfs
$ echo $?
0
BTRFS info (device sdb): dev_replace from /dev/sda (devid 1) to /dev/sdc started
BTRFS info (device sdb): dev_replace from /dev/sda (devid 1) to /dev/sdc finished
$ btrfs fi show
Label: none uuid: ab2c88b7-be81-4a7e-9849-c3666e7f9f4f
Total devices 2 FS bytes used 256.00KiB
devid 1 size 3.00GiB used 520.00MiB path /dev/sdc
devid 2 size 3.00GiB used 896.00MiB path /dev/sdb
Label: none uuid: 10bd3202-0415-43af-96a8-d5409f310a7e
Total devices 1 FS bytes used 128.00KiB
devid 1 size 3.00GiB used 536.00MiB path /dev/sda
So as per the replace start command and kernel log replace was successful.
Now let's try to clean mount.
$ umount /btrfs
$ btrfs device scan --forget
$ mount -o device=/dev/sdc /dev/sdb /btrfs
mount: /btrfs: wrong fs type, bad option, bad superblock on /dev/sdb, missing codepage or helper program, or other error.
[ 636.157517] BTRFS error (device sdc): failed to read chunk tree: -2
[ 636.180177] BTRFS error (device sdc): open_ctree failed
That's because per dev items it is still looking for the original seed
device.
$ btrfs inspect-internal dump-tree -d /dev/sdb
item 0 key (DEV_ITEMS DEV_ITEM 1) itemoff 16185 itemsize 98
devid 1 total_bytes 3221225472 bytes_used 545259520
io_align 4096 io_width 4096 sector_size 4096 type 0
generation 6 start_offset 0 dev_group 0
seek_speed 0 bandwidth 0
uuid 59368f50-9af2-4b17-91da-8a783cc418d4 <--- seed uuid
fsid 10bd3202-0415-43af-96a8-d5409f310a7e <--- seed fsid
item 1 key (DEV_ITEMS DEV_ITEM 2) itemoff 16087 itemsize 98
devid 2 total_bytes 3221225472 bytes_used 939524096
io_align 4096 io_width 4096 sector_size 4096 type 0
generation 0 start_offset 0 dev_group 0
seek_speed 0 bandwidth 0
uuid 56a0a6bc-4630-4998-8daf-3c3030c4256a <- sprout uuid
fsid ab2c88b7-be81-4a7e-9849-c3666e7f9f4f <- sprout fsid
But the replaced target has the following uuid+fsid in its superblock
which doesn't match with the expected uuid+fsid in its devitem.
$ btrfs in dump-super /dev/sdc | egrep '^generation|dev_item.uuid|dev_item.fsid|devid'
generation 20
dev_item.uuid 59368f50-9af2-4b17-91da-8a783cc418d4
dev_item.fsid ab2c88b7-be81-4a7e-9849-c3666e7f9f4f [match]
dev_item.devid 1
So if you provide the original seed device the mount shall be
successful. Which so long happening in the test case btrfs/163.
$ btrfs device scan --forget
$ mount -o device=/dev/sda /dev/sdb /btrfs
Fix in this patch:
If a seed is not sprouted then there is no replacement of it, because of
its read-only filesystem with a read-only device. Similarly, in the case
of a sprouted filesystem, the seed device is still read only. So, mark
it as you can't replace a seed device, you can only add a new device and
then delete the seed device. If replace is attempted then returns
-EINVAL.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit a30a3d2067 upstream
inc_block_group_ro does a calculation to see if we have enough room left
over if we mark this block group as read only in order to see if it's ok
to mark the block group as read only.
The problem is this calculation _only_ works for data, where our used is
always less than our total. For metadata we will overcommit, so this
will almost always fail for metadata.
Fix this by exporting btrfs_can_overcommit, and then see if we have
enough space to remove the remaining free space in the block group we
are trying to mark read only. If we do then we can mark this block
group as read only.
Reviewed-by: Qu Wenruo <wqu@suse.com>
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: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 9f246926b4 upstream
We have the space_info, we can just check its flags to see if it's the
system chunk space info.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
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: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 6d4572a9d7 upstream.
[BUG]
When the data space is exhausted, even if the inode has NOCOW attribute,
we will still refuse to truncate unaligned range due to ENOSPC.
The following script can reproduce it pretty easily:
#!/bin/bash
dev=/dev/test/test
mnt=/mnt/btrfs
umount $dev &> /dev/null
umount $mnt &> /dev/null
mkfs.btrfs -f $dev -b 1G
mount -o nospace_cache $dev $mnt
touch $mnt/foobar
chattr +C $mnt/foobar
xfs_io -f -c "pwrite -b 4k 0 4k" $mnt/foobar > /dev/null
xfs_io -f -c "pwrite -b 4k 0 1G" $mnt/padding &> /dev/null
sync
xfs_io -c "fpunch 0 2k" $mnt/foobar
umount $mnt
Currently this will fail at the fpunch part.
[CAUSE]
Because btrfs_truncate_block() always reserves space without checking
the NOCOW attribute.
Since the writeback path follows NOCOW bit, we only need to bother the
space reservation code in btrfs_truncate_block().
[FIX]
Make btrfs_truncate_block() follow btrfs_buffered_write() to try to
reserve data space first, and fall back to NOCOW check only when we
don't have enough space.
Such always-try-reserve is an optimization introduced in
btrfs_buffered_write(), to avoid expensive btrfs_check_can_nocow() call.
This patch will export check_can_nocow() as btrfs_check_can_nocow(), and
use it in btrfs_truncate_block() to fix the problem.
Reported-by: Martin Doucha <martin.doucha@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
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: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 260a63395f upstream.
If we attempt to do a RWF_NOWAIT write against a file range for which we
can only do NOCOW for a part of it, due to the existence of holes or
shared extents for example, we proceed with the write as if it were
possible to NOCOW the whole range.
Example:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ touch /mnt/sdj/bar
$ chattr +C /mnt/sdj/bar
$ xfs_io -d -c "pwrite -S 0xab -b 256K 0 256K" /mnt/bar
wrote 262144/262144 bytes at offset 0
256 KiB, 1 ops; 0.0003 sec (694.444 MiB/sec and 2777.7778 ops/sec)
$ xfs_io -c "fpunch 64K 64K" /mnt/bar
$ sync
$ xfs_io -d -c "pwrite -N -V 1 -b 128K -S 0xfe 0 128K" /mnt/bar
wrote 131072/131072 bytes at offset 0
128 KiB, 1 ops; 0.0007 sec (160.051 MiB/sec and 1280.4097 ops/sec)
This last write should fail with -EAGAIN since the file range from 64K to
128K is a hole. On xfs it fails, as expected, but on ext4 it currently
succeeds because apparently it is expensive to check if there are extents
allocated for the whole range, but I'll check with the ext4 people.
Fix the issue by checking if check_can_nocow() returns a number of
NOCOW'able bytes smaller then the requested number of bytes, and if it
does return -EAGAIN.
Fixes: edf064e7c6 ("btrfs: nowait aio support")
CC: stable@vger.kernel.org # 4.14+
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: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6b7faadd98 upstream.
[BUG]
When deleting large files (which cross block group boundary) with
discard mount option, we find some btrfs_discard_extent() calls only
trimmed part of its space, not the whole range:
btrfs_discard_extent: type=0x1 start=19626196992 len=2144530432 trimmed=1073741824 ratio=50%
type: bbio->map_type, in above case, it's SINGLE DATA.
start: Logical address of this trim
len: Logical length of this trim
trimmed: Physically trimmed bytes
ratio: trimmed / len
Thus leaving some unused space not discarded.
[CAUSE]
When discard mount option is specified, after a transaction is fully
committed (super block written to disk), we begin to cleanup pinned
extents in the following call chain:
btrfs_commit_transaction()
|- btrfs_finish_extent_commit()
|- find_first_extent_bit(unpin, 0, &start, &end, EXTENT_DIRTY);
|- btrfs_discard_extent()
However, pinned extents are recorded in an extent_io_tree, which can
merge adjacent extent states.
When a large file gets deleted and it has adjacent file extents across
block group boundary, we will get a large merged range like this:
|<--- BG1 --->|<--- BG2 --->|
|//////|<-- Range to discard --->|/////|
To discard that range, we have the following calls:
btrfs_discard_extent()
|- btrfs_map_block()
| Returned bbio will end at BG1's end. As btrfs_map_block()
| never returns result across block group boundary.
|- btrfs_issuse_discard()
Issue discard for each stripe.
So we will only discard the range in BG1, not the remaining part in BG2.
Furthermore, this bug is not that reliably observed, for above case, if
there is no other extent in BG2, BG2 will be empty and btrfs will trim
all space of BG2, covering up the bug.
[FIX]
- Allow __btrfs_map_block_for_discard() to modify @length parameter
btrfs_map_block() uses its @length paramter to notify the caller how
many bytes are mapped in current call.
With __btrfs_map_block_for_discard() also modifing the @length,
btrfs_discard_extent() now understands when to do extra trim.
- Call btrfs_map_block() in a loop until we hit the range end Since we
now know how many bytes are mapped each time, we can iterate through
each block group boundary and issue correct trim for each range.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2d974619a7 upstream.
The old code goes:
offset = logical - em->start;
length = min_t(u64, em->len - offset, length);
Where @length calculation is dependent on offset, it can take reader
several more seconds to find it's just the same code as:
offset = logical - em->start;
length = min_t(u64, em->start + em->len - logical, length);
Use above code to make the length calculate independent from other
variable, thus slightly increase the readability.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
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: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9722b10148 upstream.
When doing an incremental send and a file has extents shared with itself
at different file offsets, it's possible for send to emit clone operations
that will fail at the destination because the source range goes beyond the
file's current size. This happens when the file size has increased in the
send snapshot, there is a hole between the shared extents and both shared
extents are at file offsets which are greater the file's size in the
parent snapshot.
Example:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt/sdb
$ xfs_io -f -c "pwrite -S 0xf1 0 64K" /mnt/sdb/foobar
$ btrfs subvolume snapshot -r /mnt/sdb /mnt/sdb/base
$ btrfs send -f /tmp/1.snap /mnt/sdb/base
# Create a 320K extent at file offset 512K.
$ xfs_io -c "pwrite -S 0xab 512K 64K" /mnt/sdb/foobar
$ xfs_io -c "pwrite -S 0xcd 576K 64K" /mnt/sdb/foobar
$ xfs_io -c "pwrite -S 0xef 640K 64K" /mnt/sdb/foobar
$ xfs_io -c "pwrite -S 0x64 704K 64K" /mnt/sdb/foobar
$ xfs_io -c "pwrite -S 0x73 768K 64K" /mnt/sdb/foobar
# Clone part of that 320K extent into a lower file offset (192K).
# This file offset is greater than the file's size in the parent
# snapshot (64K). Also the clone range is a bit behind the offset of
# the 320K extent so that we leave a hole between the shared extents.
$ xfs_io -c "reflink /mnt/sdb/foobar 448K 192K 192K" /mnt/sdb/foobar
$ btrfs subvolume snapshot -r /mnt/sdb /mnt/sdb/incr
$ btrfs send -p /mnt/sdb/base -f /tmp/2.snap /mnt/sdb/incr
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt/sdc
$ btrfs receive -f /tmp/1.snap /mnt/sdc
$ btrfs receive -f /tmp/2.snap /mnt/sdc
ERROR: failed to clone extents to foobar: Invalid argument
The problem is that after processing the extent at file offset 256K, which
refers to the first 128K of the 320K extent created by the buffered write
operations, we have 'cur_inode_next_write_offset' set to 384K, which
corresponds to the end offset of the partially shared extent (256K + 128K)
and to the current file size in the receiver. Then when we process the
extent at offset 512K, we do extent backreference iteration to figure out
if we can clone the extent from some other inode or from the same inode,
and we consider the extent at offset 256K of the same inode as a valid
source for a clone operation, which is not correct because at that point
the current file size in the receiver is 384K, which corresponds to the
end of last processed extent (at file offset 256K), so using a clone
source range from 256K to 256K + 320K is invalid because that goes past
the current size of the file (384K) - this makes the receiver get an
-EINVAL error when attempting the clone operation.
So fix this by excluding clone sources that have a range that goes beyond
the current file size in the receiver when iterating extent backreferences.
A test case for fstests follows soon.
Fixes: 11f2069c11 ("Btrfs: send, allow clone operations within the same file")
CC: stable@vger.kernel.org # 5.5+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 11f2069c11 upstream.
For send we currently skip clone operations when the source and
destination files are the same. This is so because clone didn't support
this case in its early days, but support for it was added back in May
2013 by commit a96fbc7288 ("Btrfs: allow file data clone within a
file"). This change adds support for it.
Example:
$ mkfs.btrfs -f /dev/sdd
$ mount /dev/sdd /mnt/sdd
$ xfs_io -f -c "pwrite -S 0xab -b 64K 0 64K" /mnt/sdd/foobar
$ xfs_io -c "reflink /mnt/sdd/foobar 0 64K 64K" /mnt/sdd/foobar
$ btrfs subvolume snapshot -r /mnt/sdd /mnt/sdd/snap
$ mkfs.btrfs -f /dev/sde
$ mount /dev/sde /mnt/sde
$ btrfs send /mnt/sdd/snap | btrfs receive /mnt/sde
Without this change file foobar at the destination has a single 128Kb
extent:
$ filefrag -v /mnt/sde/snap/foobar
Filesystem type is: 9123683e
File size of /mnt/sde/snap/foobar is 131072 (32 blocks of 4096 bytes)
ext: logical_offset: physical_offset: length: expected: flags:
0: 0.. 31: 0.. 31: 32: last,unknown_loc,delalloc,eof
/mnt/sde/snap/foobar: 1 extent found
With this we get a single 64Kb extent that is shared at file offsets 0
and 64K, just like in the source filesystem:
$ filefrag -v /mnt/sde/snap/foobar
Filesystem type is: 9123683e
File size of /mnt/sde/snap/foobar is 131072 (32 blocks of 4096 bytes)
ext: logical_offset: physical_offset: length: expected: flags:
0: 0.. 15: 3328.. 3343: 16: shared
1: 16.. 31: 3328.. 3343: 16: 3344: last,shared,eof
/mnt/sde/snap/foobar: 2 extents found
Reviewed-by: Josef Bacik <josef@toxicpanda.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: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4c8f353272 upstream.
We use a device's allocation state tree to track ranges in a device used
for allocated chunks, and we set ranges in this tree when allocating a new
chunk. However after a device replace operation, we were not setting the
allocated ranges in the new device's allocation state tree, so that tree
is empty after a device replace.
This means that a fitrim operation after a device replace will trim the
device ranges that have allocated chunks and extents, as we trim every
range for which there is not a range marked in the device's allocation
state tree. It is also important during chunk allocation, since the
device's allocation state is used to determine if a range is already
allocated when allocating a new chunk.
This is trivial to reproduce and the following script triggers the bug:
$ cat reproducer.sh
#!/bin/bash
DEV1="/dev/sdg"
DEV2="/dev/sdh"
DEV3="/dev/sdi"
wipefs -a $DEV1 $DEV2 $DEV3 &> /dev/null
# Create a raid1 test fs on 2 devices.
mkfs.btrfs -f -m raid1 -d raid1 $DEV1 $DEV2 > /dev/null
mount $DEV1 /mnt/btrfs
xfs_io -f -c "pwrite -S 0xab 0 10M" /mnt/btrfs/foo
echo "Starting to replace $DEV1 with $DEV3"
btrfs replace start -B $DEV1 $DEV3 /mnt/btrfs
echo
echo "Running fstrim"
fstrim /mnt/btrfs
echo
echo "Unmounting filesystem"
umount /mnt/btrfs
echo "Mounting filesystem in degraded mode using $DEV3 only"
wipefs -a $DEV1 $DEV2 &> /dev/null
mount -o degraded $DEV3 /mnt/btrfs
if [ $? -ne 0 ]; then
dmesg | tail
echo
echo "Failed to mount in degraded mode"
exit 1
fi
echo
echo "File foo data (expected all bytes = 0xab):"
od -A d -t x1 /mnt/btrfs/foo
umount /mnt/btrfs
When running the reproducer:
$ ./replace-test.sh
wrote 10485760/10485760 bytes at offset 0
10 MiB, 2560 ops; 0.0901 sec (110.877 MiB/sec and 28384.5216 ops/sec)
Starting to replace /dev/sdg with /dev/sdi
Running fstrim
Unmounting filesystem
Mounting filesystem in degraded mode using /dev/sdi only
mount: /mnt/btrfs: wrong fs type, bad option, bad superblock on /dev/sdi, missing codepage or helper program, or other error.
[19581.748641] BTRFS info (device sdg): dev_replace from /dev/sdg (devid 1) to /dev/sdi started
[19581.803842] BTRFS info (device sdg): dev_replace from /dev/sdg (devid 1) to /dev/sdi finished
[19582.208293] BTRFS info (device sdi): allowing degraded mounts
[19582.208298] BTRFS info (device sdi): disk space caching is enabled
[19582.208301] BTRFS info (device sdi): has skinny extents
[19582.212853] BTRFS warning (device sdi): devid 2 uuid 1f731f47-e1bb-4f00-bfbb-9e5a0cb4ba9f is missing
[19582.213904] btree_readpage_end_io_hook: 25839 callbacks suppressed
[19582.213907] BTRFS error (device sdi): bad tree block start, want 30490624 have 0
[19582.214780] BTRFS warning (device sdi): failed to read root (objectid=7): -5
[19582.231576] BTRFS error (device sdi): open_ctree failed
Failed to mount in degraded mode
So fix by setting all allocated ranges in the replace target device when
the replace operation is finishing, when we are holding the chunk mutex
and we can not race with new chunk allocations.
A test case for fstests follows soon.
Fixes: 1c11b63eff ("btrfs: replace pending/pinned chunks lists with io tree")
CC: stable@vger.kernel.org # 5.2+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fa91e4aa17 ]
[BUG]
When running tests like generic/013 on test device with btrfs quota
enabled, it can normally lead to data leak, detected at unmount time:
BTRFS warning (device dm-3): qgroup 0/5 has unreleased space, type 0 rsv 4096
------------[ cut here ]------------
WARNING: CPU: 11 PID: 16386 at fs/btrfs/disk-io.c:4142 close_ctree+0x1dc/0x323 [btrfs]
RIP: 0010:close_ctree+0x1dc/0x323 [btrfs]
Call Trace:
btrfs_put_super+0x15/0x17 [btrfs]
generic_shutdown_super+0x72/0x110
kill_anon_super+0x18/0x30
btrfs_kill_super+0x17/0x30 [btrfs]
deactivate_locked_super+0x3b/0xa0
deactivate_super+0x40/0x50
cleanup_mnt+0x135/0x190
__cleanup_mnt+0x12/0x20
task_work_run+0x64/0xb0
__prepare_exit_to_usermode+0x1bc/0x1c0
__syscall_return_slowpath+0x47/0x230
do_syscall_64+0x64/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
---[ end trace caf08beafeca2392 ]---
BTRFS error (device dm-3): qgroup reserved space leaked
[CAUSE]
In the offending case, the offending operations are:
2/6: writev f2X[269 1 0 0 0 0] [1006997,67,288] 0
2/7: truncate f2X[269 1 0 0 48 1026293] 18388 0
The following sequence of events could happen after the writev():
CPU1 (writeback) | CPU2 (truncate)
-----------------------------------------------------------------
btrfs_writepages() |
|- extent_write_cache_pages() |
|- Got page for 1003520 |
| 1003520 is Dirty, no writeback |
| So (!clear_page_dirty_for_io()) |
| gets called for it |
|- Now page 1003520 is Clean. |
| | btrfs_setattr()
| | |- btrfs_setsize()
| | |- truncate_setsize()
| | New i_size is 18388
|- __extent_writepage() |
| |- page_offset() > i_size |
|- btrfs_invalidatepage() |
|- Page is clean, so no qgroup |
callback executed
This means, the qgroup reserved data space is not properly released in
btrfs_invalidatepage() as the page is Clean.
[FIX]
Instead of checking the dirty bit of a page, call
btrfs_qgroup_free_data() unconditionally in btrfs_invalidatepage().
As qgroup rsv are completely bound to the QGROUP_RESERVED bit of
io_tree, not bound to page status, thus we won't cause double freeing
anyway.
Fixes: 0b34c261e2 ("btrfs: qgroup: Prevent qgroup->reserved from going subzero")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.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 c36cac28cb ]
In btrfs_submit_direct(), if we fail to allocate the btrfs_dio_private,
we complete the ordered extent range. However, we don't mark that the
range doesn't need to be cleaned up from btrfs_direct_IO() until later.
Therefore, if we fail to allocate the btrfs_dio_private, we complete the
ordered extent range twice. We could fix this by updating
unsubmitted_oe_range earlier, but it's cleaner to reorganize the code so
that creating the btrfs_dio_private and submitting the bios are
separate, and once the btrfs_dio_private is created, cleanup always
happens through the btrfs_dio_private.
The logic around unsubmitted_oe_range_end and unsubmitted_oe_range_start
is really subtle. We have the following:
1. btrfs_direct_IO sets those two to the same value.
2. When we call __blockdev_direct_IO unless
btrfs_get_blocks_direct->btrfs_get_blocks_direct_write is called to
modify unsubmitted_oe_range_start so that start < end. Cleanup
won't happen.
3. We come into btrfs_submit_direct - if it dip allocation fails we'd
return with oe_range_end now modified so cleanup will happen.
4. If we manage to allocate the dip we reset the unsubmitted range
members to be equal so that cleanup happens from
btrfs_endio_direct_write.
This 4-step logic is not really obvious, especially given it's scattered
across 3 functions.
Fixes: f28a492878 ("Btrfs: fix leaking of ordered extents after direct IO write error")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
[ add range start/end logic explanation from Nikolay ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7c09c03091 ]
Deleting a subvolume on a full filesystem leads to ENOSPC followed by a
forced read-only. This is not a transaction abort and the filesystem is
otherwise ok, so the error should be just propagated to the callers.
This is caused by unnecessary call to btrfs_handle_fs_error for all
errors, except EAGAIN. This does not make sense as the standard
transaction abort mechanism is in btrfs_drop_snapshot so all relevant
failures are handled.
Originally in commit cb1b69f450 ("Btrfs: forced readonly when
btrfs_drop_snapshot() fails") there was no return value at all, so the
btrfs_std_error made some sense but once the error handling and
propagation has been implemented we don't need it anymore.
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit aec7db3b13 ]
I made a mistake with my previous fix, I assumed that we didn't need to
mess with the reloc roots once we were out of the part of relocation where
we are actually moving the extents.
The subtle thing that I missed is that btrfs_init_reloc_root() also
updates the last_trans for the reloc root when we do
btrfs_record_root_in_trans() for the corresponding fs_root. I've added a
comment to make sure future me doesn't make this mistake again.
This showed up as a WARN_ON() in btrfs_copy_root() because our
last_trans didn't == the current transid. This could happen if we
snapshotted a fs root with a reloc root after we set
rc->create_reloc_tree = 0, but before we actually merge the reloc root.
Worth mentioning that the regression produced the following warning
when running snapshot creation and balance in parallel:
BTRFS info (device sdc): relocating block group 30408704 flags metadata|dup
------------[ cut here ]------------
WARNING: CPU: 0 PID: 12823 at fs/btrfs/ctree.c:191 btrfs_copy_root+0x26f/0x430 [btrfs]
CPU: 0 PID: 12823 Comm: btrfs Tainted: G W 5.6.0-rc7-btrfs-next-58 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
RIP: 0010:btrfs_copy_root+0x26f/0x430 [btrfs]
RSP: 0018:ffffb96e044279b8 EFLAGS: 00010202
RAX: 0000000000000009 RBX: ffff9da70bf61000 RCX: ffffb96e04427a48
RDX: ffff9da733a770c8 RSI: ffff9da70bf61000 RDI: ffff9da694163818
RBP: ffff9da733a770c8 R08: fffffffffffffff8 R09: 0000000000000002
R10: ffffb96e044279a0 R11: 0000000000000000 R12: ffff9da694163818
R13: fffffffffffffff8 R14: ffff9da6d2512000 R15: ffff9da714cdac00
FS: 00007fdeacf328c0(0000) GS:ffff9da735e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a2a5b8a118 CR3: 00000001eed78002 CR4: 00000000003606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
? create_reloc_root+0x49/0x2b0 [btrfs]
? kmem_cache_alloc_trace+0xe5/0x200
create_reloc_root+0x8b/0x2b0 [btrfs]
btrfs_reloc_post_snapshot+0x96/0x5b0 [btrfs]
create_pending_snapshot+0x610/0x1010 [btrfs]
create_pending_snapshots+0xa8/0xd0 [btrfs]
btrfs_commit_transaction+0x4c7/0xc50 [btrfs]
? btrfs_mksubvol+0x3cd/0x560 [btrfs]
btrfs_mksubvol+0x455/0x560 [btrfs]
__btrfs_ioctl_snap_create+0x15f/0x190 [btrfs]
btrfs_ioctl_snap_create_v2+0xa4/0xf0 [btrfs]
? mem_cgroup_commit_charge+0x6e/0x540
btrfs_ioctl+0x12d8/0x3760 [btrfs]
? do_raw_spin_unlock+0x49/0xc0
? _raw_spin_unlock+0x29/0x40
? __handle_mm_fault+0x11b3/0x14b0
? ksys_ioctl+0x92/0xb0
ksys_ioctl+0x92/0xb0
? trace_hardirqs_off_thunk+0x1a/0x1c
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x5c/0x280
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fdeabd3bdd7
Fixes: 2abc726ab4 ("btrfs: do not init a reloc root if we aren't relocating")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1a0afa0ecf ]
If we have an error while processing the reloc roots we could leak roots
that were added to rc->reloc_roots before we hit the error. We could
have also not removed the reloc tree mapping from our rb_tree, so clean
up any remaining nodes in the reloc root rb_tree.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ use rbtree_postorder_for_each_entry_safe ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2abc726ab4 ]
We previously were checking if the root had a dead root before accessing
root->reloc_root in order to avoid a use-after-free type bug. However
this scenario happens after we've unset the reloc control, so we would
have been saved if we'd simply checked for fs_info->reloc_control. At
this point during relocation we no longer need to be creating new reloc
roots, so simply move this check above the reloc_root checks to avoid
any future races and confusion.
Reviewed-by: Qu Wenruo <wqu@suse.com>
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>
Filipe Manana