commit 3b50086f0c0d78c144d9483fa292c1509c931b70 upstream.

For VFS listxattr calls, xfs_xattr_put_listent calls
__xfs_xattr_put_listent twice if it sees an attribute
"trusted.SGI_ACL_FILE": once for that name, and again for
"system.posix_acl_access".  Unfortunately, if we happen to run out of
buffer space while emitting the first name, we set count to -1 (so that
we can feed ERANGE to the caller).  The second invocation doesn't check that
the context parameters make sense and overwrites the byte before the
buffer, triggering a KASAN report:

==================================================================
BUG: KASAN: slab-out-of-bounds in strncpy+0xb3/0xd0
Write of size 1 at addr ffff88807fbd317f by task syz/1113

CPU: 3 PID: 1113 Comm: syz Not tainted 5.0.0-rc6-xfsx #rc6
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
 dump_stack+0xcc/0x180
 print_address_description+0x6c/0x23c
 kasan_report.cold.3+0x1c/0x35
 strncpy+0xb3/0xd0
 __xfs_xattr_put_listent+0x1a9/0x2c0 [xfs]
 xfs_attr_list_int_ilocked+0x11af/0x1800 [xfs]
 xfs_attr_list_int+0x20c/0x2e0 [xfs]
 xfs_vn_listxattr+0x225/0x320 [xfs]
 listxattr+0x11f/0x1b0
 path_listxattr+0xbd/0x130
 do_syscall_64+0x139/0x560

While we're at it we add an assert to the other put_listent to avoid
this sort of thing ever happening to the attrlist_by_handle code.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJiufei Xue <jiufei.xue@linux.alibaba.com>
Acked-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

commit aa6ee4ab69293969867ab09b57546d226ace3d7a upstream.

The cached writeback mapping is EOF trimmed to try and avoid races
between post-eof block management and writeback that result in
sending cached data to a stale location. The cached mapping is
currently trimmed on the validation check, which leaves a race
window between the time the mapping is cached and when it is trimmed
against the current inode size.

For example, if a new mapping is cached by delalloc conversion on a
blocksize == page size fs, we could cycle various locks, perform
memory allocations, etc.  in the writeback codepath before the
associated mapping is eventually trimmed to i_size. This leaves
enough time for a post-eof truncate and file append before the
cached mapping is trimmed. The former event essentially invalidates
a range of the cached mapping and the latter bumps the inode size
such the trim on the next writepage event won't trim all of the
invalid blocks. fstest generic/464 reproduces this scenario
occasionally and causes a lost writeback and stale delalloc blocks
warning on inode inactivation.

To work around this problem, trim the cached writeback mapping as
soon as it is cached in addition to on subsequent validation checks.
This is a minor tweak to tighten the race window as much as possible
until a proper invalidation mechanism is available.

Fixes: 40214d12 ("xfs: trim writepage mapping to within eof")
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NAllison Henderson <allison.henderson@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 7d048df4e9b05ba89b74d062df59498aa81f3785 upstream.

xfs_btree_sblock_verify_crc is a bool so should not be returning
a failaddr_t; worse, if xfs_log_check_lsn fails it returns
__this_address which looks like a boolean true (i.e. success)
to the caller.

(interestingly xfs_btree_lblock_verify_crc doesn't have the issue)
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

commit a579121f94aba4e8bad1a121a0fad050d6925296 upstream.

In commit e53c4b59, I *tried* to teach xfs to force writeback when we
fzero/fpunch right up to EOF so that if EOF is in the middle of a page,
the post-EOF part of the page gets zeroed before we return to userspace.
Unfortunately, I missed the part where PAGE_MASK is ~(PAGE_SIZE - 1),
which means that we totally fail to zero if we're fpunching and EOF is
within the first page.  Worse yet, the same PAGE_MASK thinko plagues the
filemap_write_and_wait_range call, so we'd initiate writeback of the
entire file, which (mostly) masked the thinko.

Drop the tricky PAGE_MASK and replace it with correct usage of PAGE_SIZE
and the proper rounding macros.

Fixes: e53c4b59 ("xfs: ensure post-EOF zeroing happens after zeroing part of a file")
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

commit de7243057e7cefa923fa5f467c0f1ec24eef41d2 upsream.

When project is set, we should use inode limit minus the used count
Signed-off-by: NYe Yin <dbyin@tencent.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

commit 9230a0b65b47fe6856c4468ec0175c4987e5bede upstream.

Long saga. There have been days spent following this through dead end
after dead end in multi-GB event traces. This morning, after writing
a trace-cmd wrapper that enabled me to be more selective about XFS
trace points, I discovered that I could get just enough essential
tracepoints enabled that there was a 50:50 chance the fsx config
would fail at ~115k ops. If it didn't fail at op 115547, I stopped
fsx at op 115548 anyway.

That gave me two traces - one where the problem manifested, and one
where it didn't. After refining the traces to have the necessary
information, I found that in the failing case there was a real
extent in the COW fork compared to an unwritten extent in the
working case.

Walking back through the two traces to the point where the CWO fork
extents actually diverged, I found that the bad case had an extra
unwritten extent in it. This is likely because the bug it led me to
had triggered multiple times in those 115k ops, leaving stray
COW extents around. What I saw was a COW delalloc conversion to an
unwritten extent (as they should always be through
xfs_iomap_write_allocate()) resulted in a /written extent/:

xfs_writepage:        dev 259:0 ino 0x83 pgoff 0x17000 size 0x79a00 offset 0 length 0
xfs_iext_remove:      dev 259:0 ino 0x83 state RC|LF|RF|COW cur 0xffff888247b899c0/2 offset 32 block 152 count 20 flag 1 caller xfs_bmap_add_extent_delay_real
xfs_bmap_pre_update:  dev 259:0 ino 0x83 state RC|LF|RF|COW cur 0xffff888247b899c0/1 offset 1 block 4503599627239429 count 31 flag 0 caller xfs_bmap_add_extent_delay_real
xfs_bmap_post_update: dev 259:0 ino 0x83 state RC|LF|RF|COW cur 0xffff888247b899c0/1 offset 1 block 121 count 51 flag 0 caller xfs_bmap_add_ex

Basically, Cow fork before:

	0 1            32          52
	+H+DDDDDDDDDDDD+UUUUUUUUUUU+
	   PREV		RIGHT

COW delalloc conversion allocates:

	  1	       32
	  +uuuuuuuuuuuu+
	  NEW

And the result according to the xfs_bmap_post_update trace was:

	0 1            32          52
	+H+wwwwwwwwwwwwwwwwwwwwwwww+
	   PREV

Which is clearly wrong - it should be a merged unwritten extent,
not an unwritten extent.

That lead me to look at the LEFT_FILLING|RIGHT_FILLING|RIGHT_CONTIG
case in xfs_bmap_add_extent_delay_real(), and sure enough, there's
the bug.

It takes the old delalloc extent (PREV) and adds the length of the
RIGHT extent to it, takes the start block from NEW, removes the
RIGHT extent and then updates PREV with the new extent.

What it fails to do is update PREV.br_state. For delalloc, this is
always XFS_EXT_NORM, while in this case we are converting the
delayed allocation to unwritten, so it needs to be updated to
XFS_EXT_UNWRITTEN. This LF|RF|RC case does not do this, and so
the resultant extent is always written.

And that's the bug I've been chasing for a week - a bmap btree bug,
not a reflink/dedupe/copy_file_range bug, but a BMBT bug introduced
with the recent in core extent tree scalability enhancements.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

commit d43aaf1685aa471f0593685c9f54d53e3af3cf3f upstream.

When retrying a failed inode or dquot buffer,
xfs_buf_resubmit_failed_buffers() clears all the failed flags from
the inde/dquot log items. In doing so, it also drops all the
reference counts on the buffer that the failed log items hold. This
means it can drop all the active references on the buffer and hence
free the buffer before it queues it for write again.

Putting the buffer on the delwri queue takes a reference to the
buffer (so that it hangs around until it has been written and
completed), but this goes bang if the buffer has already been freed.

Hence we need to add the buffer to the delwri queue before we remove
the failed flags from the log items attached to the buffer to ensure
it always remains referenced during the resubmit process.
Reported-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

commit 59e4293149106fb92530f8e56fa3992d8548c5e6 upstream.

Page writeback indirectly handles shared extents via the existence
of overlapping COW fork blocks. If COW fork blocks exist, writeback
always performs the associated copy-on-write regardless if the
underlying blocks are actually shared. If the blocks are shared,
then overlapping COW fork blocks must always exist.

fstests shared/010 reproduces a case where a buffered write occurs
over a shared block without performing the requisite COW fork
reservation.  This ultimately causes writeback to the shared extent
and data corruption that is detected across md5 checks of the
filesystem across a mount cycle.

The problem occurs when a buffered write lands over a shared extent
that crosses an extent size hint boundary and that also happens to
have a partial COW reservation that doesn't cover the start and end
blocks of the data fork extent.

For example, a buffered write occurs across the file offset (in FSB
units) range of [29, 57]. A shared extent exists at blocks [29, 35]
and COW reservation already exists at blocks [32, 34]. After
accommodating a COW extent size hint of 32 blocks and the existing
reservation at offset 32, xfs_reflink_reserve_cow() allocates 32
blocks of reservation at offset 0 and returns with COW reservation
across the range of [0, 34]. The associated data fork extent is
still [29, 35], however, which isn't fully covered by the COW
reservation.

This leads to a buffered write at file offset 35 over a shared
extent without associated COW reservation. Writeback eventually
kicks in, performs an overwrite of the underlying shared block and
causes the associated data corruption.

Update xfs_reflink_reserve_cow() to accommodate the fact that a
delalloc allocation request may not fully cover the extent in the
data fork. Trim the data fork extent appropriately, just as is done
for shared extent boundaries and/or existing COW reservations that
happen to overlap the start of the data fork extent. This prevents
shared/010 failures due to data corruption on reflink enabled
filesystems.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

commit 837514f7a4ca4aca06aec5caa5ff56d33ef06976 upstream.

generic/070 on 64k block size filesystems is failing with a verifier
corruption on writeback or an attribute leaf block:

[   94.973083] XFS (pmem0): Metadata corruption detected at xfs_attr3_leaf_verify+0x246/0x260, xfs_attr3_leaf block 0x811480
[   94.975623] XFS (pmem0): Unmount and run xfs_repair
[   94.976720] XFS (pmem0): First 128 bytes of corrupted metadata buffer:
[   94.978270] 000000004b2e7b45: 00 00 00 00 00 00 00 00 3b ee 00 00 00 00 00 00  ........;.......
[   94.980268] 000000006b1db90b: 00 00 00 00 00 81 14 80 00 00 00 00 00 00 00 00  ................
[   94.982251] 00000000433f2407: 22 7b 5c 82 2d 5c 47 4c bb 31 1c 37 fa a9 ce d6  "{\.-\GL.1.7....
[   94.984157] 0000000010dc7dfb: 00 00 00 00 00 81 04 8a 00 0a 18 e8 dd 94 01 00  ................
[   94.986215] 00000000d5a19229: 00 a0 dc f4 fe 98 01 68 f0 d8 07 e0 00 00 00 00  .......h........
[   94.988171] 00000000521df36c: 0c 2d 32 e2 fe 20 01 00 0c 2d 58 65 fe 0c 01 00  .-2.. ...-Xe....
[   94.990162] 000000008477ae06: 0c 2d 5b 66 fe 8c 01 00 0c 2d 71 35 fe 7c 01 00  .-[f.....-q5.|..
[   94.992139] 00000000a4a6bca6: 0c 2d 72 37 fc d4 01 00 0c 2d d8 b8 f0 90 01 00  .-r7.....-......
[   94.994789] XFS (pmem0): xfs_do_force_shutdown(0x8) called from line 1453 of file fs/xfs/xfs_buf.c. Return address = ffffffff815365f3

This is failing this check:

                end = ichdr.freemap[i].base + ichdr.freemap[i].size;
                if (end < ichdr.freemap[i].base)
>>>>>                   return __this_address;
                if (end > mp->m_attr_geo->blksize)
                        return __this_address;

And from the buffer output above, the freemap array is:

	freemap[0].base = 0x00a0
	freemap[0].size = 0xdcf4	end = 0xdd94
	freemap[1].base = 0xfe98
	freemap[1].size = 0x0168	end = 0x10000
	freemap[2].base = 0xf0d8
	freemap[2].size = 0x07e0	end = 0xf8b8

These all look valid - the block size is 0x10000 and so from the
last check in the above verifier fragment we know that the end
of freemap[1] is valid. The problem is that end is declared as:

	uint16_t	end;

And (uint16_t)0x10000 = 0. So we have a verifier bug here, not a
corruption. Fix the verifier to use uint32_t types for the check and
hence avoid the overflow.

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=201577Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

commit 132bf6723749f7219c399831eeb286dbbb985429 upstream.

In this function, once 'buf' has been allocated, we unconditionally
return 0.
However, 'error' is set to some error codes in several error handling
paths.
Before commit 232b5194 ("xfs: simplify the xfs_getbmap interface")
this was not an issue because all error paths were returning directly,
but now that some cleanup at the end may be needed, we must propagate the
error code.

Fixes: 232b5194 ("xfs: simplify the xfs_getbmap interface")
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

commit 96987eea537d6ccd98704a71958f9ba02da80843 upstream.

We need to make sure we have no outstanding COW blocks before we swap
extents, as there is nothing preventing us from having preallocated COW
delalloc on either inode that swapext is called on.  That case can
easily be reproduced by running generic/324 in always_cow mode:

[  620.760572] XFS: Assertion failed: tip->i_delayed_blks == 0, file: fs/xfs/xfs_bmap_util.c, line: 1669
[  620.761608] ------------[ cut here ]------------
[  620.762171] kernel BUG at fs/xfs/xfs_message.c:102!
[  620.762732] invalid opcode: 0000 [#1] SMP PTI
[  620.763272] CPU: 0 PID: 24153 Comm: xfs_fsr Tainted: G        W         4.19.0-rc1+ #4182
[  620.764203] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.1-1 04/01/2014
[  620.765202] RIP: 0010:assfail+0x20/0x28
[  620.765646] Code: 31 ff e8 83 fc ff ff 0f 0b c3 48 89 f1 41 89 d0 48 c7 c6 48 ca 8d 82 48 89 fa 38
[  620.767758] RSP: 0018:ffffc9000898bc10 EFLAGS: 00010202
[  620.768359] RAX: 0000000000000000 RBX: ffff88012f14ba40 RCX: 0000000000000000
[  620.769174] RDX: 00000000ffffffc0 RSI: 000000000000000a RDI: ffffffff828560d9
[  620.769982] RBP: ffff88012f14b300 R08: 0000000000000000 R09: 0000000000000000
[  620.770788] R10: 000000000000000a R11: f000000000000000 R12: ffffc9000898bc98
[  620.771638] R13: ffffc9000898bc9c R14: ffff880130b5e2b8 R15: ffff88012a1fa2a8
[  620.772504] FS:  00007fdc36e0fbc0(0000) GS:ffff88013ba00000(0000) knlGS:0000000000000000
[  620.773475] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  620.774168] CR2: 00007fdc3604d000 CR3: 0000000132afc000 CR4: 00000000000006f0
[  620.774978] Call Trace:
[  620.775274]  xfs_swap_extent_forks+0x2a0/0x2e0
[  620.775792]  xfs_swap_extents+0x38b/0xab0
[  620.776256]  xfs_ioc_swapext+0x121/0x140
[  620.776709]  xfs_file_ioctl+0x328/0xc90
[  620.777154]  ? rcu_read_lock_sched_held+0x50/0x60
[  620.777694]  ? xfs_iunlock+0x233/0x260
[  620.778127]  ? xfs_setattr_nonsize+0x3be/0x6a0
[  620.778647]  do_vfs_ioctl+0x9d/0x680
[  620.779071]  ? ksys_fchown+0x47/0x80
[  620.779552]  ksys_ioctl+0x35/0x70
[  620.780040]  __x64_sys_ioctl+0x11/0x20
[  620.780530]  do_syscall_64+0x4b/0x190
[  620.780927]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  620.781467] RIP: 0033:0x7fdc364d0f07
[  620.781900] Code: b3 66 90 48 8b 05 81 5f 2c 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 28
[  620.784044] RSP: 002b:00007ffe2a766038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[  620.784896] RAX: ffffffffffffffda RBX: 0000000000000025 RCX: 00007fdc364d0f07
[  620.785667] RDX: 0000560296ca2fc0 RSI: 00000000c0c0586d RDI: 0000000000000005
[  620.786398] RBP: 0000000000000025 R08: 0000000000001200 R09: 0000000000000000
[  620.787283] R10: 0000000000000432 R11: 0000000000000246 R12: 0000000000000005
[  620.788051] R13: 0000000000000000 R14: 0000000000001000 R15: 0000000000000006
[  620.788927] Modules linked in:
[  620.789340] ---[ end trace 9503b7417ffdbdb0 ]---
[  620.790065] RIP: 0010:assfail+0x20/0x28
[  620.790642] Code: 31 ff e8 83 fc ff ff 0f 0b c3 48 89 f1 41 89 d0 48 c7 c6 48 ca 8d 82 48 89 fa 38
[  620.793038] RSP: 0018:ffffc9000898bc10 EFLAGS: 00010202
[  620.793609] RAX: 0000000000000000 RBX: ffff88012f14ba40 RCX: 0000000000000000
[  620.794317] RDX: 00000000ffffffc0 RSI: 000000000000000a RDI: ffffffff828560d9
[  620.795025] RBP: ffff88012f14b300 R08: 0000000000000000 R09: 0000000000000000
[  620.795778] R10: 000000000000000a R11: f000000000000000 R12: ffffc9000898bc98
[  620.796675] R13: ffffc9000898bc9c R14: ffff880130b5e2b8 R15: ffff88012a1fa2a8
[  620.797782] FS:  00007fdc36e0fbc0(0000) GS:ffff88013ba00000(0000) knlGS:0000000000000000
[  620.798908] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  620.799594] CR2: 00007fdc3604d000 CR3: 0000000132afc000 CR4: 00000000000006f0
[  620.800424] Kernel panic - not syncing: Fatal exception
[  620.801191] Kernel Offset: disabled
[  620.801597] ---[ end Kernel panic - not syncing: Fatal exception ]---
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

commit 41657e5507b13e963be906d5d874f4f02374fd5c upstream.

The addition of FIBT, RMAP and REFCOUNT changed the offsets into
__xfssats structure.

This caused xqmstat_proc_show() to display garbage data via
/proc/fs/xfs/xqmstat, once it relies on the offsets marked via macros.

Fix it.

Fixes: 00f4e4f9 xfs: add rmap btree stats infrastructure
Fixes: aafc3c24 xfs: support the XFS_BTNUM_FINOBT free inode btree type
Fixes: 46eeb521 xfs: introduce refcount btree definitions
Signed-off-by: NCarlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>

When reflinking sub-file ranges, a data corruption can occur when
the source file range includes a partial EOF block. This shares the
unknown data beyond EOF into the second file at a position inside
EOF, exposing stale data in the second file.

XFS only supports whole block sharing, but we still need to
support whole file reflink correctly.  Hence if the reflink
request includes the last block of the souce file, only proceed with
the reflink operation if it lands at or past the destination file's
current EOF. If it lands within the destination file EOF, reject the
entire request with -EINVAL and make the caller go the hard way.

This avoids the data corruption vector, but also avoids disruption
of returning EINVAL to userspace for the common case of whole file
cloning.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

A deduplication data corruption is Exposed by fstests generic/505 on
XFS. It is caused by extending the block match range to include the
partial EOF block, but then allowing unknown data beyond EOF to be
considered a "match" to data in the destination file because the
comparison is only made to the end of the source file. This corrupts
the destination file when the source extent is shared with it.

XFS only supports whole block dedupe, but we still need to appear to
support whole file dedupe correctly.  Hence if the dedupe request
includes the last block of the souce file, don't include it in the
actual XFS dedupe operation. If the rest of the range dedupes
successfully, then report the partial last block as deduped, too, so
that userspace sees it as a successful dedupe rather than return
EINVAL because we can't dedupe unaligned blocks.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Before cloning into a file, update the ctime and remove sensitive
attributes like suid, just like we'd do for a regular file write.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

When we're reflinking between two files and the destination file range
is well beyond the destination file's EOF marker, zero any posteof
speculative preallocations in the destination file so that we don't
expose stale disk contents.  The previous strategy of trying to clear
the preallocations does not work if the destination file has the
PREALLOC flag set.

Uncovered by shared/010.
Reported-by: NZorro Lang <zlang@redhat.com>
Bugzilla-id: https://bugzilla.kernel.org/show_bug.cgi?id=201259Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Refactor all the reflink preparation steps into a separate helper
that we'll use to land all the upcoming fixes for insufficient input
checks.

This rework also moves the invalidation of the destination range to
the prep function so that it is done before the range is remapped.
This ensures that nobody can access the data in range being remapped
until the remap is complete.

[dgc: fix xfs_reflink_remap_prep() return value and caller check to
handle vfs_clone_file_prep_inodes() returning 0 to mean "nothing to
do". ]

[dgc: make sure length changed by vfs_clone_file_prep_inodes() gets
propagated back to XFS code that does the remapping. ]
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Commit 01239d77 ("xfs: fix a null pointer dereference in
xfs_bmap_extents_to_btree") attempted to fix a null pointer
dreference when a fuzzing corruption of some kind was found.
This fix was flawed, resulting in assert failures like:

XFS: Assertion failed: ifp->if_broot == NULL, file: fs/xfs/libxfs/xfs_bmap.c, line: 715
.....
Call Trace:
  xfs_bmap_extents_to_btree+0x6b9/0x7b0
  __xfs_bunmapi+0xae7/0xf00
  ? xfs_log_reserve+0x1c8/0x290
  xfs_reflink_remap_extent+0x20b/0x620
  xfs_reflink_remap_blocks+0x7e/0x290
  xfs_reflink_remap_range+0x311/0x530
  vfs_dedupe_file_range_one+0xd7/0xe0
  vfs_dedupe_file_range+0x15b/0x1a0
  do_vfs_ioctl+0x267/0x6c0

The problem is that the error handling code now asserts that the
inode fork is not in btree format before the error handling code
undoes the modifications that put the fork back in extent format.
Fix this by moving the assert back to after the xfs_iroot_realloc()
call that returns the fork to extent format, and clean up the jump
labels to be meaningful.

Also, returning ENOSPC when xfs_btree_get_bufl() fails to
instantiate the buffer that was allocated (the actual fix in the
commit mentioned above) is incorrect. This is a fatal error - only
an invalid block address or a filesystem shutdown can result in
failing to get a buffer here.

Hence change this to EFSCORRUPTED so that the higher layer knows
this was a corruption related failure and should not treat it as an
ENOSPC error.  This should result in a shutdown (via cancelling a
dirty transaction) which is necessary as we do not attempt to clean
up the (invalid) block that we have already allocated.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

One of the first steps of log recovery is to check for the special
case of a zeroed log. If the first cycle in the log is zero or the
tail portion of the log is zeroed, the head is set to the first
instance of cycle 0. xlog_find_zeroed() includes a sanity check that
enforces that the first cycle in the log must be 1 if the last cycle
is 0. While this is true in most cases, the check is not totally
valid because it doesn't consider the case where the filesystem
crashed after a partial/out of order log buffer completion that
wraps around the end of the physical log.

For example, consider a filesystem that has completed most of the
first cycle of the log, reaches the end of the physical log and
splits the next single log buffer write into two in order to wrap
around the end of the log. If these I/Os are reordered, the second
(wrapped) I/O completes and the first happens to fail, the log is
left in a state where the last cycle of the log is 0 and the first
cycle is 2. This causes the xlog_find_zeroed() sanity check to fail
and prevents the filesystem from mounting. This situation has been
reproduced on particular systems via repeated runs of generic/475.

This is an expected state that log recovery already knows how to
deal with, however. Since the log is still partially zeroed, the
head is detected correctly and points to a valid tail. The
subsequent stale block detection clears blocks beyond the head up to
the tail (within a maximum range), with the express purpose of
clearing such out of order writes. As expected, this removes the out
of order cycle 2 blocks at the physical start of the log.

In other words, the only thing that prevents a clean mount and
recovery of the filesystem in this scenario is the specific (last ==
0 && first != 1) sanity check in xlog_find_zeroed(). Since the log
head/tail are now independently validated via cycle, log record and
CRC checks, this highly specific first cycle check is of dubious
value. Remove it and rely on the higher level validation to
determine whether log content is sane and recoverable.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Verify the inode di_forkoff, lifted from xfs_repair's
process_check_inode_forkoff().
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

The iomap direct I/O code issues a single ->end_io call for the whole
I/O request, and if some of the extents cowered needed a COW operation
it will call xfs_reflink_end_cow over the whole range.

When we do AIO writes we drop the iolock after doing the initial setup,
but before the I/O completion.  Between dropping the lock and completing
the I/O we can have a racing buffered write create new delalloc COW fork
extents in the region covered by the outstanding direct I/O write, and
thus see delalloc COW fork extents in xfs_reflink_end_cow.  As
concurrent writes are fundamentally racy and no guarantees are given we
can simply skip those.

This can be easily reproduced with xfstests generic/208 in always_cow
mode.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

xchk_inode_flags2() currently treats any di_flags2 values that the
running kernel doesn't recognize as corruption, and calls
xchk_ino_set_corrupt() if they are set.  However, it's entirely possible
that these flags were set in some newer kernel and are quite valid,
but ignored in this kernel.

(Validators don't care one bit about unknown di_flags2.)

Call xchk_ino_set_warning instead, because this may or may not actually
indicate a problem.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Remove duplicated include xfs_alloc.h
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

This function is only used to punch out delayed allocations on I/O
failure, which means we need to have read the extents earlier.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

When xfs_reflink_allocate_cow() allocates a transaction, it drops
the ILOCK to perform the operation. This Introduces a race condition
where another thread modifying the file can perform the COW
allocation operation underneath us. This result in the retry loop
finding an allocated block and jumping straight to the conversion
code. It does not, however, cancel the transaction it holds and so
this gets leaked. This results in a lockdep warning:

================================================
WARNING: lock held when returning to user space!
4.18.5 #1 Not tainted
------------------------------------------------
worker/6123 is leaving the kernel with locks still held!
1 lock held by worker/6123:
 #0: 000000009eab4f1b (sb_internal#2){.+.+}, at: xfs_trans_alloc+0x17c/0x220

And eventually the filesystem deadlocks because it runs out of log
space that is reserved by the leaked transaction and never gets
released.

The logic flow in xfs_reflink_allocate_cow() is a convoluted mess of
gotos - it's no surprise that it has bug where the flow through
several goto jumps then fails to clean up context from a non-obvious
logic path. CLean up the logic flow and make sure every path does
the right thing.
Reported-by: NAlexander Y. Fomichev <git.user@gmail.com>
Tested-by: NAlexander Y. Fomichev <git.user@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200981Signed-off-by: NDave Chinner <dchinner@redhat.com>
[hch: slight refactor]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

We've had a few reports of lockdep tripping over memory reclaim
context vs filesystem freeze "deadlocks". They all have looked
to be false positives on analysis, but it seems that they are
being tripped because we take freeze references before we run
a GFP_KERNEL allocation for the struct xfs_trans.

We can avoid this false positive vector just by re-ordering the
operations in xfs_trans_alloc(). That is. we need allocate the
structure before we take the freeze reference and enter the GFP_NOFS
allocation context that follows the xfs_trans around. This prevents
lockdep from seeing the GFP_KERNEL allocation inside the transaction
context, and that prevents it from triggering the freeze level vs
alloc context vs reclaim warnings.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>

The xfs_buf_log_item structure has a reference counter with slightly
tricky semantics. In the common case, a buffer is logged and
committed in a transaction, committed to the on-disk log (added to
the AIL) and then finally written back and removed from the AIL. The
bli refcount covers two potentially overlapping timeframes:

 1. the bli is held in an active transaction
 2. the bli is pinned by the log

The caveat to this approach is that the reference counter does not
purely dictate the lifetime of the bli. IOW, when a dirty buffer is
physically logged and unpinned, the bli refcount may go to zero as
the log item is inserted into the AIL. Only once the buffer is
written back can the bli finally be freed.

The above semantics means that it is not enough for the various
refcount decrementing contexts to release the bli on decrement to
zero. xfs_trans_brelse(), transaction commit (->iop_unlock()) and
unpin (->iop_unpin()) must all drop the associated reference and
make additional checks to determine if the current context is
responsible for freeing the item.

For example, if a transaction holds but does not dirty a particular
bli, the commit may drop the refcount to zero. If the bli itself is
clean, it is also not AIL resident and must be freed at this time.
The same is true for xfs_trans_brelse(). If the transaction dirties
a bli and then aborts or an unpin results in an abort due to a log
I/O error, the last reference count holder is expected to explicitly
remove the item from the AIL and release it (since an abort means
filesystem shutdown and metadata writeback will never occur).

This leads to fairly complex checks being replicated in a few
different places. Since ->iop_unlock() and xfs_trans_brelse() are
nearly identical, refactor the logic into a common helper that
implements and documents the semantics in one place. This patch does
not change behavior.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

xfs_trans_brelse() is a bit of a historical mess, similar to
xfs_buf_item_unlock(). It is unnecessarily verbose, has snippets of
commented out code, inconsistency with regard to stale items, etc.

Clean up xfs_trans_brelse() to use similar logic and flow as
xfs_buf_item_unlock() with regard to bli reference count handling.
This patch makes no functional changes, but facilitates further
refactoring of the common bli reference count handling code.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

xfstests generic/388,475 occasionally reproduce assertion failures
in xfs_buf_item_unpin() when the final bli reference is dropped on
an invalidated buffer and the buffer is not locked as it is expected
to be. Invalidated buffers should remain locked on transaction
commit until the final unpin, at which point the buffer is removed
from the AIL and the bli is freed since stale buffers are not
written back.

The assert failures are associated with filesystem shutdown,
typically due to log I/O errors injected by the test. The
problematic situation can occur if the shutdown happens to cause a
race between an active transaction that has invalidated a particular
buffer and an I/O error on a log buffer that contains the bli
associated with the same (now stale) buffer.

Both transaction and log contexts acquire a bli reference. If the
transaction has already invalidated the buffer by the time the I/O
error occurs and ends up aborting due to shutdown, the transaction
and log hold the last two references to a stale bli. If the
transaction cancel occurs first, it treats the buffer as non-stale
due to the aborted state: the bli reference is dropped and the
buffer is released/unlocked. The log buffer I/O error handling
eventually calls into xfs_buf_item_unpin(), drops the final
reference to the bli and treats it as stale. The buffer wasn't left
locked by xfs_buf_item_unlock(), however, so the assert fails and
the buffer is double unlocked. The latter problem is mitigated by
the fact that the fs is shutdown and no further damage is possible.

->iop_unlock() of an invalidated buffer should behave consistently
with respect to the bli refcount, regardless of aborted state. If
the refcount remains elevated on commit, we know the bli is awaiting
an unpin (since it can't be in another transaction) and will be
handled appropriately on log buffer completion. If the final bli
reference of an invalidated buffer is dropped in ->iop_unlock(), we
can assume the transaction has aborted because invalidation implies
a dirty transaction. In the non-abort case, the log would have
acquired a bli reference in ->iop_pin() and prevented bli release at
->iop_unlock() time. In the abort case the item must be freed and
buffer unlocked because it wasn't pinned by the log.

Rework xfs_buf_item_unlock() to simplify the currently circuitous
and duplicate logic and leave invalidated buffers locked based on
bli refcount, regardless of aborted state. This ensures that a
pinned, stale buffer is always found locked when eventually
unpinned.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

Now that deferred operations are completely managed via
transactions, it's no longer necessary to cancel the dfops in error
paths that already cancel the associated transaction. There are a
few such calls lingering throughout the codebase.

Remove all remaining unnecessary calls to xfs_defer_cancel(). This
leaves xfs_defer_cancel() calls in two places. The first is the call
in the transaction cancel path itself, which facilitates this patch.
The second is made via the xfs_defer_finish() error path to provide
consistent error semantics with transaction commit. For example,
xfs_trans_commit() expects an xfs_defer_finish() failure to clean up
the dfops structure before it returns.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

The VFS routine that calls ->get_link blindly copies whatever's returned
into the user's buffer.  If we return a NULL pointer, the vfs will
crash on the null pointer.  Therefore, return -EFSCORRUPTED instead of
blowing up the kernel.

[dgc: clean up with hch's suggestions]

Reported-by: wen.xu@gatech.edu
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NAllison Henderson <allison.henderson@oracle.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

This patch is reworked from an earlier patch that Dan has posted:
https://patchwork.kernel.org/patch/10131727/

VM_MIXEDMAP is used by dax to direct mm paths like vm_normal_page() that
the memory page it is dealing with is not typical memory from the linear
map.  The get_user_pages_fast() path, since it does not resolve the vma,
is already using {pte,pmd}_devmap() as a stand-in for VM_MIXEDMAP, so we
use that as a VM_MIXEDMAP replacement in some locations.  In the cases
where there is no pte to consult we fallback to using vma_is_dax() to
detect the VM_MIXEDMAP special case.

Now that we have explicit driver pfn_t-flag opt-in/opt-out for
get_user_pages() support for DAX we can stop setting VM_MIXEDMAP.  This
also means we no longer need to worry about safely manipulating vm_flags
in a future where we support dynamically changing the dax mode of a
file.

DAX should also now be supported with madvise_behavior(), vma_merge(),
and copy_page_range().

This patch has been tested against ndctl unit test.  It has also been
tested against xfstests commit: 625515d using fake pmem created by
memmap and no additional issues have been observed.

Link: http://lkml.kernel.org/r/152847720311.55924.16999195879201817653.stgit@djiang5-desk3.ch.intel.comSigned-off-by: NDave Jiang <dave.jiang@intel.com>
Acked-by: NDan Williams <dan.j.williams@intel.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Check the values we read in from the AG headers when calculating the
block reservations for a repair transaction.  If they're obviously
wrong, substitute worst case assumptions (rather than ENOSPC on a bogus
reservation request).
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NAllison Henderson <allison.henderson@oracle.com>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>

Since the sb write verifier trips on bad icounts, we should also force a
mount time recalculation of the summary counters if the icount is bad.
This helps us avoid blowing up at freeze/unmount time when the bad
counter gets written back out.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NAllison Henderson <allison.henderson@oracle.com>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>

Fuzzing tool reports a write to null pointer error in the
xfs_bmap_extents_to_btree, fix it by bailing out on encountering
a null pointer.
Signed-off-by: NShan Hai <shan.hai@oracle.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

The old lock tracking infrastructure in xfs using the b_last_holder
field seems to only be useful if you can get into the system with a
debugger; it seems that the existing tracepoints would be the way to
go these days, and this old infrastructure can be removed.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

This patch is the duplicate of ross's fix for ext4 for xfs.

If the refcount of a page is lowered between the time that it is returned
by dax_busy_page() and when the refcount is again checked in
xfs_break_layouts() => ___wait_var_event(), the waiting function
xfs_wait_dax_page() will never be called.  This means that
xfs_break_layouts() will still have 'retry' set to false, so we'll stop
looping and never check the refcount of other pages in this inode.

Instead, always continue looping as long as dax_layout_busy_page() gives us
a page which it found with an elevated refcount.
Signed-off-by: NDave Jiang <dave.jiang@intel.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Rebuild the AGI header items with some help from the rmapbt.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>

Repair the AGFL from the rmap data.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>

Regenerate the AGF from the rmap data.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>