Commit Graph

1461777 Commits

Author SHA1 Message Date
Darrick J. Wong
7cdafd8f10 xfs: hoist per-bucket unlinked list check to helper
In the next patch we're going to make this loop more exciting, so hoist
the code to a helper function to reduce clutter in the resulting code.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-08-03 10:20:42 +02:00
Darrick J. Wong
0c88e10d12 xfs: avoid UAF on sc->tempip in xrep_tempfile_create
LOLLM noticed a potential UAF if the tempfile creation code fails after
it set sc->tempip.  Fix that.

Cc: stable@vger.kernel.org # v6.10
Fixes: 84c14ee39d ("xfs: create temporary files and directories for online repair")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-08-03 10:17:34 +02:00
Darrick J. Wong
b1a296fc22 xfs: nlink scrub must take IOLOCK before determining ILOCK state
In xchk_nlinks_ilock_dir, take the IOLOCK before accessing internal
inode state to figure out if we need to take ILOCK shared or exclusive.
That way we can't race with directory updates.  LOLLM pointed out that
the code was initially correct w.r.t. the IOLOCK, but then I broke it.

Cc: stable@vger.kernel.org # v6.18
Fixes: f477af0cfa ("xfs: fix locking in xchk_nlinks_collect_dir")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-08-03 10:17:34 +02:00
Darrick J. Wong
5ee37132ea xfs: don't zap the attr fork on repair when there are queued pptr updates
LOLLM noticed that xrep_xattr_rebuild_tree doesn't check for queued
parent pointer updates when it decides that it's going to zap the attr
fork.  This is obviously incorrect, so fix that.  We hold the IOLOCK and
the ILOCK of sc->ip at that point in time, so we can't race with any
/new/ operations.

Cc: stable@vger.kernel.org # v6.10
Fixes: e5d7ce0364 ("xfs: replay unlocked parent pointer updates that accrue during xattr repair")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-08-03 10:17:34 +02:00
Darrick J. Wong
8af9cd79cd xfs: don't return EFSCORRUPTED when scrubbing corrupt parent pointers
LOLLM noticed that scrub sets the CORRUPT flag when xfs_parent_from_attr
thinks it's been given a corrupt parent pointer.  This eliminates the
potential to repair the filesystem because that error code is bubbled up
the call stack.  Fix this by collapsing them all to ECANCELED in
xchk_parent_pptr, which doesn't have that trait.

Cc: stable@vger.kernel.org # v6.10
Fixes: 0d29a20fbd ("xfs: scrub parent pointers")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-08-03 10:17:34 +02:00
Darrick J. Wong
5fc643fb86 xfs: don't double-lock when deleting a self-referential directory
LOLLM notices that the dirtree scrubber can detect a directory that
refers to itself.  In this case, it's not correct for the directory tree
repair code to try to iolock/ilock both sc->ip and dp, because they're
the same inode.  Fix this by detecting that corner case and handling it
appropriately.

Cc: stable@vger.kernel.org # v6.10
Fixes: 3f31406aef ("xfs: fix corruptions in the directory tree")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-08-03 10:17:34 +02:00
Darrick J. Wong
97efed1091 xfs: only check mergeability of bnobt records
In the cntbt (free space by block count) btree, records are not supposed
to be in startblock order.  Hence the mergeability check is pointless.
Remove it, since it does nothing, as LOLLM points out.

Cc: stable@vger.kernel.org # v6.4
Fixes: d5784ae827 ("xfs: flag free space btree records that could be merged")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-08-03 10:17:34 +02:00
Andrey Albershteyn
fb082235c6 xfs: fix inverted clearance of inode junk flags
sashiko.dev noticed that these checks clear all the valid flags instead
of invalid. This probably was never hit as it only executed on invalid
flag presence.

Fixes: 2d295fe657 ("xfs: repair inode records")
Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-08-03 10:13:17 +02:00
Lin Jiapeng
b2d5a81dae xfs: fix exchange-range reflink flag clearing issue with INO1_WRITTEN
When exchanging two full-file ranges, xmi_can_exchange_reflink_flags()
can move the reflink inode flag from the file that currently has it to
the other file, as long as exactly one side is marked.  This assumes
that the file contents, and therefore all shared extents, are exchanged.

That assumption is not true when XFS_EXCHMAPS_INO1_WRITTEN is set.
xfs_exchmaps_can_skip_mapping() can skip hole and unwritten mappings
from file1, so an exchange can complete without moving every mapping
that the earlier flag-swap decision accounted for.  In that case the
post-operation cleanup can clear the reflink flag from an inode that
still owns shared written extents.  Later writes then take the
non-reflink write path and may update blocks that should still have
been protected by CoW, which shows up as data corruption between
reflink-related files.

Fix this by disabling the reflink flag exchange whenever
XFS_EXCHMAPS_INO1_WRITTEN is requested.  The contents exchange can still
proceed; the conservative outcome is that both inodes keep the reflink
flag.  The regular reflink flag cleanup path can drop the extra flag
later once the inode no longer has shared extents.

Reported-by: Lin Jiapeng (TencentOS Red Team) <jiapenglin@tencent.com>
Fixes: 966ceafc7a ("xfs: create deferred log items for file mapping exchanges")
Cc: stable@vger.kernel.org # v6.10
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lin Jiapeng <jiapenglin@tencent.com>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-08-03 10:12:48 +02:00
Darrick J. Wong
b28d23c516 xfs: mark nonzero sb_gquotino as corrupt on metadir filesystems
On a metadir filesystem, the superblock gquotino field is always zero
because we find the quota inodes through the metadata directory tree.
A nonzero value is therefore a corruption (as pointed out by LOLLM) so
mark the failure as such.

Cc: stable@vger.kernel.org # v6.13
Fixes: 06b20ef09b ("xfs: check pre-metadir fields correctly")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:25 +02:00
Darrick J. Wong
49933254ba xfs: zero i_nlink before repair puts inode on unlinked list
LOLLM observes that we don't reset i_nlink if we encounter a file with
no parent that isn't on the unlinked list.  This causes unnecessary
assertion trips on debugging kernels and an inconsistent file, so let's
fix that.

Cc: stable@vger.kernel.org # v6.10
Fixes: 669dfe883c ("xfs: update the unlinked list when repairing link counts")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:25 +02:00
Darrick J. Wong
8ed7810472 xfs: rtsummary scrub should treat rtbitmap corruption errors as an xref error
LOLLM notes the discrepancy between the comment saying that this is an
xref error and the code, which marks a (non-xref) corruption error.
This appears to be a regression.

Cc: stable@vger.kernel.org # v6.13
Fixes: e3088ae2dc ("xfs: move RT bitmap and summary information to the rtgroup")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:25 +02:00
Darrick J. Wong
61606f8846 xfs: fix transaction block reservation in xrep_rtbitmap
LOLLM pointed out an inconsistency in the block reservation code in
xrep_rtbitmap.  The first is that the reservation computation is not
consistent between the code that sets up the repair and the code that
tries to avoid exceeding the transaction reservation once we know how
big the rtbitmap really must be.  As a result, the logic doesn't work.

In fixing that, a second problem emerges: if we do readjust, we ask for
the entire reservation all over again.  We really only need the delta,
so ask only for that.

Fix all these problems by hoisting the computation to a trivial helper
so that it gets used in both places.

Cc: stable@vger.kernel.org # v6.14
Fixes: 8defee8dff ("xfs: online repair of realtime bitmaps for a realtime group")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:24 +02:00
Darrick J. Wong
270ffcd9b0 xfs: check cowextsize in xrep_inode_cowextsize
LOLLM points out that the function that corrects cowextsize should check
i_cowextsize, not i_extsize.

Cc: stable@vger.kernel.org # v6.14
Fixes: a9600db96f ("xfs: detect and repair misaligned rtinherit directory cowextsize hints")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:24 +02:00
Christoph Hellwig
7aa67044e7 xfs: update BDI {io,ra}_pages values based on the RT device limits
When using XFS with a main device on an SSD that stores metadata and a RT
device to store data on a HDD, we fail to take the I/O sizes for the RT
device into accounting, leading to up to 5% slower read performance when
using an SSD for metadata vs storing data and metadata on the HDD.

Fix this up by taking the RT settings into account at mount an restoring
the old settings at unmount time, unless the BDI settings have changed
from those set by XFS.

Reported-by: Filip Blagojevic <filip.blagojevic@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:24 +02:00
Yun Zhou
d852729c5f xfs: handle NULL b_addr in xfs_buf_free
When xfs_buf_alloc_backing_mem() fails, xfs_buf_free() is called with
bp->b_addr still NULL.  The code falls through to the folio_put path
which calls virt_to_folio(NULL), dereferencing an invalid address and
causing a kernel crash.

 Call Trace:
  xfs_buf_free+0x25f/0x510
  xfs_buf_alloc+0xc98/0x19b0
  xfs_buf_find_insert+0x55/0x14d0
  xfs_buf_get_map+0x122b/0x17c0
  xfbtree_init_leaf_block+0x11c/0x4a0
  xfbtree_init+0x1bb/0x460
  xrep_rmap_setup_scan+0x100/0x1f0
  xrep_rmapbt+0x41/0xc0

Fix this by skipping folio_put() when bp->b_addr is NULL.

Fixes: 5076a6040c ("xfs: support in-memory buffer cache targets")
Reported-by: syzbot+94c22d92f72f5a235b7d@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=94c22d92f72f5a235b7d
Signed-off-by: Yun Zhou <yun.zhou@windriver.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:24 +02:00
Ibrahim Hashimov
813f8136a2 xfs: bounds-check buffer log item's dirty bitmap
xlog_recover_do_reg_buffer() replays each dirty region described by a
buffer log item's bitmap into the buffer read for that item:

	memcpy(xfs_buf_offset(bp, (uint)bit << XFS_BLF_SHIFT),
		item->ri_buf[i].iov_base,
		nbits << XFS_BLF_SHIFT);

The destination offset (bit/nbits, from the logged dirty bitmap) and the
buffer size (from the logged blf_len) are both attacker-controlled and
otherwise unrelated, yet the only thing bounding the copy is an ASSERT(),
which compiles away on production kernels. A crafted image logging a
small blf_len together with a bitmap bit past the end of that buffer
drives the memcpy() past the buffer's allocation, corrupting adjacent
kernel heap during mount-time log recovery. This is reachable by anyone
who can get a crafted image mounted -- the malicious-filesystem threat
model XFS already guards against elsewhere.

Turn the ASSERT() into a real XFS_IS_CORRUPT() check that aborts recovery
of the buffer with -EFSCORRUPTED, consistent with the validate-and-fail
idiom already used in xlog_recover_do_inode_buffer() and
xfs_dquot_item_recover.c. xlog_recover_do_reg_buffer() therefore becomes
STATIC int and its three callers propagate the error.

Found and confirmed with KASAN on a CONFIG_XFS_DEBUG=n build: the crafted
image trips a slab-out-of-bounds write before this change and fails
recovery cleanly with -EFSCORRUPTED after it.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Ibrahim Hashimov <security@auditcode.ai>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:24 +02:00
Xiang Mei
cc3144da37 xfs: fix off-by-one in rtrefcount btree root level validation
xfs_rtrefcountbt_compute_maxlevels() sets

	mp->m_rtrefc_maxlevels = min(d_maxlevels, r_maxlevels) + 1;

where the trailing "+ 1" already accounts for the inode-root level, so the
deepest valid on-disk root level is m_rtrefc_maxlevels - 1 and a cursor must
satisfy bc_nlevels <= bc_maxlevels (= m_rtrefc_maxlevels).

The two on-disk validation paths, xfs_rtrefcountbt_verify() and
xfs_iformat_rtrefcount(), check the root level with ">" instead of ">=", so a
crafted rtreflink (metadir + realtime + reflink) image whose
/rtgroups/N.refcount inode has bb_level == m_rtrefc_maxlevels is accepted on
mount. xfs_rtrefcountbt_init_cursor() then sets bc_nlevels = bb_level + 1,
exceeding bc_maxlevels by one. Since the xfs_rtrefcountbt_cur slab object is
sized for exactly bc_maxlevels entries, the first btree op on such a cursor
indexes bc_levels[m_rtrefc_maxlevels] past the end of the object. This is
reached by the first rtrefcount cursor built after mount, via log/CoW
recovery (xfs_reflink_recover_cow() during xfs_mountfs()) or an
FS_IOC_GETFSMAP over the realtime device.

Reject a root level equal to m_rtrefc_maxlevels, matching the ">=" form
already used by the sibling data-device refcount/rmap verifiers and the
in-memory rtrmap verifier.

  BUG: KASAN: slab-out-of-bounds in xfs_btree_lookup (fs/xfs/libxfs/xfs_btree.c:2101)
  Write of size 2 at addr ffff888018391658 by task exploit/144
   xfs_btree_lookup (fs/xfs/libxfs/xfs_btree.c:2101)
   xfs_btree_query_range (fs/xfs/libxfs/xfs_btree.c:5308)
   xfs_refcount_recover_cow_leftovers (fs/xfs/libxfs/xfs_refcount.c:2113)
   xfs_reflink_recover_cow (fs/xfs/xfs_reflink.c:1085)
   xlog_recover_finish (fs/xfs/xfs_log_recover.c:3551)
   xfs_mountfs (fs/xfs/xfs_mount.c:1158)
   xfs_fs_fill_super (fs/xfs/xfs_super.c:1940)
   get_tree_bdev_flags (fs/super.c:1634)
   vfs_get_tree (fs/super.c:1694)
   path_mount (fs/namespace.c:4161)
   __x64_sys_mount (fs/namespace.c:4367)
   entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
  The buggy address belongs to the cache xfs_rtrefcountbt_cur of size 216
  The buggy address is located 8 bytes to the right of
   allocated 216-byte region [ffff888018391578, ffff888018391650)
  Kernel panic - not syncing: Fatal exception

Cc: stable@vger.kernel.org # v6.14
Fixes: 9abe03a0e4 ("xfs: introduce realtime refcount btree ondisk definitions")
Reported-by: Weiming Shi <bestswngs@gmail.com>
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:24 +02:00
Qiang Ma
87b2a82e13 xfs: clear zapped attr fork state when bmap repair finds no attr fork
xfstests xfs/377 can make xfs_scrub repeatedly check and repair the
attr block map after inode repair zaps an attr fork.

When inode repair zaps an attr fork, it records
XFS_SICK_INO_BMBTA_ZAPPED so that scrub/repair can revisit the attr fork
block map.  If the fork has been reset to an empty state and removed,
BMBTA repair has no attr fork mappings to rebuild and can return success.

The post-repair scrub then runs with XREP_ALREADY_FIXED set, which means
xchk_file_looks_zapped() deliberately ignores the stale zapped health bit
and asks xchk_bmap() to check the current attr fork.  For an absent attr
fork, xchk_bmap() returns -ENOENT.  Returning that error prevents
xchk_bmap_attr() from marking XFS_SICK_INO_BMBTA_ZAPPED healthy, leaving
the zapped health state behind even though there are no attr fork mappings
left to check.

Treat -ENOENT during post-repair BMBTA revalidation as a clean result for
the zapped attr fork: clear XFS_SICK_INO_BMBTA_ZAPPED and return success.
Keep the existing -ENOENT behavior for ordinary scrubs of absent attr
forks.

Fixes: d9041681dd ("xfs: set inode sick state flags when we zap either ondisk fork")
Cc: stable@vger.kernel.org # v6.8
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Qiang Ma <maqianga@uniontech.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-22 15:06:24 +02:00
Guanghui Yang
b7e53968cb xfs: propagate errors from xfs_rtginode_load
xfs_rtginode_ensure() treats every xfs_rtginode_load() error other than
-ENOENT as success.  This can leave the realtime group inode unset after an
I/O, allocation, or corruption error.  Growfs then continues as though the
inode had been loaded.

Only -ENOENT means that the inode needs to be created.  Return all other
errors to the growfs caller.

Fixes: ae897e0bed ("xfs: support creating per-RTG files in growfs")
Cc: stable@vger.kernel.org
Signed-off-by: Guanghui Yang <3497809730@qq.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-20 11:17:32 +02:00
Darrick J. Wong
59c462b0f5 xfs: don't zap bmbt forks if they are MAXLEVELS tall
LOLLM noticed a discrepancy between the bmbt level checks in the libxfs
bmbt code vs. the inode repair code.  We do actually allow a bmbt root
that proclaims to have a height of XFS_BM_MAXLEVELS.

Cc: stable@vger.kernel.org # v6.8
Fixes: e744cef206 ("xfs: zap broken inode forks")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
15e38a9366 xfs: clamp timestamp nanoseconds correctly
LOLLM noticed an off-by-one error in the nsec clamping; fix that so that
we never have tv_nsec == 1e9.

Cc: stable@vger.kernel.org # v6.8
Fixes: 2d295fe657 ("xfs: repair inode records")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
ba150ce634 xfs: fully check the parent handle when it points to the rootdir
LOLLM noticed that the directory tree path checking declares the path to
be ok if the inumber in the parent pointer reaches the root directory.
Unfortunately, it neglects to check that the generation is correct.  Fix
that by moving the generation check up.

Cc: stable@vger.kernel.org # v6.10
Fixes: 928b721a11 ("xfs: teach online scrub to find directory tree structure problems")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
353a5900bc xfs: handle non-inode owners for rtrmap record checking
LOLLM noticed that two helper functions in the rtrmapbt scrub code don't
actually handle non-inode owners correctly -- CoW staging extents and
rgsuperblock extents are not shareable, but they are mergeable.  Fix
these two helpers.

Cc: stable@vger.kernel.org # v6.14
Fixes: 2d9a3e9805 ("xfs: allow overlapping rtrmapbt records for shared data extents")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
5d72a68f20 xfs: fix off-by-one error when calling xchk_xref_has_rt_owner
LOLLM noticed an off-by-one error when computing the length of the
rtrmap to cross-check.

Cc: stable@vger.kernel.org # v6.14
Fixes: 037a44d827 ("xfs: cross-reference the realtime rmapbt")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
540ddc6262 xfs: set xfarray killable sort correctly
LOLLM noticed that we *disable* interruptible sorts when the KILLABLE
flag is set.  This is backwards.  Fix the incorrect logic, and rename
the variable to make the connection more obvious.

Cc: stable@vger.kernel.org # v6.10
Fixes: 271557de7c ("xfs: reduce the rate of cond_resched calls inside scrub")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
ea6e2d9de2 xfs: grab rtrmap btree when checking rgsuper
LOLLM noticed that we aren't grabbing the rtrmap btree when we check the
realtime group superblock.  As a result, none of the cross-referencing
checks have ever run.  Fix this.

Cc: stable@vger.kernel.org # v6.14
Fixes: 428e488465 ("xfs: allow queued realtime intents to drain before scrubbing")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
9af789fa27 xfs: write the rg superblock when fixing it
The rtgroup superblock fixer should write the rtgroup superblock.
LOLLM noticed this, oops. :/

Cc: stable@vger.kernel.org # v6.13
Fixes: 1433f8f9ce ("xfs: repair realtime group superblock")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
881f2eb0fc xfs: use the rt version of the cow staging checker
LOLLM also noticed that xchk_rtrmapbt_xref ought to be using the rtdev
version of the "is this a cow extent?" helper function, not the datadev
one.

Cc: stable@vger.kernel.org # v6.14
Fixes: 91683bb3f2 ("xfs: cross-reference checks with the rt refcount btree")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
ee248157da xfs: use rtrefcount btree cursor in xchk_xref_is_rt_cow_staging
LOLLM points out that we pass the wrong btree cursor here.  We want the
rtrefcount btree cursor, not the non-rt one.  This is fairly benign
since it only affects tracing data.

Cc: stable@vger.kernel.org # v6.14
Fixes: 91683bb3f2 ("xfs: cross-reference checks with the rt refcount btree")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
d766e4e5e8 xfs: don't wrap around quota ids in dqiterate
LOLLM noticed that q_id is an unsigned 32-bit variable.  If it happens
to be set to XFS_DQ_ID_MAX due to a filesystem that actually has a dquot
for ID_MAX, then this addition will truncate to zero and the iteration
starts over.  Fix this by casting to u64.

Cc: stable@vger.kernel.org # v6.8
Fixes: 21d7500929 ("xfs: improve dquot iteration for scrub")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
60a1dde9d2 xfs: move cow_replace_mapping to xfs_bmap_util.c
Move the actual details of (partially) replacing a COW fork mapping to
xfs_bmap_util.c so that all the code doing hairy operations on subsets
of bmbt_irecs are kept together.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
bcb0621204 xfs: make cow repair somewhat flaky when debugging knob enabled
Introduce a new behavior for the cow fork repair code: if the debugging
knob is enabled, we'll pick a random subrange of each cow fork mapping
to mark as bad.  This will exercise the xrep_cow_replace_mapping more
thoroughly.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
a1caeeadbf xfs: don't replace the wrong part of the cow fork
LOLLM points out that xfs_iext_lookup_extent can return a @got where
got->br_startoff < startoff.  In this case, xrep_cow_replace_range
replaces the entire mapping instead of just the part that had been
marked bad in the bitmap, but advances the bitmap cursor in
xrep_cow_replace by the amount replaced.  As a result, we fail to
replace the end of the bad range, and replace part of the good range.

Fix this by rewriting the replace method to handle replacing the middle
of a cow fork mapping.  This we do by returning both the current mapping
as @got, and the subset of the mapping that we want to replace as @rep,
using @rep to store the results of the new allocation, and comparing
@rep to @got to figure out the exact transformations needed.

Cc: stable@vger.kernel.org # v6.8
Fixes: dbbdbd0086 ("xfs: repair problems in CoW forks")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:01:47 +02:00
Darrick J. Wong
2f4acd0fcd xfs: resample the data fork mapping after cycling ILOCK
xfs_reflink_fill_{cow_hole,delalloc} are both presented with an inode,
a data fork mapping, and a cow fork mapping.  Unfortunately, these two
helpers cycle the ILOCK to grab a transaction, which means that the
mappings are stale as soon as we reacquire the ILOCK.  Currently we
refresh the cow fork mapping by re-calling xfs_find_trim_cow_extent, but
we don't refresh the data fork mapping beforehand, which means that the
xfs_bmap_trim_cow in that function queries the refcount btree about the
wrong physical blocks and returns an inaccurate value in *shared.

If *shared is now false, the directio write proceeds with a stale data
fork mapping.  Fix this by querying the data fork mapping if the
sequence counter changes across the ILOCK cycle.

Cc: hch@lst.de
Cc: stable@vger.kernel.org # v4.11
Fixes: 3c68d44a2b ("xfs: allocate direct I/O COW blocks in iomap_begin")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-14 11:00:14 +02:00
Andrey Albershteyn
9202ee546b xfs: fix null pointer dereference in tracepoint
If dfp is not NULL we exit early here, when dfp is NULL it's allocated
in xfs_defer_alloc() but not assigned. The tracepoint tries to
dereference members of dfp struct.

Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org>
Cc: stable@vger.kernel.org # v6.8
Fixes: 3f3cec0310 ("xfs: force small EFIs for reaping btree extents")
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-12 17:32:27 +02:00
Jinliang Zheng
f88caa121e xfs: use xfs_csn_t for xlog_cil_push_now() push_seq parameter
The push_seq argument to xlog_cil_push_now() carries a CIL checkpoint
sequence number, not a log sequence number (LSN).

Change the parameter type from xfs_lsn_t to xfs_csn_t to correctly
reflect its semantics and match the surrounding types. Both types are
int64_t under the hood, so this is a type-annotation fix with no
behavioural change.

Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-08 14:54:05 +02:00
Cen Zhang
d128ffd2ba xfs: tie zoned sysfs lifetime to zone info
The zoned sysfs directory is currently registered as part of the generic
per-mount sysfs setup, but the data exposed by nr_open_zones has a
narrower lifetime.  mp->m_zone_info is allocated by xfs_mount_zones() and
freed by xfs_unmount_zones(), while the zoned sysfs kobject remained
registered until xfs_mount_sysfs_del().

A read of nr_open_zones can therefore enter through the still-live sysfs
kobject after xfs_unmount_zones() has freed mp->m_zone_info, leading to a
use-after-free in nr_open_zones_show().

Make the zoned sysfs lifetime match the zone-info lifetime inside the zone
allocator.  Create the zoned sysfs directory from xfs_mount_zones() after
the zone allocator has finished setting up, and remove it as the first
step of xfs_unmount_zones(), before any zone allocator teardown can free
m_zone_info.

Sysfs removal deactivates the kernfs nodes and waits for active callbacks
to drain before returning, so this also protects a reader that has already
entered nr_open_zones_show() but has not yet dereferenced m_zone_info.

Validation reproduced this kernel report:
BUG: KASAN: slab-use-after-free in nr_open_zones_show+0x86/0x90
The buggy address belongs to the object at ffff88810b177800 which belongs
to the cache kmalloc-1k of size 1024
The buggy address is located 160 bytes inside of freed 1024-byte region
[ffff88810b177800, ffff88810b177c00)
Read of size 4
Call trace:
  print_report+0xcd/0x620
  nr_open_zones_show+0x86/0x90 (fs/xfs/xfs_sysfs.c:724)
  srso_alias_return_thunk+0x5/0xfbef5
  __virt_addr_valid+0x20c/0x410
  kasan_report+0xdd/0x110
  sysfs_kf_seq_show+0x1bd/0x380
  seq_read_iter+0x40f/0x11b0
  lock_release+0xba/0x260
  mark_held_locks+0x40/0x70
  vfs_read+0x717/0xce0
  __up_read+0x319/0x900
  ksys_read+0xf8/0x1c0
  do_user_addr_fault+0x3d0/0xbc0
  trace_hardirqs_on_prepare+0x23/0xf0
  do_syscall_64+0xc8/0x530 (arch/x86/entry/syscall_64.c:87)
  entry_SYSCALL_64_after_hwframe+0x74/0x7c
Allocated by task stack:
  kasan_save_stack+0x33/0x60
  kasan_save_track+0x14/0x30
  __kasan_kmalloc+0xaa/0xb0
  __kmalloc_cache_noprof+0x205/0x460
  xfs_mount_zones+0x34c/0x2650
  xfs_mountfs+0x1b97/0x1eb0
  xfs_fs_fill_super+0xf2b/0x18a0
  get_tree_bdev_flags+0x310/0x590
  vfs_get_tree+0x8d/0x2e0
  __x64_sys_fsconfig+0x61c/0xbc0
  do_syscall_64+0xc8/0x530 (arch/x86/entry/syscall_64.c:87)
  entry_SYSCALL_64_after_hwframe+0x74/0x7c
Freed by task stack:
  kasan_save_stack+0x33/0x60
  kasan_save_track+0x14/0x30
  kasan_save_free_info+0x3b/0x60
  __kasan_slab_free+0x5f/0x80
  kfree+0x20e/0x4c0
  xfs_unmountfs+0x2fd/0x390
  xfs_fs_put_super+0x60/0x110
  generic_shutdown_super+0x143/0x4b0
  kill_block_super+0x3b/0x90
  xfs_kill_sb+0x12/0x50
  deactivate_locked_super+0xa7/0x160
  cleanup_mnt+0x218/0x420
  task_work_run+0x11a/0x1f0
  exit_to_user_mode_loop+0x13c/0x4f0
  do_syscall_64+0x4a9/0x530 (arch/x86/entry/syscall_64.c:87)
  entry_SYSCALL_64_after_hwframe+0x74/0x7c

Fixes: 62c89988dc ("xfs: expose the number of open zones in sysfs")
Assisted-by: Codex:gpt-5.5
Signed-off-by: Cen Zhang <zzzccc427@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-08 14:54:04 +02:00
Weiming Shi
2094dab19d xfs: fail recovery on a committed log item with no regions
If the first op of a transaction is a bare transaction header
(len == sizeof(struct xfs_trans_header)), xlog_recover_add_to_trans()
adds an item but no region, leaving it on r_itemq with ri_cnt == 0 and
ri_buf == NULL.

The header can be split across op records, so later ops may still add
regions; the item is only invalid if the transaction commits with none.
The runtime commit path never emits such a transaction, so this only
happens on a crafted log.  It came from an AI-assisted code audit of the
recovery parser.

xlog_recover_reorder_trans() calls ITEM_TYPE() on the item, which reads
*(unsigned short *)item->ri_buf[0].iov_base and faults on the NULL
ri_buf.  Reject it there, before the commit handlers that also read
ri_buf[0].

 KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
 RIP: 0010:xlog_recover_reorder_trans (fs/xfs/xfs_log_recover.c:1836)
  xlog_recover_commit_trans (fs/xfs/xfs_log_recover.c:2043)
  xlog_recover_process_data (fs/xfs/xfs_log_recover.c:2501)
  xlog_do_recovery_pass (fs/xfs/xfs_log_recover.c:3244)
  xlog_recover (fs/xfs/xfs_log_recover.c:3493)
  xfs_log_mount (fs/xfs/xfs_log.c:618)
  xfs_mountfs (fs/xfs/xfs_mount.c:1034)
  xfs_fs_fill_super (fs/xfs/xfs_super.c:1938)
  vfs_get_tree (fs/super.c:1695)
  path_mount (fs/namespace.c:4161)
  __x64_sys_mount (fs/namespace.c:4367)

Fixes: 89cebc8477 ("xfs: validate transaction header length on log recovery")
Cc: stable@vger.kernel.org # v4.3
Reported-by: Xiang Mei <xmei5@asu.edu>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-08 14:53:59 +02:00
Weiming Shi
34dd225341 xfs: splice unsorted log items back to the transaction after the loop
On error, xlog_recover_reorder_trans() splices the leftover sort_list
items back to trans->r_itemq inside the loop before breaking out.  The
loop tail already splices the per-fate lists back, so do sort_list there
too, guarded by the assert that used to sit after the loop.

No functional change.  It drops the duplicated splice so the next patch
can add another error case without repeating it.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-07 09:57:19 +02:00
Weiming Shi
5b4396e12c xfs: drop ASSERT(0) on unrecognized log item type
The item type passed to ITEM_TYPE() comes from the on-disk log, so a
fuzzed or crafted image can reach the "unrecognized type" path in
xlog_recover_reorder_trans() and trip its ASSERT(0) on a
CONFIG_XFS_DEBUG kernel.  The -EFSCORRUPTED return handles it fine; drop
the assert.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-07 09:57:19 +02:00
Christoph Hellwig
e4281086ae xfs: simplify __xfs_buf_ioend
__xfs_buf_ioend can only resubmit the buffer for asynchronous
writes, which means the retry handling xfs_buf_iowait is not needed.

Because of this can stop returning a value from __xfs_buf_ioend and
just release the buffer for async I/O that does not require retries.

Also drop the __-prefix now that the semantics are straight forward.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-01 12:29:50 +02:00
Christoph Hellwig
93e21ef2a8 xfs: fix handling of synchronous errors in xfs_buf_submit
Synchronous readers and writers already run __xfs_buf_ioend from
xfs_buf_iowait after being woken through bp->b_iowait, so we
should not call it here, which can lead to double completions.

Fixes: 4b90de5bc0 ("xfs: reduce context switches for synchronous buffered I/O")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-01 12:29:50 +02:00
Christoph Hellwig
b53177d418 xfs: remove xfs_buf_ioend
There are two callers of xfs_buf_ioend, one of which always has the
XBF_ASYNC flag set.  Open code the logic in both callers to prepare for a
bug fix.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-01 12:29:50 +02:00
Christoph Hellwig
4c8b46d832 xfs: improve the xfs_buf_ioend_fail calling convention
Move setting the ASYNC flag into xfs_buf_ioend_fail, assert that the
buffer is locked as expected, and drop the confusing _ioend in the
name.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-01 12:29:50 +02:00
Yousef Alhouseen
cc9af5e461 xfs: use null daddr for unset first bad log block
xlog_do_recovery_pass() may return before setting first_bad.  The caller
must distinguish that case from an error at a valid log block, including
block zero after the log wraps.

Initialize first_bad to XFS_BUF_DADDR_NULL and test it explicitly before
treating the error as a torn write.

Fixes: 7088c4136f ("xfs: detect and trim torn writes during log recovery")
Suggested-by: Darrick J. Wong <djwong@kernel.org>
Reported-by: syzbot+b7dfbed0c6c2b5e9fd34@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b7dfbed0c6c2b5e9fd34
Cc: stable@vger.kernel.org # v4.5
Signed-off-by: Yousef Alhouseen <alhouseenyousef@gmail.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-01 11:39:32 +02:00
Dawei Feng
45de375b25 xfs: fix memory leak in xfs_dqinode_metadir_create()
If xfs_metadir_create() fails in xfs_dqinode_metadir_create(), the current
code returns directly, leaking the allocated update and transaction state.
If the subsequent commit fails, the caller-owned inode reference is left
behind.

Fix this memory leak by routing the create failure path through
xfs_metadir_cancel().  For both create and commit failures, finish and
release any inode returned to the caller, mirroring the unwind pattern in
xfs_metadir_mkdir().

The bug was first flagged by an experimental analysis tool we are
developing for kernel memory-management bugs while analyzing
v6.13-rc1. The tool is still under development and is not yet publicly
available. Manual inspection confirms that the bug is still
present in v7.1.1.

An x86_64 allyesconfig build showed no new warnings. Runtime validation
used kprobe fault injection during `mount -o uquota` on a metadir XFS
image. Injecting xfs_metadir_create() reproduced the old active-update path
that left mount stuck later in mount setup; after this change, the same
injection reported cancel_hits=1 and irele_hits=1. Injecting
xfs_metadir_commit() exercised the old inode-reference leak path; after
this change, it reported irele_hits=1.

Fixes: e80fbe1ad8 ("xfs: use metadir for quota inodes")
Cc: stable@vger.kernel.org # v6.13
Signed-off-by: Dawei Feng <dawei.feng@seu.edu.cn>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-01 11:37:54 +02:00
Yingjie Gao
0c1b3a823a xfs: release dquot buffer after dqflush failure
xfs_qm_dqpurge() gets a locked buffer from xfs_dquot_use_attached_buf().
If xfs_qm_dqflush() fails, the error path skips xfs_buf_relse() and then
calls xfs_dquot_detach_buf(), which tries to lock the same buffer again.

Release the buffer after xfs_qm_dqflush() returns so the error path drops
the caller hold and unlocks the buffer before the dquot is detached,
matching the other dqflush callers.

Fixes: a40fe30868 ("xfs: separate dquot buffer reads from xfs_dqflush")
Cc: stable@vger.kernel.org # v6.13+
Signed-off-by: Yingjie Gao <gaoyingjie@uniontech.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-01 11:35:50 +02:00
Christoph Hellwig
0b434b552e xfs: also mark the buffer stale on verifier failure in xfs_buf_submit
We should treat the buffer that caused a shutdown the same as handling
buffers after a shutdown, so use the same stale && !DONE logic here.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-01 11:25:36 +02:00
Christoph Hellwig
6769087fd8 xfs: open code xfs_buf_ioend_fail in xfs_buf_submit
This better integrates with the other failure handling in xfs_buf_submit,
and prepares for a better API in xfs_buf_ioend_fail.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-07-01 11:21:35 +02:00