commit a4d768e702 upstream.
This structure copy was throwing unaligned access warnings on sparc64:
Kernel unaligned access at TPC[1043c088] xfs_btree_visit_blocks+0x88/0xe0 [xfs]
xfs_btree_copy_ptrs does a memcpy, which avoids it.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3ecb3ac7b9 upstream.
If a malicious user corrupts the refcount btree to cause a cycle between
different levels of the tree, the next mount attempt will deadlock in
the CoW recovery routine while grabbing buffer locks. We can use the
ability to re-grab a buffer that was previous locked to a transaction to
avoid deadlocks, so do that here.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a partial cherry-pick of commit e89c041338
("xfs: implement the GETFSMAP ioctl"), which also adds this helper, and
a great example of why feature patches should be properly split into
their parts.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[hch: split from the larger patch for -stable]
Signed-off-by: Christoph Hellwig <hch@lst.de>
commit 892d2a5f70 upstream.
By run fsstress long enough time enough in RHEL-7, I find an
assertion failure (harder to reproduce on linux-4.11, but problem
is still there):
XFS: Assertion failed: (iflags & BMV_IF_DELALLOC) != 0, file: fs/xfs/xfs_bmap_util.c
The assertion is in xfs_getbmap() funciton:
if (map[i].br_startblock == DELAYSTARTBLOCK &&
--> map[i].br_startoff <= XFS_B_TO_FSB(mp, XFS_ISIZE(ip)))
ASSERT((iflags & BMV_IF_DELALLOC) != 0);
When map[i].br_startoff == XFS_B_TO_FSB(mp, XFS_ISIZE(ip)), the
startoff is just at EOF. But we only need to make sure delalloc
extents that are within EOF, not include EOF.
Signed-off-by: Zorro Lang <zlang@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6eadbf4c8b upstream.
When we're fulfilling a BMAPX request, jump out early if the data fork
is in local format. This prevents us from hitting a debugging check in
bmapi_read and barfing errors back to userspace. The on-disk extent
count check later isn't sufficient for IF_DELALLOC mode because da
extents are in memory and not on disk.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0daaecacb8 upstream.
The delalloc -> real block conversion path uses an incorrect
calculation in the case where the middle part of a delalloc extent
is being converted. This is documented as a rare situation because
XFS generally attempts to maximize contiguity by converting as much
of a delalloc extent as possible.
If this situation does occur, the indlen reservation for the two new
delalloc extents left behind by the conversion of the middle range
is calculated and compared with the original reservation. If more
blocks are required, the delta is allocated from the global block
pool. This delta value can be characterized as the difference
between the new total requirement (temp + temp2) and the currently
available reservation minus those blocks that have already been
allocated (startblockval(PREV.br_startblock) - allocated).
The problem is that the current code does not account for previously
allocated blocks correctly. It subtracts the current allocation
count from the (new - old) delta rather than the old indlen
reservation. This means that more indlen blocks than have been
allocated end up stashed in the remaining extents and free space
accounting is broken as a result.
Fix up the calculation to subtract the allocated block count from
the original extent indlen and thus correctly allocate the
reservation delta based on the difference between the new total
requirement and the unused blocks from the original reservation.
Also remove a bogus assert that contradicts the fact that the new
indlen reservation can be larger than the original indlen
reservation.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fe0be23e68 upstream.
In xfs_reflink_end_cow, we erroneously reserve only enough blocks to
handle adding 1 extent. This is problematic if we fragment free space,
have to do CoW, and then have to perform multiple bmap btree expansions.
Furthermore, the BUI recovery routine doesn't reserve /any/ blocks to
handle btree splits, so log recovery fails after our first error causes
the filesystem to go down.
Therefore, refactor the transaction block reservation macros until we
have a macro that works for our deferred (re)mapping activities, and fix
both problems by using that macro.
With 1k blocks we can hit this fairly often in g/187 if the scratch fs
is big enough.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e20c8a517f upstream.
The quotaoff operation has a race with inode allocation that results
in a livelock. An inode allocation that occurs before the quota
status flags are updated acquires the appropriate dquots for the
inode via xfs_qm_vop_dqalloc(). It then inserts the XFS_INEW inode
into the perag radix tree, sometime later attaches the dquots to the
inode and finally clears the XFS_INEW flag. Quotaoff expects to
release the dquots from all inodes in the filesystem via
xfs_qm_dqrele_all_inodes(). This invokes the AG inode iterator,
which skips inodes in the XFS_INEW state because they are not fully
constructed. If the scan occurs after dquots have been attached to
an inode, but before XFS_INEW is cleared, the newly allocated inode
will continue to hold a reference to the applicable dquots. When
quotaoff invokes xfs_qm_dqpurge_all(), the reference count of those
dquot(s) remain elevated and the dqpurge scan spins indefinitely.
To address this problem, update the xfs_qm_dqrele_all_inodes() scan
to wait on inodes marked on the XFS_INEW state. We wait on the
inodes explicitly rather than skip and retry to avoid continuous
retry loops due to a parallel inode allocation workload. Since
quotaoff updates the quota state flags and uses a synchronous
transaction before the dqrele scan, and dquots are attached to
inodes after radix tree insertion iff quota is enabled, one INEW
waiting pass through the AG guarantees that the scan has processed
all inodes that could possibly hold dquot references.
Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ae2c4ac2dd upstream.
The AG inode iterator currently skips new inodes as such inodes are
inserted into the inode radix tree before they are fully
constructed. Certain contexts require the ability to wait on the
construction of new inodes, however. The fs-wide dquot release from
the quotaoff sequence is an example of this.
Update the AG inode iterator to support the ability to wait on
inodes flagged with XFS_INEW upon request. Create a new
xfs_inode_ag_iterator_flags() interface and support a set of
iteration flags to modify the iteration behavior. When the
XFS_AGITER_INEW_WAIT flag is set, include XFS_INEW flags in the
radix tree inode lookup and wait on them before the callback is
executed.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 756baca27f upstream.
Inodes that are inserted into the perag tree but still under
construction are flagged with the XFS_INEW bit. Most contexts either
skip such inodes when they are encountered or have the ability to
handle them.
The runtime quotaoff sequence introduces a context that must wait
for construction of such inodes to correctly ensure that all dquots
in the fs are released. In anticipation of this, support the ability
to wait on new inodes. Wake the appropriate bit when XFS_INEW is
cleared.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 20e8a06378 upstream.
The quotacheck error handling of the delwri buffer list assumes the
resident buffers are locked and doesn't clear the _XBF_DELWRI_Q flag
on the buffers that are dequeued. This can lead to assert failures
on buffer release and possibly other locking problems.
Move this code to a delwri queue cancel helper function to
encapsulate the logic required to properly release buffers from a
delwri queue. Update the helper to clear the delwri queue flag and
call it from quotacheck.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cb52ee334a upstream.
Directory block readahead uses a complex iteration mechanism to map
between high-level directory blocks and underlying physical extents.
This mechanism attempts to traverse the higher-level dir blocks in a
manner that handles multi-fsb directory blocks and simultaneously
maintains a reference to the corresponding physical blocks.
This logic doesn't handle certain (discontiguous) physical extent
layouts correctly with multi-fsb directory blocks. For example,
consider the case of a 4k FSB filesystem with a 2 FSB (8k) directory
block size and a directory with the following extent layout:
EXT: FILE-OFFSET BLOCK-RANGE AG AG-OFFSET TOTAL
0: [0..7]: 88..95 0 (88..95) 8
1: [8..15]: 80..87 0 (80..87) 8
2: [16..39]: 168..191 0 (168..191) 24
3: [40..63]: 5242952..5242975 1 (72..95) 24
Directory block 0 spans physical extents 0 and 1, dirblk 1 lies
entirely within extent 2 and dirblk 2 spans extents 2 and 3. Because
extent 2 is larger than the directory block size, the readahead code
erroneously assumes the block is contiguous and issues a readahead
based on the physical mapping of the first fsb of the dirblk. This
results in read verifier failure and a spurious corruption or crc
failure, depending on the filesystem format.
Further, the subsequent readahead code responsible for walking
through the physical table doesn't correctly advance the physical
block reference for dirblk 2. Instead of advancing two physical
filesystem blocks, the first iteration of the loop advances 1 block
(correctly), but the subsequent iteration advances 2 more physical
blocks because the next physical extent (extent 3, above) happens to
cover more than dirblk 2. At this point, the higher-level directory
block walking is completely off the rails of the actual physical
layout of the directory for the respective mapping table.
Update the contiguous dirblock logic to consider the current offset
in the physical extent to avoid issuing directory readahead to
unrelated blocks. Also, update the mapping table advancing code to
consider the current offset within the current dirblock to avoid
advancing the mapping reference too far beyond the dirblock.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 023cc840b4 upstream.
Carlos had a case where "find" seemed to start spinning
forever and never return.
This was on a filesystem with non-default multi-fsb (8k)
directory blocks, and a fragmented directory with extents
like this:
0:[0,133646,2,0]
1:[2,195888,1,0]
2:[3,195890,1,0]
3:[4,195892,1,0]
4:[5,195894,1,0]
5:[6,195896,1,0]
6:[7,195898,1,0]
7:[8,195900,1,0]
8:[9,195902,1,0]
9:[10,195908,1,0]
10:[11,195910,1,0]
11:[12,195912,1,0]
12:[13,195914,1,0]
...
i.e. the first extent is a contiguous 2-fsb dir block, but
after that it is fragmented into 1 block extents.
At the top of the readdir path, we allocate a mapping array
which (for this filesystem geometry) can hold 10 extents; see
the assignment to map_info->map_size. During readdir, we are
therefore able to map extents 0 through 9 above into the array
for readahead purposes. If we count by 2, we see that the last
mapped index (9) is the first block of a 2-fsb directory block.
At the end of xfs_dir2_leaf_readbuf() we have 2 loops to fill
more readahead; the outer loop assumes one full dir block is
processed each loop iteration, and an inner loop that ensures
that this is so by advancing to the next extent until a full
directory block is mapped.
The problem is that this inner loop may step past the last
extent in the mapping array as it tries to reach the end of
the directory block. This will read garbage for the extent
length, and as a result the loop control variable 'j' may
become corrupted and never fail the loop conditional.
The number of valid mappings we have in our array is stored
in map->map_valid, so stop this inner loop based on that limit.
There is an ASSERT at the top of the outer loop for this
same condition, but we never made it out of the inner loop,
so the ASSERT never fired.
Huge appreciation for Carlos for debugging and isolating
the problem.
Debugged-and-analyzed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Tested-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3b4683c294 upstream.
Lockdep complains about use of the iolock in inode reclaim context
because it doesn't understand that reclaim has the last reference to
the inode, and thus an iolock->reclaim->iolock deadlock is not
possible.
The iolock is technically not necessary in xfs_inactive() and was
only added to appease an assert in xfs_free_eofblocks(), which can
be called from other non-reclaim contexts. Therefore, just kill the
assert and drop the use of the iolock from reclaim context to quiet
lockdep.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 84358536dc upstream.
Apparently FIEMAP for xattrs has been broken since we switched to
the iomap backend because of an incorrect check for xattr presence.
Also fix the broken locking.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit be6324c00c upstream.
In xfs_ioc_getbmap, we should only copy the fields of struct getbmap
from userspace, or else we end up copying random stack contents into the
kernel. struct getbmap is a strict subset of getbmapx, so a partial
structure copy should work fine.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 696a562072 upstream.
The log covering background task used to be part of the xfssyncd
workqueue. That workqueue was removed as of commit 5889608df ("xfs:
syncd workqueue is no more") and the associated work item scheduled
to the xfs-log wq. The latter is used for log buffer I/O completion.
Since xfs_log_worker() can invoke a log flush, a deadlock is
possible between the xfs-log and xfs-cil workqueues. Consider the
following codepath from xfs_log_worker():
xfs_log_worker()
xfs_log_force()
_xfs_log_force()
xlog_cil_force()
xlog_cil_force_lsn()
xlog_cil_push_now()
flush_work()
The above is in xfs-log wq context and blocked waiting on the
completion of an xfs-cil work item. Concurrently, the cil push in
progress can end up blocked here:
xlog_cil_push_work()
xlog_cil_push()
xlog_write()
xlog_state_get_iclog_space()
xlog_wait(&log->l_flush_wait, ...)
The above is in xfs-cil context waiting on log buffer I/O
completion, which executes in xfs-log wq context. In this scenario
both workqueues are deadlocked waiting on eachother.
Add a new workqueue specifically for the high level log covering and
ail pushing worker, as was the case prior to commit 5889608df.
Diagnosed-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8affebe16d upstream.
xfs_find_get_desired_pgoff() is used to search for offset of hole or
data in page range [index, end] (both inclusive), and the max number
of pages to search should be at least one, if end == index.
Otherwise the only page is missed and no hole or data is found,
which is not correct.
When block size is smaller than page size, this can be demonstrated
by preallocating a file with size smaller than page size and writing
data to the last block. E.g. run this xfs_io command on a 1k block
size XFS on x86_64 host.
# xfs_io -fc "falloc 0 3k" -c "pwrite 2k 1k" \
-c "seek -d 0" /mnt/xfs/testfile
wrote 1024/1024 bytes at offset 2048
1 KiB, 1 ops; 0.0000 sec (33.675 MiB/sec and 34482.7586 ops/sec)
Whence Result
DATA EOF
Data at offset 2k was missed, and lseek(2) returned ENXIO.
This is uncovered by generic/285 subtest 07 and 08 on ppc64 host,
where pagesize is 64k. Because a recent change to generic/285
reduced the preallocated file size to smaller than 64k.
Signed-off-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 63db7c815b upstream.
We've had user reports of unmount hangs in xfs_wait_buftarg() that
analysis shows is due to btp->bt_io_count == -1. bt_io_count
represents the count of in-flight asynchronous buffers and thus
should always be >= 0. xfs_wait_buftarg() waits for this value to
stabilize to zero in order to ensure that all untracked (with
respect to the lru) buffers have completed I/O processing before
unmount proceeds to tear down in-core data structures.
The value of -1 implies an I/O accounting decrement race. Indeed,
the fact that xfs_buf_ioacct_dec() is called from xfs_buf_rele()
(where the buffer lock is no longer held) means that bp->b_flags can
be updated from an unsafe context. While a user-level reproducer is
currently not available, some intrusive hacks to run racing buffer
lookups/ioacct/releases from multiple threads was used to
successfully manufacture this problem.
Existing callers do not expect to acquire the buffer lock from
xfs_buf_rele(). Therefore, we can not safely update ->b_flags from
this context. It turns out that we already have separate buffer
state bits and associated serialization for dealing with buffer LRU
state in the form of ->b_state and ->b_lock. Therefore, replace the
_XBF_IN_FLIGHT flag with a ->b_state variant, update the I/O
accounting wrappers appropriately and make sure they are used with
the correct locking. This ensures that buffer in-flight state can be
modified at buffer release time without racing with modifications
from a buffer lock holder.
Fixes: 9c7504aa72 ("xfs: track and serialize in-flight async buffers against unmount")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Libor Pechacek <lpechacek@suse.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5375023ae1 upstream.
XFS SEEK_HOLE implementation could miss a hole in an unwritten extent as
can be seen by the following command:
xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "pwrite 128k 8k"
-c "seek -h 0" file
wrote 57344/57344 bytes at offset 0
56 KiB, 14 ops; 0.0000 sec (49.312 MiB/sec and 12623.9856 ops/sec)
wrote 8192/8192 bytes at offset 131072
8 KiB, 2 ops; 0.0000 sec (70.383 MiB/sec and 18018.0180 ops/sec)
Whence Result
HOLE 139264
Where we can see that hole at offset 56k was just ignored by SEEK_HOLE
implementation. The bug is in xfs_find_get_desired_pgoff() which does
not properly detect the case when pages are not contiguous.
Fix the problem by properly detecting when found page has larger offset
than expected.
Fixes: d126d43f63
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e2093926a0 upstream.
We currently have two related PMD vs PTE races in the DAX code. These
can both be easily triggered by having two threads reading and writing
simultaneously to the same private mapping, with the key being that
private mapping reads can be handled with PMDs but private mapping
writes are always handled with PTEs so that we can COW.
Here is the first race:
CPU 0 CPU 1
(private mapping write)
__handle_mm_fault()
create_huge_pmd() - FALLBACK
handle_pte_fault()
passes check for pmd_devmap()
(private mapping read)
__handle_mm_fault()
create_huge_pmd()
dax_iomap_pmd_fault() inserts PMD
dax_iomap_pte_fault() does a PTE fault, but we already have a DAX PMD
installed in our page tables at this spot.
Here's the second race:
CPU 0 CPU 1
(private mapping read)
__handle_mm_fault()
passes check for pmd_none()
create_huge_pmd()
dax_iomap_pmd_fault() inserts PMD
(private mapping write)
__handle_mm_fault()
create_huge_pmd() - FALLBACK
(private mapping read)
__handle_mm_fault()
passes check for pmd_none()
create_huge_pmd()
handle_pte_fault()
dax_iomap_pte_fault() inserts PTE
dax_iomap_pmd_fault() inserts PMD,
but we already have a PTE at
this spot.
The core of the issue is that while there is isolation between faults to
the same range in the DAX fault handlers via our DAX entry locking,
there is no isolation between faults in the code in mm/memory.c. This
means for instance that this code in __handle_mm_fault() can run:
if (pmd_none(*vmf.pmd) && transparent_hugepage_enabled(vma)) {
ret = create_huge_pmd(&vmf);
But by the time we actually get to run the fault handler called by
create_huge_pmd(), the PMD is no longer pmd_none() because a racing PTE
fault has installed a normal PMD here as a parent. This is the cause of
the 2nd race. The first race is similar - there is the following check
in handle_pte_fault():
} else {
/* See comment in pte_alloc_one_map() */
if (pmd_devmap(*vmf->pmd) || pmd_trans_unstable(vmf->pmd))
return 0;
So if a pmd_devmap() PMD (a DAX PMD) has been installed at vmf->pmd, we
will bail and retry the fault. This is correct, but there is nothing
preventing the PMD from being installed after this check but before we
actually get to the DAX PTE fault handlers.
In my testing these races result in the following types of errors:
BUG: Bad rss-counter state mm:ffff8800a817d280 idx:1 val:1
BUG: non-zero nr_ptes on freeing mm: 15
Fix this issue by having the DAX fault handlers verify that it is safe
to continue their fault after they have taken an entry lock to block
other racing faults.
[ross.zwisler@linux.intel.com: improve fix for colliding PMD & PTE entries]
Link: http://lkml.kernel.org/r/20170526195932.32178-1-ross.zwisler@linux.intel.com
Link: http://lkml.kernel.org/r/20170522215749.23516-2-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reported-by: Pawel Lebioda <pawel.lebioda@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Pawel Lebioda <pawel.lebioda@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Xiong Zhou <xzhou@redhat.com>
Cc: Eryu Guan <eguan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 239e250e4a upstream.
This fixes a problem with reading files larger than 2GB from a UFS-2
file system:
https://bugzilla.kernel.org/show_bug.cgi?id=195721
The incorrect UFS s_maxsize limit became a problem as of commit
c2a9737f45 ("vfs,mm: fix a dead loop in truncate_inode_pages_range()")
which started using s_maxbytes to avoid a page index overflow in
do_generic_file_read().
That caused files to be truncated on UFS-2 file systems because the
default maximum file size is 2GB (MAX_NON_LFS) and UFS didn't update it.
Here I simply increase the default to a common value used by other file
systems.
Signed-off-by: Richard Narron <comet.berkeley@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Will B <will.brokenbourgh2877@gmail.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b26b78cb72 upstream.
If an NFSv4 client asks us for the supattr_exclcreat, then we must
not return attributes that are unsupported by this minor version.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fixes: 75976de655 ("NFSD: Return word2 bitmask if setting security..,")
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f961e3f2ac upstream.
In error cases, lgp->lg_layout_type may be out of bounds; so we
shouldn't be using it until after the check of nfserr.
This was seen to crash nfsd threads when the server receives a LAYOUTGET
request with a large layout type.
GETDEVICEINFO has the same problem.
Reported-by: Ari Kauppi <Ari.Kauppi@synopsys.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b550a32e60 upstream.
UBSAN: Undefined behaviour in fs/nfsd/nfs4proc.c:1262:34
shift exponent 128 is too large for 32-bit type 'int'
Depending on compiler+architecture, this may cause the check for
layout_type to succeed for overly large values (which seems to be the
case with amd64). The large value will be later used in de-referencing
nfsd4_layout_ops for function pointers.
Reported-by: Jani Tuovila <tuovila@synopsys.com>
Signed-off-by: Ari Kauppi <ari@synopsys.com>
[colin.king@canonical.com: use LAYOUT_TYPE_MAX instead of 32]
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 56e0d71ef1 upstream.
If the server fails to return the attributes as part of an OPEN
reply, and then reboots, we can end up hanging. The reason is that
the client attempts to send a GETATTR in order to pick up the
missing OPEN call, but fails to release the slot first, causing
reboot recovery to deadlock.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fixes: 2e80dbe7ac ("NFSv4.1: Close callback races for OPEN, LAYOUTGET...")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 13e451fdc1 upstream.
Currently DAX read fault can race with write(2) in the following way:
CPU1 - write(2) CPU2 - read fault
dax_iomap_pte_fault()
->iomap_begin() - sees hole
dax_iomap_rw()
iomap_apply()
->iomap_begin - allocates blocks
dax_iomap_actor()
invalidate_inode_pages2_range()
- there's nothing to invalidate
grab_mapping_entry()
- we add zero page in the radix tree
and map it to page tables
The result is that hole page is mapped into page tables (and thus zeros
are seen in mmap) while file has data written in that place.
Fix the problem by locking exception entry before mapping blocks for the
fault. That way we are sure invalidate_inode_pages2_range() call for
racing write will either block on entry lock waiting for the fault to
finish (and unmap stale page tables after that) or read fault will see
already allocated blocks by write(2).
Fixes: 9f141d6ef6
Link: http://lkml.kernel.org/r/20170510085419.27601-5-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d66bb1607e upstream.
proc_create_mount_point() forgot to increase the parent's nlink, and
it resulted in unbalanced hard link numbers, e.g. /proc/fs shows one
less than expected.
Fixes: eb6d38d542 ("proc: Allow creating permanently empty directories...")
Reported-by: Tristan Ye <tristan.ye@suse.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4ff33aafd3 upstream.
When delivering an event to userspace for a file on an NFS share,
if the file is deleted on server side before user reads the event,
user will not get the event.
If the event queue contained several events, the stale event is
quietly dropped and read() returns to user with events read so far
in the buffer.
If the event queue contains a single stale event or if the stale
event is a permission event, read() returns to user with the kernel
internal error code 518 (EOPENSTALE), which is not a POSIX error code.
Check the internal return value -EOPENSTALE in fanotify_read(), just
the same as it is checked in path_openat() and drop the event in the
cases that it is not already dropped.
This is a reproducer from Marko Rauhamaa:
Just take the example program listed under "man fanotify" ("fantest")
and follow these steps:
==============================================================
NFS Server NFS Client(1) NFS Client(2)
==============================================================
# echo foo >/nfsshare/bar.txt
# cat /nfsshare/bar.txt
foo
# ./fantest /nfsshare
Press enter key to terminate.
Listening for events.
# rm -f /nfsshare/bar.txt
# cat /nfsshare/bar.txt
read: Unknown error 518
cat: /nfsshare/bar.txt: Operation not permitted
==============================================================
where NFS Client (1) and (2) are two terminal sessions on a single NFS
Client machine.
Reported-by: Marko Rauhamaa <marko.rauhamaa@f-secure.com>
Tested-by: Marko Rauhamaa <marko.rauhamaa@f-secure.com>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6330d55347 upstream.
When built as a module and running with update_ms >= 0, pstore will Oops
during module unload since the work timer is still running. This makes sure
the worker is stopped before unloading.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e9a330c428 upstream.
The per-prz spinlock should be using the dynamic initializer so that
lockdep can correctly track it. Without this, under lockdep, we get a
warning at boot that the lock is in non-static memory.
Fixes: 109704492e ("pstore: Make spinlock per zone instead of global")
Fixes: 76d5692a58 ("pstore: Correctly initialize spinlock and flags")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6b06cdee81 upstream.
When accessing an encrypted directory without the key, userspace must
operate on filenames derived from the ciphertext names, which contain
arbitrary bytes. Since we must support filenames as long as NAME_MAX,
we can't always just base64-encode the ciphertext, since that may make
it too long. Currently, this is solved by presenting long names in an
abbreviated form containing any needed filesystem-specific hashes (e.g.
to identify a directory block), then the last 16 bytes of ciphertext.
This needs to be sufficient to identify the actual name on lookup.
However, there is a bug. It seems to have been assumed that due to the
use of a CBC (ciphertext block chaining)-based encryption mode, the last
16 bytes (i.e. the AES block size) of ciphertext would depend on the
full plaintext, preventing collisions. However, we actually use CBC
with ciphertext stealing (CTS), which handles the last two blocks
specially, causing them to appear "flipped". Thus, it's actually the
second-to-last block which depends on the full plaintext.
This caused long filenames that differ only near the end of their
plaintexts to, when observed without the key, point to the wrong inode
and be undeletable. For example, with ext4:
# echo pass | e4crypt add_key -p 16 edir/
# seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch
# find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
100000
# sync
# echo 3 > /proc/sys/vm/drop_caches
# keyctl new_session
# find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
2004
# rm -rf edir/
rm: cannot remove 'edir/_A7nNFi3rhkEQlJ6P,hdzluhODKOeWx5V': Structure needs cleaning
...
To fix this, when presenting long encrypted filenames, encode the
second-to-last block of ciphertext rather than the last 16 bytes.
Although it would be nice to solve this without depending on a specific
encryption mode, that would mean doing a cryptographic hash like SHA-256
which would be much less efficient. This way is sufficient for now, and
it's still compatible with encryption modes like HEH which are strong
pseudorandom permutations. Also, changing the presented names is still
allowed at any time because they are only provided to allow applications
to do things like delete encrypted directories. They're not designed to
be used to persistently identify files --- which would be hard to do
anyway, given that they're encrypted after all.
For ease of backports, this patch only makes the minimal fix to both
ext4 and f2fs. It leaves ubifs as-is, since ubifs doesn't compare the
ciphertext block yet. Follow-on patches will clean things up properly
and make the filesystems use a shared helper function.
Fixes: 5de0b4d0cd ("ext4 crypto: simplify and speed up filename encryption")
Reported-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 272f98f684 upstream.
To mitigate some types of offline attacks, filesystem encryption is
designed to enforce that all files in an encrypted directory tree use
the same encryption policy (i.e. the same encryption context excluding
the nonce). However, the fscrypt_has_permitted_context() function which
enforces this relies on comparing struct fscrypt_info's, which are only
available when we have the encryption keys. This can cause two
incorrect behaviors:
1. If we have the parent directory's key but not the child's key, or
vice versa, then fscrypt_has_permitted_context() returned false,
causing applications to see EPERM or ENOKEY. This is incorrect if
the encryption contexts are in fact consistent. Although we'd
normally have either both keys or neither key in that case since the
master_key_descriptors would be the same, this is not guaranteed
because keys can be added or removed from keyrings at any time.
2. If we have neither the parent's key nor the child's key, then
fscrypt_has_permitted_context() returned true, causing applications
to see no error (or else an error for some other reason). This is
incorrect if the encryption contexts are in fact inconsistent, since
in that case we should deny access.
To fix this, retrieve and compare the fscrypt_contexts if we are unable
to set up both fscrypt_infos.
While this slightly hurts performance when accessing an encrypted
directory tree without the key, this isn't a case we really need to be
optimizing for; access *with* the key is much more important.
Furthermore, the performance hit is barely noticeable given that we are
already retrieving the fscrypt_context and doing two keyring searches in
fscrypt_get_encryption_info(). If we ever actually wanted to optimize
this case we might start by caching the fscrypt_contexts.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3adc5fcb7e upstream.
Commit b685d3d65a "block: treat REQ_FUA and REQ_PREFLUSH as
synchronous" removed REQ_SYNC flag from WRITE_{FUA|PREFLUSH|...}
definitions. generic_make_request_checks() however strips REQ_FUA and
REQ_PREFLUSH flags from a bio when the storage doesn't report volatile
write cache and thus write effectively becomes asynchronous which can
lead to performance regressions.
Fix the problem by making sure all bios which are synchronous are
properly marked with REQ_SYNC.
Fixes: b685d3d65a
CC: Jaegeuk Kim <jaegeuk@kernel.org>
CC: linux-f2fs-devel@lists.sourceforge.net
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6332cd32c8 upstream.
If user has no key under an encrypted dir, fscrypt gives digested dentries.
Previously, when looking up a dentry, f2fs only checks its hash value with
first 4 bytes of the digested dentry, which didn't handle hash collisions fully.
This patch enhances to check entire dentry bytes likewise ext4.
Eric reported how to reproduce this issue by:
# seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch
# find edir -type f | xargs stat -c %i | sort | uniq | wc -l
100000
# sync
# echo 3 > /proc/sys/vm/drop_caches
# keyctl new_session
# find edir -type f | xargs stat -c %i | sort | uniq | wc -l
99999
Reported-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
(fixed f2fs_dentry_hash() to work even when the hash is 0)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d3bb910c15 upstream.
Commit 88c5c13a50 (f2fs: fix multiple f2fs_add_link() calls having
same name) does not cover the scenario where inline dentry is enabled.
In that case, F2FS_I(dir)->task will be NULL, and __f2fs_add_link will
lookup dentries one more time.
This patch fixes it by moving the assigment of current task to a upper
level to cover both normal and inline dentry.
Fixes: 88c5c13a50 (f2fs: fix multiple f2fs_add_link() calls having same name)
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c6f82fe90d upstream.
This reverts commit 3436c4bdb3.
This makes a leak to register dirty segments. I reproduced the issue by
modified postmark which injects a lot of file create/delete/update and
finally triggers huge number of SSR allocations.
[Jaegeuk Kim: Change missing incorrect comment]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c541a51b8c upstream.
This patch fixes missing increased max cost caused by a patch that we increased
cose of data segments in greedy algorithm.
Fixes: b9cd20619 "f2fs: node segment is prior to data segment selected victim"
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 876f29460c upstream.
This is based on a patch from Jan Kara that fixed the equivalent race in
the DAX PTE fault path.
Currently DAX PMD read fault can race with write(2) in the following
way:
CPU1 - write(2) CPU2 - read fault
dax_iomap_pmd_fault()
->iomap_begin() - sees hole
dax_iomap_rw()
iomap_apply()
->iomap_begin - allocates blocks
dax_iomap_actor()
invalidate_inode_pages2_range()
- there's nothing to invalidate
grab_mapping_entry()
- we add huge zero page to the radix tree
and map it to page tables
The result is that hole page is mapped into page tables (and thus zeros
are seen in mmap) while file has data written in that place.
Fix the problem by locking exception entry before mapping blocks for the
fault. That way we are sure invalidate_inode_pages2_range() call for
racing write will either block on entry lock waiting for the fault to
finish (and unmap stale page tables after that) or read fault will see
already allocated blocks by write(2).
Fixes: 9f141d6ef6 ("dax: Call ->iomap_begin without entry lock during dax fault")
Link: http://lkml.kernel.org/r/20170510172700.18991-1-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cd656375f9 upstream.
Currently, we didn't invalidate page tables during invalidate_inode_pages2()
for DAX. That could result in e.g. 2MiB zero page being mapped into
page tables while there were already underlying blocks allocated and
thus data seen through mmap were different from data seen by read(2).
The following sequence reproduces the problem:
- open an mmap over a 2MiB hole
- read from a 2MiB hole, faulting in a 2MiB zero page
- write to the hole with write(3p). The write succeeds but we
incorrectly leave the 2MiB zero page mapping intact.
- via the mmap, read the data that was just written. Since the zero
page mapping is still intact we read back zeroes instead of the new
data.
Fix the problem by unconditionally calling invalidate_inode_pages2_range()
in dax_iomap_actor() for new block allocations and by properly
invalidating page tables in invalidate_inode_pages2_range() for DAX
mappings.
Fixes: c6dcf52c23
Link: http://lkml.kernel.org/r/20170510085419.27601-3-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4636e70bb0 upstream.
Patch series "mm,dax: Fix data corruption due to mmap inconsistency",
v4.
This series fixes data corruption that can happen for DAX mounts when
page faults race with write(2) and as a result page tables get out of
sync with block mappings in the filesystem and thus data seen through
mmap is different from data seen through read(2).
The series passes testing with t_mmap_stale test program from Ross and
also other mmap related tests on DAX filesystem.
This patch (of 4):
dax_invalidate_mapping_entry() currently removes DAX exceptional entries
only if they are clean and unlocked. This is done via:
invalidate_mapping_pages()
invalidate_exceptional_entry()
dax_invalidate_mapping_entry()
However, for page cache pages removed in invalidate_mapping_pages()
there is an additional criteria which is that the page must not be
mapped. This is noted in the comments above invalidate_mapping_pages()
and is checked in invalidate_inode_page().
For DAX entries this means that we can can end up in a situation where a
DAX exceptional entry, either a huge zero page or a regular DAX entry,
could end up mapped but without an associated radix tree entry. This is
inconsistent with the rest of the DAX code and with what happens in the
page cache case.
We aren't able to unmap the DAX exceptional entry because according to
its comments invalidate_mapping_pages() isn't allowed to block, and
unmap_mapping_range() takes a write lock on the mapping->i_mmap_rwsem.
Since we essentially never have unmapped DAX entries to evict from the
radix tree, just remove dax_invalidate_mapping_entry().
Fixes: c6dcf52c23 ("mm: Invalidate DAX radix tree entries only if appropriate")
Link: http://lkml.kernel.org/r/20170510085419.27601-2-jack@suse.cz
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4a99f3c83d upstream.
The optimization for opaque dir create was wrongly being applied
also to non-dir create.
Fixes: 97c684cc91 ("ovl: create directories inside merged parent opaque")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
