845 Commits

Author SHA1 Message Date
Matthew Wilcox (Oracle)
4aa554832b ubifs: Set page uptodate in the correct place
[ Upstream commit 723012cab779eee8228376754e22c6594229bf8f ]

Page cache reads are lockless, so setting the freshly allocated page
uptodate before we've overwritten it with the data it's supposed to have
in it will allow a simultaneous reader to see old data.  Move the call
to SetPageUptodate into ubifs_write_end(), which is after we copied the
new data into the page.

Fixes: 1e51764a3c2a ("UBIFS: add new flash file system")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-13 12:50:04 +02:00
Kees Cook
b7e389235c treewide: Remove uninitialized_var() usage
commit 3f649ab728cda8038259d8f14492fe400fbab911 upstream.

Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11 11:45:01 +02:00
Mårten Lindahl
107d481642 ubifs: Free memory for tmpfile name
commit 1fb815b38bb31d6af9bd0540b8652a0d6fe6cfd3 upstream.

When opening a ubifs tmpfile on an encrypted directory, function
fscrypt_setup_filename allocates memory for the name that is to be
stored in the directory entry, but after the name has been copied to the
directory entry inode, the memory is not freed.

When running kmemleak on it we see that it is registered as a leak. The
report below is triggered by a simple program 'tmpfile' just opening a
tmpfile:

  unreferenced object 0xffff88810178f380 (size 32):
    comm "tmpfile", pid 509, jiffies 4294934744 (age 1524.742s)
    backtrace:
      __kmem_cache_alloc_node
      __kmalloc
      fscrypt_setup_filename
      ubifs_tmpfile
      vfs_tmpfile
      path_openat

Free this memory after it has been copied to the inode.

Signed-off-by: Mårten Lindahl <marten.lindahl@axis.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:13:08 +02:00
Zhihao Cheng
cc29c7216d ubifs: Fix memleak when insert_old_idx() failed
commit b5fda08ef213352ac2df7447611eb4d383cce929 upstream.

Following process will cause a memleak for copied up znode:

dirty_cow_znode
  zn = copy_znode(c, znode);
  err = insert_old_idx(c, zbr->lnum, zbr->offs);
  if (unlikely(err))
     return ERR_PTR(err);   // No one refers to zn.

Fetch a reproducer in [Link].

Function copy_znode() is split into 2 parts: resource allocation
and znode replacement, insert_old_idx() is split in similar way,
so resource cleanup could be done in error handling path without
corrupting metadata(mem & disk).
It's okay that old index inserting is put behind of add_idx_dirt(),
old index is used in layout_leb_in_gaps(), so the two processes do
not depend on each other.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216705
Fixes: 1e51764a3c2a ("UBIFS: add new flash file system")
Cc: stable@vger.kernel.org
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:13:07 +02:00
Zhihao Cheng
951ed2e634 Revert "ubifs: dirty_cow_znode: Fix memleak in error handling path"
commit 7d01cb27f6aebc54efbe28d8961a973b8f795b13 upstream.

This reverts commit 122deabfe1428 (ubifs: dirty_cow_znode: Fix memleak
in error handling path).
After commit 122deabfe1428 applied, if insert_old_idx() failed, old
index neither exists in TNC nor in old-index tree. Which means that
old index node could be overwritten in layout_leb_in_gaps(), then
ubifs image will be corrupted in power-cut.

Fixes: 122deabfe1428 (ubifs: dirty_cow_znode: Fix memleak ... path)
Cc: stable@vger.kernel.org
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:13:07 +02:00
Zhihao Cheng
a620ab60d4 ubifs: ubifs_writepage: Mark page dirty after writing inode failed
[ Upstream commit fb8bc4c74ae4526d9489362ab2793a936d072b84 ]

There are two states for ubifs writing pages:
1. Dirty, Private
2. Not Dirty, Not Private

There is a third possibility which maybe related to [1] that page is
private but not dirty caused by following process:

          PA
lock(page)
ubifs_write_end
  attach_page_private		// set Private
    __set_page_dirty_nobuffers	// set Dirty
unlock(page)

write_cache_pages
  lock(page)
  clear_page_dirty_for_io(page)	// clear Dirty
  ubifs_writepage
    write_inode
    // fail, goto out, following codes are not executed
    // do_writepage
    //   set_page_writeback 	// set Writeback
    //   detach_page_private	// clear Private
    //   end_page_writeback 	// clear Writeback
    out:
    unlock(page)		// Private, Not Dirty

                                       PB
				ksys_fadvise64_64
				  generic_fadvise
				     invalidate_inode_page
				     // page is neither Dirty nor Writeback
				       invalidate_complete_page
				       // page_has_private is true
					 try_to_release_page
					   ubifs_releasepage
					     ubifs_assert(c, 0) !!!

Then we may get following assertion failed:
  UBIFS error (ubi0:0 pid 1492): ubifs_assert_failed [ubifs]:
  UBIFS assert failed: 0, in fs/ubifs/file.c:1499
  UBIFS warning (ubi0:0 pid 1492): ubifs_ro_mode [ubifs]:
  switched to read-only mode, error -22
  CPU: 2 PID: 1492 Comm: aa Not tainted 5.16.0-rc2-00012-g7bb767dee0ba-dirty
  Call Trace:
    dump_stack+0x13/0x1b
    ubifs_ro_mode+0x54/0x60 [ubifs]
    ubifs_assert_failed+0x4b/0x80 [ubifs]
    ubifs_releasepage+0x7e/0x1e0 [ubifs]
    try_to_release_page+0x57/0xe0
    invalidate_inode_page+0xfb/0x130
    invalidate_mapping_pagevec+0x12/0x20
    generic_fadvise+0x303/0x3c0
    vfs_fadvise+0x35/0x40
    ksys_fadvise64_64+0x4c/0xb0

Jump [2] to find a reproducer.

[1] https://linux-mtd.infradead.narkive.com/NQoBeT1u/patch-rfc-ubifs-fix-assert-failed-in-ubifs-set-page-dirty
[2] https://bugzilla.kernel.org/show_bug.cgi?id=215357

Fixes: 1e51764a3c2ac0 ("UBIFS: add new flash file system")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:31:57 +01:00
Zhihao Cheng
5759076fc7 ubifs: dirty_cow_znode: Fix memleak in error handling path
[ Upstream commit 122deabfe1428bffe95e2bf364ff8a5059bdf089 ]

Following process will cause a memleak for copied up znode:

dirty_cow_znode
  zn = copy_znode(c, znode);
  err = insert_old_idx(c, zbr->lnum, zbr->offs);
  if (unlikely(err))
     return ERR_PTR(err);   // No one refers to zn.

Fix it by adding copied znode back to tnc, then it will be freed
by ubifs_destroy_tnc_subtree() while closing tnc.

Fetch a reproducer in [Link].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216705
Fixes: 1e51764a3c2a ("UBIFS: add new flash file system")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:31:57 +01:00
Zhihao Cheng
437e010c8b ubifs: Re-statistic cleaned znode count if commit failed
[ Upstream commit 944e096aa24071d3fe22822f6249d3ae309e39ea ]

Dirty znodes will be written on flash in committing process with
following states:

	      process A			|  znode state
------------------------------------------------------
do_commit				| DIRTY_ZNODE
  ubifs_tnc_start_commit		| DIRTY_ZNODE
   get_znodes_to_commit			| DIRTY_ZNODE | COW_ZNODE
    layout_commit			| DIRTY_ZNODE | COW_ZNODE
     fill_gap                           | 0
  write master				| 0 or OBSOLETE_ZNODE

	      process B			|  znode state
------------------------------------------------------
do_commit				| DIRTY_ZNODE[1]
  ubifs_tnc_start_commit		| DIRTY_ZNODE
   get_znodes_to_commit			| DIRTY_ZNODE | COW_ZNODE
  ubifs_tnc_end_commit			| DIRTY_ZNODE | COW_ZNODE
   write_index                          | 0
  write master				| 0 or OBSOLETE_ZNODE[2] or
					| DIRTY_ZNODE[3]

[1] znode is dirtied without concurrent committing process
[2] znode is copied up (re-dirtied by other process) before cleaned
    up in committing process
[3] znode is re-dirtied after cleaned up in committing process

Currently, the clean znode count is updated in free_obsolete_znodes(),
which is called only in normal path. If do_commit failed, clean znode
count won't be updated, which triggers a failure ubifs assertion[4] in
ubifs_tnc_close():
 ubifs_assert_failed [ubifs]: UBIFS assert failed: freed == n

[4] Commit 380347e9ca7682 ("UBIFS: Add an assertion for clean_zn_cnt").

Fix it by re-statisticing cleaned znode count in tnc_destroy_cnext().

Fetch a reproducer in [Link].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216704
Fixes: 1e51764a3c2a ("UBIFS: add new flash file system")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:31:57 +01:00
Zhihao Cheng
a0e39670fd ubifs: Reserve one leb for each journal head while doing budget
[ Upstream commit e874dcde1cbf82c786c0e7f2899811c02630cc52 ]

UBIFS calculates available space by c->main_bytes - c->lst.total_used
(which means non-index lebs' free and dirty space is accounted into
total available), then index lebs and four lebs (one for gc_lnum, one
for deletions, two for journal heads) are deducted.
In following situation, ubifs may get -ENOSPC from make_reservation():
 LEB 84: DATAHD   free 122880 used 1920  dirty 2176  dark 6144
 LEB 110:DELETION free 126976 used 0     dirty 0     dark 6144 (empty)
 LEB 201:gc_lnum  free 126976 used 0     dirty 0     dark 6144
 LEB 272:GCHD     free 77824  used 47672 dirty 1480  dark 6144
 LEB 356:BASEHD   free 0      used 39776 dirty 87200 dark 6144
 OTHERS: index lebs, zero-available non-index lebs

UBIFS calculates the available bytes is 6888 (How to calculate it:
126976 * 5[remain main bytes] - 1920[used] - 47672[used] - 39776[used] -
126976 * 1[deletions] - 126976 * 1[gc_lnum] - 126976 * 2[journal heads]
- 6144 * 5[dark] = 6888) after doing budget, however UBIFS cannot use
BASEHD's dirty space(87200), because UBIFS cannot find next BASEHD to
reclaim current BASEHD. (c->bi.min_idx_lebs equals to c->lst.idx_lebs,
the empty leb won't be found by ubifs_find_free_space(), and dirty index
lebs won't be picked as gced lebs. All non-index lebs has dirty space
less then c->dead_wm, non-index lebs won't be picked as gced lebs
either. So new free lebs won't be produced.). See more details in Link.

To fix it, reserve one leb for each journal head while doing budget.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216562
Fixes: 1e51764a3c2ac0 ("UBIFS: add new flash file system")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:31:56 +01:00
Zhihao Cheng
6cc10bbc89 ubifs: do_rename: Fix wrong space budget when target inode's nlink > 1
[ Upstream commit 25fce616a61fc2f1821e4a9ce212d0e064707093 ]

If target inode is a special file (eg. block/char device) with nlink
count greater than 1, the inode with ui->data will be re-written on
disk. However, UBIFS losts target inode's data_len while doing space
budget. Bad space budget may let make_reservation() return with -ENOSPC,
which could turn ubifs to read-only mode in do_writepage() process.

Fetch a reproducer in [Link].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216494
Fixes: 1e51764a3c2ac0 ("UBIFS: add new flash file system")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:31:56 +01:00
Zhihao Cheng
2d115ac3bb ubifs: Fix wrong dirty space budget for dirty inode
[ Upstream commit b248eaf049d9cdc5eb76b59399e4d3de233f02ac ]

Each dirty inode should reserve 'c->bi.inode_budget' bytes in space
budget calculation. Currently, space budget for dirty inode reports
more space than what UBIFS actually needs to write.

Fixes: 1e51764a3c2ac0 ("UBIFS: add new flash file system")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:31:56 +01:00
Zhihao Cheng
664d85a509 ubifs: Rectify space budget for ubifs_xrename()
[ Upstream commit 1b2ba09060e41adb356b9ae58ef94a7390928004 ]

There is no space budget for ubifs_xrename(). It may let
make_reservation() return with -ENOSPC, which could turn
ubifs to read-only mode in do_writepage() process.
Fix it by adding space budget for ubifs_xrename().

Fetch a reproducer in [Link].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216569
Fixes: 9ec64962afb170 ("ubifs: Implement RENAME_EXCHANGE")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:31:56 +01:00
Zhihao Cheng
2081d0c3ef ubifs: Rectify space budget for ubifs_symlink() if symlink is encrypted
[ Upstream commit c2c36cc6ca23e614f9e4238d0ecf48549ee9002a ]

Fix bad space budget when symlink file is encrypted. Bad space budget
may let make_reservation() return with -ENOSPC, which could turn ubifs
to read-only mode in do_writepage() process.

Fetch a reproducer in [Link].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216490
Fixes: ca7f85be8d6cf9 ("ubifs: Add support for encrypted symlinks")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:31:56 +01:00
Zhihao Cheng
b7a0f0f2dc ubifs: Rectify space amount budget for mkdir/tmpfile operations
[ Upstream commit a6dab6607d4681d227905d5198710b575dbdb519 ]

UBIFS should make sure the flash has enough space to store dirty (Data
that is newer than disk) data (in memory), space budget is exactly
designed to do that. If space budget calculates less data than we need,
'make_reservation()' will do more work(return -ENOSPC if no free space
lelf, sometimes we can see "cannot reserve xxx bytes in jhead xxx, error
-28" in ubifs error messages) with ubifs inodes locked, which may effect
other syscalls.

A simple way to decide how much space do we need when make a budget:
See how much space is needed by 'make_reservation()' in ubifs_jnl_xxx()
function according to corresponding operation.

It's better to report ENOSPC in ubifs_budget_space(), as early as we can.

Fixes: 474b93704f32163 ("ubifs: Implement O_TMPFILE")
Fixes: 1e51764a3c2ac05 ("UBIFS: add new flash file system")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-15 14:15:00 +02:00
Baokun Li
a2d0d4b6d1 ubifs: rename_whiteout: correct old_dir size computing
commit 705757274599e2e064dd3054aabc74e8af31a095 upstream.

When renaming the whiteout file, the old whiteout file is not deleted.
Therefore, we add the old dentry size to the old dir like XFS.
Otherwise, an error may be reported due to `fscki->calc_sz != fscki->size`
in check_indes.

Fixes: 9e0a1fff8db56ea ("ubifs: Implement RENAME_WHITEOUT")
Reported-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 14:14:58 +02:00
Zhihao Cheng
5343575aa1 ubifs: Fix read out-of-bounds in ubifs_wbuf_write_nolock()
commit 4f2262a334641e05f645364d5ade1f565c85f20b upstream.

Function ubifs_wbuf_write_nolock() may access buf out of bounds in
following process:

ubifs_wbuf_write_nolock():
  aligned_len = ALIGN(len, 8);   // Assume len = 4089, aligned_len = 4096
  if (aligned_len <= wbuf->avail) ... // Not satisfy
  if (wbuf->used) {
    ubifs_leb_write()  // Fill some data in avail wbuf
    len -= wbuf->avail;   // len is still not 8-bytes aligned
    aligned_len -= wbuf->avail;
  }
  n = aligned_len >> c->max_write_shift;
  if (n) {
    n <<= c->max_write_shift;
    err = ubifs_leb_write(c, wbuf->lnum, buf + written,
                          wbuf->offs, n);
    // n > len, read out of bounds less than 8(n-len) bytes
  }

, which can be catched by KASAN:
  =========================================================
  BUG: KASAN: slab-out-of-bounds in ecc_sw_hamming_calculate+0x1dc/0x7d0
  Read of size 4 at addr ffff888105594ff8 by task kworker/u8:4/128
  Workqueue: writeback wb_workfn (flush-ubifs_0_0)
  Call Trace:
    kasan_report.cold+0x81/0x165
    nand_write_page_swecc+0xa9/0x160
    ubifs_leb_write+0xf2/0x1b0 [ubifs]
    ubifs_wbuf_write_nolock+0x421/0x12c0 [ubifs]
    write_head+0xdc/0x1c0 [ubifs]
    ubifs_jnl_write_inode+0x627/0x960 [ubifs]
    wb_workfn+0x8af/0xb80

Function ubifs_wbuf_write_nolock() accepts that parameter 'len' is not 8
bytes aligned, the 'len' represents the true length of buf (which is
allocated in 'ubifs_jnl_xxx', eg. ubifs_jnl_write_inode), so
ubifs_wbuf_write_nolock() must handle the length read from 'buf' carefully
to write leb safely.

Fetch a reproducer in [Link].

Fixes: 1e51764a3c2ac0 ("UBIFS: add new flash file system")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214785
Reported-by: Chengsong Ke <kechengsong@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 14:14:58 +02:00
Zhihao Cheng
b98a46d053 ubifs: setflags: Make dirtied_ino_d 8 bytes aligned
commit 1b83ec057db16b4d0697dc21ef7a9743b6041f72 upstream.

Make 'ui->data_len' aligned with 8 bytes before it is assigned to
dirtied_ino_d. Since 8871d84c8f8b0c6b("ubifs: convert to fileattr")
applied, 'setflags()' only affects regular files and directories, only
xattr inode, symlink inode and special inode(pipe/char_dev/block_dev)
have none- zero 'ui->data_len' field, so assertion
'!(req->dirtied_ino_d & 7)' cannot fail in ubifs_budget_space().
To avoid assertion fails in future evolution(eg. setflags can operate
special inodes), it's better to make dirtied_ino_d 8 bytes aligned,
after all aligned size is still zero for regular files.

Fixes: 1e51764a3c2ac05a ("UBIFS: add new flash file system")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 14:14:58 +02:00
Zhihao Cheng
07ef99621e ubifs: Add missing iput if do_tmpfile() failed in rename whiteout
commit 716b4573026bcbfa7b58ed19fe15554bac66b082 upstream.

whiteout inode should be put when do_tmpfile() failed if inode has been
initialized. Otherwise we will get following warning during umount:
  UBIFS error (ubi0:0 pid 1494): ubifs_assert_failed [ubifs]: UBIFS
  assert failed: c->bi.dd_growth == 0, in fs/ubifs/super.c:1930
  VFS: Busy inodes after unmount of ubifs. Self-destruct in 5 seconds.

Fixes: 9e0a1fff8db56ea ("ubifs: Implement RENAME_WHITEOUT")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Suggested-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 14:14:58 +02:00
Zhihao Cheng
9dddc82114 ubifs: Fix deadlock in concurrent rename whiteout and inode writeback
commit afd427048047e8efdedab30e8888044e2be5aa9c upstream.

Following hung tasks:
[   77.028764] task:kworker/u8:4    state:D stack:    0 pid:  132
[   77.028820] Call Trace:
[   77.029027]  schedule+0x8c/0x1b0
[   77.029067]  mutex_lock+0x50/0x60
[   77.029074]  ubifs_write_inode+0x68/0x1f0 [ubifs]
[   77.029117]  __writeback_single_inode+0x43c/0x570
[   77.029128]  writeback_sb_inodes+0x259/0x740
[   77.029148]  wb_writeback+0x107/0x4d0
[   77.029163]  wb_workfn+0x162/0x7b0

[   92.390442] task:aa              state:D stack:    0 pid: 1506
[   92.390448] Call Trace:
[   92.390458]  schedule+0x8c/0x1b0
[   92.390461]  wb_wait_for_completion+0x82/0xd0
[   92.390469]  __writeback_inodes_sb_nr+0xb2/0x110
[   92.390472]  writeback_inodes_sb_nr+0x14/0x20
[   92.390476]  ubifs_budget_space+0x705/0xdd0 [ubifs]
[   92.390503]  do_rename.cold+0x7f/0x187 [ubifs]
[   92.390549]  ubifs_rename+0x8b/0x180 [ubifs]
[   92.390571]  vfs_rename+0xdb2/0x1170
[   92.390580]  do_renameat2+0x554/0x770

, are caused by concurrent rename whiteout and inode writeback processes:
	rename_whiteout(Thread 1)	        wb_workfn(Thread2)
ubifs_rename
  do_rename
    lock_4_inodes (Hold ui_mutex)
    ubifs_budget_space
      make_free_space
        shrink_liability
	  __writeback_inodes_sb_nr
	    bdi_split_work_to_wbs (Queue new wb work)
					      wb_do_writeback(wb work)
						__writeback_single_inode
					          ubifs_write_inode
					            LOCK(ui_mutex)
							   ↑
	      wb_wait_for_completion (Wait wb work) <-- deadlock!

Reproducer (Detail program in [Link]):
  1. SYS_renameat2("/mp/dir/file", "/mp/dir/whiteout", RENAME_WHITEOUT)
  2. Consume out of space before kernel(mdelay) doing budget for whiteout

Fix it by doing whiteout space budget before locking ubifs inodes.
BTW, it also fixes wrong goto tag 'out_release' in whiteout budget
error handling path(It should at least recover dir i_size and unlock
4 ubifs inodes).

Fixes: 9e0a1fff8db56ea ("ubifs: Implement RENAME_WHITEOUT")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214733
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 14:14:58 +02:00
Zhihao Cheng
2b3236ecf9 ubifs: rename_whiteout: Fix double free for whiteout_ui->data
commit 40a8f0d5e7b3999f096570edab71c345da812e3e upstream.

'whiteout_ui->data' will be freed twice if space budget fail for
rename whiteout operation as following process:

rename_whiteout
  dev = kmalloc
  whiteout_ui->data = dev
  kfree(whiteout_ui->data)  // Free first time
  iput(whiteout)
    ubifs_free_inode
      kfree(ui->data)	    // Double free!

KASAN reports:
==================================================================
BUG: KASAN: double-free or invalid-free in ubifs_free_inode+0x4f/0x70
Call Trace:
  kfree+0x117/0x490
  ubifs_free_inode+0x4f/0x70 [ubifs]
  i_callback+0x30/0x60
  rcu_do_batch+0x366/0xac0
  __do_softirq+0x133/0x57f

Allocated by task 1506:
  kmem_cache_alloc_trace+0x3c2/0x7a0
  do_rename+0x9b7/0x1150 [ubifs]
  ubifs_rename+0x106/0x1f0 [ubifs]
  do_syscall_64+0x35/0x80

Freed by task 1506:
  kfree+0x117/0x490
  do_rename.cold+0x53/0x8a [ubifs]
  ubifs_rename+0x106/0x1f0 [ubifs]
  do_syscall_64+0x35/0x80

The buggy address belongs to the object at ffff88810238bed8 which
belongs to the cache kmalloc-8 of size 8
==================================================================

Let ubifs_free_inode() free 'whiteout_ui->data'. BTW, delete unused
assignment 'whiteout_ui->data_len = 0', process 'ubifs_evict_inode()
-> ubifs_jnl_delete_inode() -> ubifs_jnl_write_inode()' doesn't need it
(because 'inc_nlink(whiteout)' won't be excuted by 'goto out_release',
 and the nlink of whiteout inode is 0).

Fixes: 9e0a1fff8db56ea ("ubifs: Implement RENAME_WHITEOUT")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 14:14:58 +02:00
Petr Cvachoucek
191cf58d06 ubifs: Error path in ubifs_remount_rw() seems to wrongly free write buffers
commit 3fea4d9d160186617ff40490ae01f4f4f36b28ff upstream.

it seems freeing the write buffers in the error path of the
ubifs_remount_rw() is wrong. It leads later to a kernel oops like this:

[10016.431274] UBIFS (ubi0:0): start fixing up free space
[10090.810042] UBIFS (ubi0:0): free space fixup complete
[10090.814623] UBIFS error (ubi0:0 pid 512): ubifs_remount_fs: cannot
spawn "ubifs_bgt0_0", error -4
[10101.915108] UBIFS (ubi0:0): background thread "ubifs_bgt0_0" started,
PID 517
[10105.275498] Unable to handle kernel NULL pointer dereference at
virtual address 0000000000000030
[10105.284352] Mem abort info:
[10105.287160]   ESR = 0x96000006
[10105.290252]   EC = 0x25: DABT (current EL), IL = 32 bits
[10105.295592]   SET = 0, FnV = 0
[10105.298652]   EA = 0, S1PTW = 0
[10105.301848] Data abort info:
[10105.304723]   ISV = 0, ISS = 0x00000006
[10105.308573]   CM = 0, WnR = 0
[10105.311564] user pgtable: 4k pages, 48-bit VAs, pgdp=00000000f03d1000
[10105.318034] [0000000000000030] pgd=00000000f6cee003,
pud=00000000f4884003, pmd=0000000000000000
[10105.326783] Internal error: Oops: 96000006 [#1] PREEMPT SMP
[10105.332355] Modules linked in: ath10k_pci ath10k_core ath mac80211
libarc4 cfg80211 nvme nvme_core cryptodev(O)
[10105.342468] CPU: 3 PID: 518 Comm: touch Tainted: G           O
5.4.3 #1
[10105.349517] Hardware name: HYPEX CPU (DT)
[10105.353525] pstate: 40000005 (nZcv daif -PAN -UAO)
[10105.358324] pc : atomic64_try_cmpxchg_acquire.constprop.22+0x8/0x34
[10105.364596] lr : mutex_lock+0x1c/0x34
[10105.368253] sp : ffff000075633aa0
[10105.371563] x29: ffff000075633aa0 x28: 0000000000000001
[10105.376874] x27: ffff000076fa80c8 x26: 0000000000000004
[10105.382185] x25: 0000000000000030 x24: 0000000000000000
[10105.387495] x23: 0000000000000000 x22: 0000000000000038
[10105.392807] x21: 000000000000000c x20: ffff000076fa80c8
[10105.398119] x19: ffff000076fa8000 x18: 0000000000000000
[10105.403429] x17: 0000000000000000 x16: 0000000000000000
[10105.408741] x15: 0000000000000000 x14: fefefefefefefeff
[10105.414052] x13: 0000000000000000 x12: 0000000000000fe0
[10105.419364] x11: 0000000000000fe0 x10: ffff000076709020
[10105.424675] x9 : 0000000000000000 x8 : 00000000000000a0
[10105.429986] x7 : ffff000076fa80f4 x6 : 0000000000000030
[10105.435297] x5 : 0000000000000000 x4 : 0000000000000000
[10105.440609] x3 : 0000000000000000 x2 : ffff00006f276040
[10105.445920] x1 : ffff000075633ab8 x0 : 0000000000000030
[10105.451232] Call trace:
[10105.453676]  atomic64_try_cmpxchg_acquire.constprop.22+0x8/0x34
[10105.459600]  ubifs_garbage_collect+0xb4/0x334
[10105.463956]  ubifs_budget_space+0x398/0x458
[10105.468139]  ubifs_create+0x50/0x180
[10105.471712]  path_openat+0x6a0/0x9b0
[10105.475284]  do_filp_open+0x34/0x7c
[10105.478771]  do_sys_open+0x78/0xe4
[10105.482170]  __arm64_sys_openat+0x1c/0x24
[10105.486180]  el0_svc_handler+0x84/0xc8
[10105.489928]  el0_svc+0x8/0xc
[10105.492808] Code: 52800013 17fffffb d2800003 f9800011 (c85ffc05)
[10105.498903] ---[ end trace 46b721d93267a586 ]---

To reproduce the problem:

1. Filesystem initially mounted read-only, free space fixup flag set.

2. mount -o remount,rw <mountpoint>

3. it takes some time (free space fixup running)
    ... try to terminate running mount by CTRL-C
    ... does not respond, only after free space fixup is complete
    ... then "ubifs_remount_fs: cannot spawn "ubifs_bgt0_0", error -4"

4. mount -o remount,rw <mountpoint>
    ... now finished instantly (fixup already done).

5. Create file or just unmount the filesystem and we get the oops.

Cc: <stable@vger.kernel.org>
Fixes: b50b9f408502 ("UBIFS: do not free write-buffers when in R/O mode")
Signed-off-by: Petr Cvachoucek <cvachoucek@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27 09:04:30 +01:00
Eric Biggers
7e7b9f8867 ubifs: report correct st_size for encrypted symlinks
commit 064c734986011390b4d111f1a99372b7f26c3850 upstream.

The stat() family of syscalls report the wrong size for encrypted
symlinks, which has caused breakage in several userspace programs.

Fix this by calling fscrypt_symlink_getattr() after ubifs_getattr() for
encrypted symlinks.  This function computes the correct size by reading
and decrypting the symlink target (if it's not already cached).

For more details, see the commit which added fscrypt_symlink_getattr().

Fixes: ca7f85be8d6c ("ubifs: Add support for encrypted symlinks")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210702065350.209646-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-22 11:47:56 +02:00
Zhihao Cheng
e6afff12ac ubifs: Set/Clear I_LINKABLE under i_lock for whiteout inode
[ Upstream commit a801fcfeef96702fa3f9b22ad56c5eb1989d9221 ]

xfstests-generic/476 reports a warning message as below:

WARNING: CPU: 2 PID: 30347 at fs/inode.c:361 inc_nlink+0x52/0x70
Call Trace:
  do_rename+0x502/0xd40 [ubifs]
  ubifs_rename+0x8b/0x180 [ubifs]
  vfs_rename+0x476/0x1080
  do_renameat2+0x67c/0x7b0
  __x64_sys_renameat2+0x6e/0x90
  do_syscall_64+0x66/0xe0
  entry_SYSCALL_64_after_hwframe+0x44/0xae

Following race case can cause this:
         rename_whiteout(Thread 1)             wb_workfn(Thread 2)
ubifs_rename
  do_rename
                                          __writeback_single_inode
					    spin_lock(&inode->i_lock)
    whiteout->i_state |= I_LINKABLE
                                            inode->i_state &= ~dirty;
---- How race happens on i_state:
    (tmp = whiteout->i_state | I_LINKABLE)
		                           (tmp = inode->i_state & ~dirty)
    (whiteout->i_state = tmp)
		                           (inode->i_state = tmp)
----
					    spin_unlock(&inode->i_lock)
    inc_nlink(whiteout)
    WARN_ON(!(inode->i_state & I_LINKABLE)) !!!

Fix to add i_lock to avoid i_state update race condition.

Fixes: 9e0a1fff8db56ea ("ubifs: Implement RENAME_WHITEOUT")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:16:13 +02:00
Guochun Mao
c160368f28 ubifs: Only check replay with inode type to judge if inode linked
commit 3e903315790baf4a966436e7f32e9c97864570ac upstream.

Conside the following case, it just write a big file into flash,
when complete writing, delete the file, and then power off promptly.
Next time power on, we'll get a replay list like:
...
LEB 1105:211344 len 4144 deletion 0 sqnum 428783 key type 1 inode 80
LEB 15:233544 len 160 deletion 1 sqnum 428785 key type 0 inode 80
LEB 1105:215488 len 4144 deletion 0 sqnum 428787 key type 1 inode 80
...
In the replay list, data nodes' deletion are 0, and the inode node's
deletion is 1. In current logic, the file's dentry will be removed,
but inode and the flash space it occupied will be reserved.
User will see that much free space been disappeared.

We only need to check the deletion value of the following inode type
node of the replay entry.

Fixes: e58725d51fa8 ("ubifs: Handle re-linking of inodes correctly while recovery")
Cc: stable@vger.kernel.org
Signed-off-by: Guochun Mao <guochun.mao@mediatek.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-22 10:59:19 +02:00
Eric Biggers
5664f1cb08 ubifs: prevent creating duplicate encrypted filenames
commit 76786a0f083473de31678bdb259a3d4167cf756d upstream.

As described in "fscrypt: add fscrypt_is_nokey_name()", it's possible to
create a duplicate filename in an encrypted directory by creating a file
concurrently with adding the directory's encryption key.

Fix this bug on ubifs by rejecting no-key dentries in ubifs_create(),
ubifs_mkdir(), ubifs_mknod(), and ubifs_symlink().

Note that ubifs doesn't actually report the duplicate filenames from
readdir, but rather it seems to replace the original dentry with a new
one (which is still wrong, just a different effect from ext4).

On ubifs, this fixes xfstest generic/595 as well as the new xfstest I
wrote specifically for this bug.

Fixes: f4f61d2cc6d8 ("ubifs: Implement encrypted filenames")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201118075609.120337-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-06 14:44:59 +01:00
Richard Weinberger
1343995da9 ubifs: wbuf: Don't leak kernel memory to flash
commit 20f1431160c6b590cdc269a846fc5a448abf5b98 upstream.

Write buffers use a kmalloc()'ed buffer, they can leak
up to seven bytes of kernel memory to flash if writes are not
aligned.
So use ubifs_pad() to fill these gaps with padding bytes.
This was never a problem while scanning because the scanner logic
manually aligns node lengths and skips over these gaps.

Cc: <stable@vger.kernel.org>
Fixes: 1e51764a3c2ac05a2 ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:26:13 +01:00
Zhihao Cheng
b08433b1c5 ubifs: dent: Fix some potential memory leaks while iterating entries
commit 58f6e78a65f1fcbf732f60a7478ccc99873ff3ba upstream.

Fix some potential memory leaks in error handling branches while
iterating dent entries. For example, function dbg_check_dir()
forgets to free pdent if it exists.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>
Fixes: 1e51764a3c2ac05a2 ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05 11:08:52 +01:00
Eric Biggers
b699b0067c fscrypt: fix race where ->lookup() marks plaintext dentry as ciphertext
commit b01531db6cec2aa330dbc91bfbfaaef4a0d387a4 upstream.

->lookup() in an encrypted directory begins as follows:

1. fscrypt_prepare_lookup():
    a. Try to load the directory's encryption key.
    b. If the key is unavailable, mark the dentry as a ciphertext name
       via d_flags.
2. fscrypt_setup_filename():
    a. Try to load the directory's encryption key.
    b. If the key is available, encrypt the name (treated as a plaintext
       name) to get the on-disk name.  Otherwise decode the name
       (treated as a ciphertext name) to get the on-disk name.

But if the key is concurrently added, it may be found at (2a) but not at
(1a).  In this case, the dentry will be wrongly marked as a ciphertext
name even though it was actually treated as plaintext.

This will cause the dentry to be wrongly invalidated on the next lookup,
potentially causing problems.  For example, if the racy ->lookup() was
part of sys_mount(), then the new mount will be detached when anything
tries to access it.  This is despite the mountpoint having a plaintext
path, which should remain valid now that the key was added.

Of course, this is only possible if there's a userspace race.  Still,
the additional kernel-side race is confusing and unexpected.

Close the kernel-side race by changing fscrypt_prepare_lookup() to also
set the on-disk filename (step 2b), consistent with the d_flags update.

Fixes: 28b4c263961c ("ext4 crypto: revalidate dentry after adding or removing the key")
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>
2020-11-05 11:08:35 +01:00
Liu Song
2f0a77ccae ubifs: Fix out-of-bounds memory access caused by abnormal value of node_len
[ Upstream commit acc5af3efa303d5f36cc8c0f61716161f6ca1384 ]

In “ubifs_check_node”, when the value of "node_len" is abnormal,
the code will goto label of "out_len" for execution. Then, in the
following "ubifs_dump_node", if inode type is "UBIFS_DATA_NODE",
in "print_hex_dump", an out-of-bounds access may occur due to the
wrong "ch->len".

Therefore, when the value of "node_len" is abnormal, data length
should to be adjusted to a reasonable safe range. At this time,
structured data is not credible, so dump the corrupted data directly
for analysis.

Signed-off-by: Liu Song <liu.song11@zte.com.cn>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 13:14:40 +02:00
Christoph Hellwig
e0fdf46af9 ubifs: remove broken lazytime support
[ Upstream commit ecf84096a526f2632ee85c32a3d05de3fa60ce80 ]

When "ubifs: introduce UBIFS_ATIME_SUPPORT to ubifs" introduced atime
support to ubifs, it also added lazytime support.  As far as I can tell
the lazytime support is terminally broken, as it causes
mark_inode_dirty_sync to be called from __writeback_single_inode, which
will then trigger the locking assert in ubifs_dirty_inode.  Just remove
the broken lazytime support for now, it can be added back later,
especially as some infrastructure changes should make that easier soon.

Fixes: 8c1c5f263833 ("ubifs: introduce UBIFS_ATIME_SUPPORT to ubifs")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 17:37:30 +02:00
Zhihao Cheng
81f076b88f ubifs: Fix deadlock in concurrent bulk-read and writepage
commit f5de5b83303e61b1f3fb09bd77ce3ac2d7a475f2 upstream.

In ubifs, concurrent execution of writepage and bulk read on the same file
may cause ABBA deadlock, for example (Reproduce method see Link):

Process A(Bulk-read starts from page4)         Process B(write page4 back)
  vfs_read                                       wb_workfn or fsync
  ...                                            ...
  generic_file_buffered_read                     write_cache_pages
    ubifs_readpage                                 LOCK(page4)

      ubifs_bulk_read                              ubifs_writepage
        LOCK(ui->ui_mutex)                           ubifs_write_inode

	  ubifs_do_bulk_read                           LOCK(ui->ui_mutex)
	    find_or_create_page(alloc page4)                  ↑
	      LOCK(page4)                   <--     ABBA deadlock occurs!

In order to ensure the serialization execution of bulk read, we can't
remove the big lock 'ui->ui_mutex' in ubifs_bulk_read(). Instead, we
allow ubifs_do_bulk_read() to lock page failed by replacing
find_or_create_page(FGP_LOCK) with
pagecache_get_page(FGP_LOCK | FGP_NOWAIT).

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Suggested-by: zhangyi (F) <yi.zhang@huawei.com>
Cc: <Stable@vger.kernel.org>
Fixes: 4793e7c5e1c ("UBIFS: add bulk-read facility")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206153
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:34:00 -08:00
Eric Biggers
4efec60cba ubifs: Fix FS_IOC_SETFLAGS unexpectedly clearing encrypt flag
commit 2b57067a7778484c10892fa191997bfda29fea13 upstream.

UBIFS's implementation of FS_IOC_SETFLAGS fails to preserve existing
inode flags that aren't settable by FS_IOC_SETFLAGS, namely the encrypt
flag.  This causes the encrypt flag to be unexpectedly cleared.

Fix it by preserving existing unsettable flags, like ext4 and f2fs do.

Test case with kvm-xfstests shell:

    FSTYP=ubifs KEYCTL_PROG=keyctl
    . fs/ubifs/config
    . ~/xfstests/common/encrypt
    dev=$(__blkdev_to_ubi_volume /dev/vdc)
    ubiupdatevol -t $dev
    mount $dev /mnt -t ubifs
    k=$(_generate_session_encryption_key)
    mkdir /mnt/edir
    xfs_io -c "set_encpolicy $k" /mnt/edir
    echo contents > /mnt/edir/file
    chattr +i /mnt/edir/file
    chattr -i /mnt/edir/file

With the bug, the following errors occur on the last command:

    [   18.081559] fscrypt (ubifs, inode 67): Inconsistent encryption context (parent directory: 65)
    chattr: Operation not permitted while reading flags on /mnt/edir/file

Fixes: d475a507457b ("ubifs: Add skeleton for fscrypto")
Cc: <stable@vger.kernel.org> # v4.10+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:34:00 -08:00
Eric Biggers
03e032cb56 ubifs: don't trigger assertion on invalid no-key filename
commit f0d07a98a070bb5e443df19c3aa55693cbca9341 upstream.

If userspace provides an invalid fscrypt no-key filename which encodes a
hash value with any of the UBIFS node type bits set (i.e. the high 3
bits), gracefully report ENOENT rather than triggering ubifs_assert().

Test case with kvm-xfstests shell:

    . fs/ubifs/config
    . ~/xfstests/common/encrypt
    dev=$(__blkdev_to_ubi_volume /dev/vdc)
    ubiupdatevol $dev -t
    mount $dev /mnt -t ubifs
    mkdir /mnt/edir
    xfs_io -c set_encpolicy /mnt/edir
    rm /mnt/edir/_,,,,,DAAAAAAAAAAAAAAAAAAAAAAAAAA

With the bug, the following assertion fails on the 'rm' command:

    [   19.066048] UBIFS error (ubi0:0 pid 379): ubifs_assert_failed: UBIFS assert failed: !(hash & ~UBIFS_S_KEY_HASH_MASK), in fs/ubifs/key.h:170

Fixes: f4f61d2cc6d8 ("ubifs: Implement encrypted filenames")
Cc: <stable@vger.kernel.org> # v4.10+
Link: https://lore.kernel.org/r/20200120223201.241390-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:34:00 -08:00
Hou Tao
08ae5ec4be ubifs: Reject unsupported ioctl flags explicitly
commit 2fe8b2d5578d7d142982e3bf62e4c0caf8b8fe02 upstream.

Reject unsupported ioctl flags explicitly, so the following command
on a regular ubifs file will fail:
	chattr +d ubifs_file

And xfstests generic/424 will pass.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:34:00 -08:00
Zhihao Cheng
7764ed0b72 ubifs: ubifs_tnc_start_commit: Fix OOB in layout_in_gaps
[ Upstream commit 6abf57262166b4f4294667fb5206ae7ba1ba96f5 ]

Running stress-test test_2 in mtd-utils on ubi device, sometimes we can
get following oops message:

  BUG: unable to handle page fault for address: ffffffff00000140
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 280a067 P4D 280a067 PUD 0
  Oops: 0000 [#1] SMP
  CPU: 0 PID: 60 Comm: kworker/u16:1 Kdump: loaded Not tainted 5.2.0 #13
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0
  -0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  Workqueue: writeback wb_workfn (flush-ubifs_0_0)
  RIP: 0010:rb_next_postorder+0x2e/0xb0
  Code: 80 db 03 01 48 85 ff 0f 84 97 00 00 00 48 8b 17 48 83 05 bc 80 db
  03 01 48 83 e2 fc 0f 84 82 00 00 00 48 83 05 b2 80 db 03 01 <48> 3b 7a
  10 48 89 d0 74 02 f3 c3 48 8b 52 08 48 83 05 a3 80 db 03
  RSP: 0018:ffffc90000887758 EFLAGS: 00010202
  RAX: ffff888129ae4700 RBX: ffff888138b08400 RCX: 0000000080800001
  RDX: ffffffff00000130 RSI: 0000000080800024 RDI: ffff888138b08400
  RBP: ffff888138b08400 R08: ffffea0004a6b920 R09: 0000000000000000
  R10: ffffc90000887740 R11: 0000000000000001 R12: ffff888128d48000
  R13: 0000000000000800 R14: 000000000000011e R15: 00000000000007c8
  FS:  0000000000000000(0000) GS:ffff88813ba00000(0000)
  knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: ffffffff00000140 CR3: 000000013789d000 CR4: 00000000000006f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
    destroy_old_idx+0x5d/0xa0 [ubifs]
    ubifs_tnc_start_commit+0x4fe/0x1380 [ubifs]
    do_commit+0x3eb/0x830 [ubifs]
    ubifs_run_commit+0xdc/0x1c0 [ubifs]

Above Oops are due to the slab-out-of-bounds happened in do-while of
function layout_in_gaps indirectly called by ubifs_tnc_start_commit. In
function layout_in_gaps, there is a do-while loop placing index nodes
into the gaps created by obsolete index nodes in non-empty index LEBs
until rest index nodes can totally be placed into pre-allocated empty
LEBs. @c->gap_lebs points to a memory area(integer array) which records
LEB numbers used by 'in-the-gaps' method. Whenever a fitable index LEB
is found, corresponding lnum will be incrementally written into the
memory area pointed by @c->gap_lebs. The size
((@c->lst.idx_lebs + 1) * sizeof(int)) of memory area is allocated before
do-while loop and can not be changed in the loop. But @c->lst.idx_lebs
could be increased by function ubifs_change_lp (called by
layout_leb_in_gaps->ubifs_find_dirty_idx_leb->get_idx_gc_leb) during the
loop. So, sometimes oob happens when number of cycles in do-while loop
exceeds the original value of @c->lst.idx_lebs. See detail in
https://bugzilla.kernel.org/show_bug.cgi?id=204229.
This patch fixes oob in layout_in_gaps.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-09 10:19:09 +01:00
Gabor Juhos
c7f81d70d7 ubifs: Fix default compression selection in ubifs
[ Upstream commit d62e98ed1efcaa94caa004f622944afdce5f1c3c ]

When ubifs is build without the LZO compressor and no compressor is
given the creation of the default file system will fail. before
selection the LZO compressor check if it is present and if not fall back
to the zlib or none.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-05 09:20:09 +01:00
Richard Weinberger
72cd230b32 ubifs: Correctly use tnc_next() in search_dh_cookie()
commit bacfa94b08027b9f66ede7044972e3b066766b3e upstream.

Commit c877154d307f fixed an uninitialized variable and optimized
the function to not call tnc_next() in the first iteration of the
loop. While this seemed perfectly legit and wise, it turned out to
be illegal.
If the lookup function does not find an exact match it will rewind
the cursor by 1.
The rewinded cursor will not match the name hash we are looking for
and this results in a spurious -ENOENT.
So we need to move to the next entry in case of an non-exact match,
but not if the match was exact.

While we are here, update the documentation to avoid further confusion.

Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: c877154d307f ("ubifs: Fix uninitialized variable in search_dh_cookie()")
Fixes: 781f675e2d7e ("ubifs: Fix unlink code wrt. double hash lookups")
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-19 09:09:37 +02:00
Richard Weinberger
0736458856 ubifs: Handle re-linking of inodes correctly while recovery
commit e58725d51fa8da9133f3f1c54170aa2e43056b91 upstream.

UBIFS's recovery code strictly assumes that a deleted inode will never
come back, therefore it removes all data which belongs to that inode
as soon it faces an inode with link count 0 in the replay list.
Before O_TMPFILE this assumption was perfectly fine. With O_TMPFILE
it can lead to data loss upon a power-cut.

Consider a journal with entries like:
0: inode X (nlink = 0) /* O_TMPFILE was created */
1: data for inode X /* Someone writes to the temp file */
2: inode X (nlink = 0) /* inode was changed, xattr, chmod, … */
3: inode X (nlink = 1) /* inode was re-linked via linkat() */

Upon replay of entry #2 UBIFS will drop all data that belongs to inode X,
this will lead to an empty file after mounting.

As solution for this problem, scan the replay list for a re-link entry
before dropping data.

Fixes: 474b93704f32 ("ubifs: Implement O_TMPFILE")
Cc: stable@vger.kernel.org
Cc: Russell Senior <russell@personaltelco.net>
Cc: Rafał Miłecki <zajec5@gmail.com>
Reported-by: Russell Senior <russell@personaltelco.net>
Reported-by: Rafał Miłecki <zajec5@gmail.com>
Tested-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-29 13:37:55 +01:00
Richard Weinberger
f8ccb14fd6 ubifs: Fix WARN_ON logic in exit path
ubifs_assert() is not WARN_ON(), so we have to invert
the checks.
Randy faced this warning with UBIFS being a module, since
most users use UBIFS as builtin because UBIFS is the rootfs
nobody noticed so far. :-(
Including me.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: 54169ddd382d ("ubifs: Turn two ubifs_assert() into a WARN_ON()")
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-13 11:05:02 +02:00
Richard Weinberger
f061c1cc40 Revert "ubifs: xattr: Don't operate on deleted inodes"
This reverts commit 11a6fc3dc743e22fb50f2196ec55bee5140d3c52.
UBIFS wants to assert that xattr operations are only issued on files
with positive link count. The said patch made this operations return
-ENOENT for unlinked files such that the asserts will no longer trigger.
This was wrong since xattr operations are perfectly fine on unlinked
files.
Instead the assertions need to be fixed/removed.

Cc: <stable@vger.kernel.org>
Fixes: 11a6fc3dc743 ("ubifs: xattr: Don't operate on deleted inodes")
Reported-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-09-20 21:37:41 +02:00
Sascha Hauer
d3bdc016c5 ubifs: drop false positive assertion
The following sequence triggers

	ubifs_assert(c, c->lst.taken_empty_lebs > 0);

at the end of ubifs_remount_fs():

mount -t ubifs /dev/ubi0_0 /mnt
echo 1 > /sys/kernel/debug/ubifs/ubi0_0/ro_error
umount /mnt
mount -t ubifs -o ro /dev/ubix_y /mnt
mount -o remount,ro /mnt

The resulting

UBIFS assert failed in ubifs_remount_fs at 1878 (pid 161)

is a false positive. In the case above c->lst.taken_empty_lebs has
never been changed from its initial zero value. This will only happen
when the deferred recovery is done.

Fix this by doing the assertion only when recovery has been done
already.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-09-20 21:37:07 +02:00
Richard Weinberger
37f31b6ca4 ubifs: Check for name being NULL while mounting
The requested device name can be NULL or an empty string.
Check for that and refuse to continue. UBIFS has to do this manually
since we cannot use mount_bdev(), which checks for this condition.

Fixes: 1e51764a3c2ac ("UBIFS: add new flash file system")
Reported-by: syzbot+38bd0f7865e5c6379280@syzkaller.appspotmail.com
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-09-20 21:37:07 +02:00
Richard Weinberger
6e5461d774 ubifs: Remove empty file.h
This empty file sneaked into the tree by mistake.
Remove it.

Fixes: 6eb61d587f45 ("ubifs: Pass struct ubifs_info to ubifs_assert()")
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-24 13:50:07 +02:00
Richard Weinberger
99a24e02cc ubifs: Set default assert action to read-only
Traditionally UBIFS just reported a failed assertion and moved on. The
drawback is that users will notice UBIFS bugs when it is too late, most
of the time when it is no longer about to mount. This makes bug hunting
problematic since valuable information from failing asserts is long gone
when UBIFS is dead. The other extreme, panic'ing on a failing assert is
also not worthwhile, we want users and developers give a chance to
collect as much debugging information as possible if UBIFS hits an
assert. Therefore go for the third option, switch to read-only mode when
an assert fails. That way UBIFS will not write possible bad data to the
MTD and gives users the chance to collect debugging information.

Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15 00:25:22 +02:00
Richard Weinberger
c38c5a7f2e ubifs: Allow setting assert action as mount parameter
Expose our three options to userspace.

Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15 00:25:21 +02:00
Richard Weinberger
2e52eb7446 ubifs: Rework ubifs_assert()
With having access to struct ubifs_info in ubifs_assert() we can
give more information when an assert is failing.
By using ubifs_err() we can tell which UBIFS instance failed.

Also multiple actions can be taken now.
We support:
 - report: This is what UBIFS did so far, just report the failure and go
   on.
 - read-only: Switch to read-only mode.
 - panic: shoot the kernel in the head.

Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15 00:25:21 +02:00
Richard Weinberger
6eb61d587f ubifs: Pass struct ubifs_info to ubifs_assert()
This allows us to have more context in ubifs_assert()
and take different actions depending on the configuration.

Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15 00:25:21 +02:00
Richard Weinberger
54169ddd38 ubifs: Turn two ubifs_assert() into a WARN_ON()
We are going to pass struct ubifs_info to ubifs_assert()
but while unloading the UBIFS module we don't have the info
struct anymore.
Therefore replace the asserts by a regular WARN_ON().

Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15 00:25:21 +02:00
Richard Weinberger
a3d218280c ubifs: Use kmalloc_array()
Since commit 6da2ec56059c ("treewide: kmalloc() -> kmalloc_array()")
we use kmalloc_array() for kmalloc() that computes the length with
a multiplication.

Cc: Kees Cook <keescook@chromium.org>
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15 00:25:20 +02:00
Richard Weinberger
95a22d2084 ubifs: Check data node size before truncate
Check whether the size is within bounds before using it.
If the size is not correct, abort and dump the bad data node.

Cc: Kees Cook <keescook@chromium.org>
Cc: Silvio Cesare <silvio.cesare@gmail.com>
Cc: stable@vger.kernel.org
Fixes: 1e51764a3c2ac ("UBIFS: add new flash file system")
Reported-by: Silvio Cesare <silvio.cesare@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15 00:25:20 +02:00