linux.git/fs/exfat, branch v5.19

exfat: use updated exfat_chain directly during renaming

2022-06-09T12:26:32+00:00

In order for a file to access its own directory entry set,
exfat_inode_info(ei) has two copied values. One is ei->dir, which is
a snapshot of exfat_chain of the parent directory, and the other is
ei->entry, which is the offset of the start of the directory entry set
in the parent directory.

Since the parent directory can be updated after the snapshot point,
it should be used only for accessing one's own directory entry set.

However, as of now, during renaming, it could try to traverse or to
allocate clusters via snapshot values, it does not make sense.

This potential problem has been revealed when exfat_update_parent_info()
was removed by commit d8dad2588add ("exfat: fix referencing wrong parent
directory information after renaming"). However, I don't think it's good
idea to bring exfat_update_parent_info() back.

Instead, let's use the updated exfat_chain of parent directory diectly.

Fixes: d8dad2588add ("exfat: fix referencing wrong parent directory information after renaming")
Reported-by: Wang Yugui 
Signed-off-by: Sungjong Seo 
Tested-by: Wang Yugui 
Signed-off-by: Namjae Jeon

Merge tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache

2022-05-25T02:55:07+00:00

Pull page cache updates from Matthew Wilcox:

 - Appoint myself page cache maintainer

 - Fix how scsicam uses the page cache

 - Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS

 - Remove the AOP flags entirely

 - Remove pagecache_write_begin() and pagecache_write_end()

 - Documentation updates

 - Convert several address_space operations to use folios:
     - is_dirty_writeback
     - readpage becomes read_folio
     - releasepage becomes release_folio
     - freepage becomes free_folio

 - Change filler_t to require a struct file pointer be the first
   argument like ->read_folio

* tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache: (107 commits)
  nilfs2: Fix some kernel-doc comments
  Appoint myself page cache maintainer
  fs: Remove aops->freepage
  secretmem: Convert to free_folio
  nfs: Convert to free_folio
  orangefs: Convert to free_folio
  fs: Add free_folio address space operation
  fs: Convert drop_buffers() to use a folio
  fs: Change try_to_free_buffers() to take a folio
  jbd2: Convert release_buffer_page() to use a folio
  jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio
  reiserfs: Convert release_buffer_page() to use a folio
  fs: Remove last vestiges of releasepage
  ubifs: Convert to release_folio
  reiserfs: Convert to release_folio
  orangefs: Convert to release_folio
  ocfs2: Convert to release_folio
  nilfs2: Remove comment about releasepage
  nfs: Convert to release_folio
  jfs: Convert to release_folio
  ...

Merge tag 'exfat-for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat

2022-05-25T01:30:27+00:00

Pull exfat updates from Namjae Jeon:

 - fix referencing wrong parent directory information during rename

 - introduce a sys_tz mount option to use system timezone

 - improve performance while zeroing a cluster with dirsync mount option

 - fix slab-out-bounds in exat_clear_bitmap() reported from syzbot

* tag 'exfat-for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
  exfat: check if cluster num is valid
  exfat: reduce block requests when zeroing a cluster
  block: add sync_blockdev_range()
  exfat: introduce mount option 'sys_tz'
  exfat: fix referencing wrong parent directory information after renaming

exfat: check if cluster num is valid

2022-05-23T02:17:30+00:00

Syzbot reported slab-out-of-bounds read in exfat_clear_bitmap.
This was triggered by reproducer calling truncute with size 0,
which causes the following trace:

BUG: KASAN: slab-out-of-bounds in exfat_clear_bitmap+0x147/0x490 fs/exfat/balloc.c:174
Read of size 8 at addr ffff888115aa9508 by task syz-executor251/365

Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118
 print_address_description+0x81/0x3c0 mm/kasan/report.c:233
 __kasan_report mm/kasan/report.c:419 [inline]
 kasan_report+0x1a4/0x1f0 mm/kasan/report.c:436
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
 exfat_clear_bitmap+0x147/0x490 fs/exfat/balloc.c:174
 exfat_free_cluster+0x25a/0x4a0 fs/exfat/fatent.c:181
 __exfat_truncate+0x99e/0xe00 fs/exfat/file.c:217
 exfat_truncate+0x11b/0x4f0 fs/exfat/file.c:243
 exfat_setattr+0xa03/0xd40 fs/exfat/file.c:339
 notify_change+0xb76/0xe10 fs/attr.c:336
 do_truncate+0x1ea/0x2d0 fs/open.c:65

Move the is_valid_cluster() helper from fatent.c to a common
header to make it reusable in other *.c files. And add is_valid_cluster()
to validate if cluster number is within valid range in exfat_clear_bitmap()
and exfat_set_bitmap().

Link: https://syzkaller.appspot.com/bug?id=50381fc73821ecae743b8cf24b4c9a04776f767c
Reported-by: syzbot+a4087e40b9c13aad7892@syzkaller.appspotmail.com
Fixes: 1e49a94cf707 ("exfat: add bitmap operations")
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Tadeusz Struk 
Reviewed-by: Sungjong Seo 
Signed-off-by: Namjae Jeon

exfat: reduce block requests when zeroing a cluster

2022-05-23T02:17:30+00:00

If 'dirsync' is enabled, when zeroing a cluster, submitting
sector by sector will generate many block requests, will
cause the block device to not fully perform its performance.

This commit makes the sectors in a cluster to be submitted in
once, it will reduce the number of block requests. This will
make the block device to give full play to its performance.

Test create 1000 directories on SD card with:

$ time (for ((i=0;i<1000;i++)); do mkdir dir${i}; done)

Performance has been improved by more than 73% on imx6q-sabrelite.

Cluster size       Before         After       Improvement
64  KBytes         3m34.036s      0m56.052s   73.8%
128 KBytes         6m2.644s       1m13.354s   79.8%
256 KBytes         11m22.202s     1m39.451s   85.4%

imx6q-sabrelite:
  - CPU: 792 MHz x4
  - Memory: 1GB DDR3
  - SD Card: SanDisk 8GB Class 4

Signed-off-by: Yuezhang Mo 
Reviewed-by: Andy Wu 
Reviewed-by: Aoyama Wataru 
Reviewed-by: Christoph Hellwig 
Acked-by: Sungjong Seo 
Signed-off-by: Namjae Jeon

exfat: introduce mount option 'sys_tz'

2022-05-23T02:17:29+00:00

EXFAT_TZ_VALID bit in {create,modify,access}_tz is corresponding to
OffsetValid field in exfat specification [1]. When this bit isn't
set, timestamps should be treated as having the same UTC offset as
the current local time.

Currently, there is an option 'time_offset' for users to specify the
UTC offset for this issue. This patch introduces a new mount option
'sys_tz' to use system timezone as time offset.

Link: [1] https://docs.microsoft.com/en-us/windows/win32/fileio/exfat-specification#74102-offsetvalid-field

Signed-off-by: Chung-Chiang Cheng 
Acked-by: Sungjong Seo 
Signed-off-by: Namjae Jeon

exfat: fix referencing wrong parent directory information after renaming

2022-05-23T02:17:29+00:00

During renaming, the parent directory information maybe
updated. But the file/directory still references to the
old parent directory information.

This bug will cause 2 problems.

(1) The renamed file can not be written.

    [10768.175172] exFAT-fs (sda1): error, failed to bmap (inode : 7afd50e4 iblock : 0, err : -5)
    [10768.184285] exFAT-fs (sda1): Filesystem has been set read-only
    ash: write error: Input/output error

(2) Some dentries of the renamed file/directory are not set
    to deleted after removing the file/directory.

exfat_update_parent_info() is a workaround for the wrong parent
directory information being used after renaming. Now that bug is
fixed, this is no longer needed, so remove it.

Fixes: 5f2aa075070c ("exfat: add inode operations")
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Yuezhang Mo 
Reviewed-by: Andy Wu 
Reviewed-by: Aoyama Wataru 
Reviewed-by: Daniel Palmer 
Reviewed-by: Sungjong Seo 
Signed-off-by: Namjae Jeon

fs: Convert mpage_readpage to mpage_read_folio

2022-05-09T20:21:44+00:00

mpage_readpage still works in terms of pages, and has not been audited
for correctness with large folios, so include an assertion that the
filesystem is not passing it large folios.  Convert all the filesystems
to call mpage_read_folio() instead of mpage_readpage().

Signed-off-by: Matthew Wilcox (Oracle)

fs: Remove flags parameter from aops->write_begin

2022-05-08T18:28:19+00:00

There are no more aop flags left, so remove the parameter.

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Christoph Hellwig

fs: Remove aop flags parameter from cont_write_begin()

2022-05-08T18:28:19+00:00

There are no more aop flags left, so remove the parameter.

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Christoph Hellwig