linux-stable.git/fs/exfat, branch linux-6.10.y

exfat: fix memory leak in exfat_load_bitmap()

2024-10-10T10:00:57+00:00

commit d2b537b3e533f28e0d97293fe9293161fe8cd137 upstream.

If the first directory entry in the root directory is not a bitmap
directory entry, 'bh' will not be released and reassigned, which
will cause a memory leak.

Fixes: 1e49a94cf707 ("exfat: add bitmap operations")
Cc: stable@vger.kernel.org
Signed-off-by: Yuezhang Mo 
Reviewed-by: Aoyama Wataru 
Signed-off-by: Namjae Jeon 
Signed-off-by: Greg Kroah-Hartman

exfat: resolve memory leak from exfat_create_upcase_table()

2024-10-04T14:33:47+00:00

commit c290fe508eee36df1640c3cb35dc8f89e073c8a8 upstream.

If exfat_load_upcase_table reaches end and returns -EINVAL,
allocated memory doesn't get freed and while
exfat_load_default_upcase_table allocates more memory, leading to a
memory leak.

Here's link to syzkaller crash report illustrating this issue:
https://syzkaller.appspot.com/text?tag=CrashReport&x=1406c201980000

Reported-by: syzbot+e1c69cadec0f1a078e3d@syzkaller.appspotmail.com
Fixes: a13d1a4de3b0 ("exfat: move freeing sbi, upcase table and dropping nls into rcu-delayed helper")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Yang 
Signed-off-by: Namjae Jeon 
Signed-off-by: Greg Kroah-Hartman

exfat: fix potential deadlock on __exfat_get_dentry_set

2024-08-03T07:00:30+00:00

commit 89fc548767a2155231128cb98726d6d2ea1256c9 upstream.

When accessing a file with more entries than ES_MAX_ENTRY_NUM, the bh-array
is allocated in __exfat_get_entry_set. The problem is that the bh-array is
allocated with GFP_KERNEL. It does not make sense. In the following cases,
a deadlock for sbi->s_lock between the two processes may occur.

       CPU0                CPU1
       ----                ----
  kswapd
   balance_pgdat
    lock(fs_reclaim)
                      exfat_iterate
                       lock(&sbi->s_lock)
                       exfat_readdir
                        exfat_get_uniname_from_ext_entry
                         exfat_get_dentry_set
                          __exfat_get_dentry_set
                           kmalloc_array
                            ...
                            lock(fs_reclaim)
    ...
    evict
     exfat_evict_inode
      lock(&sbi->s_lock)

To fix this, let's allocate bh-array with GFP_NOFS.

Fixes: a3ff29a95fde ("exfat: support dynamic allocate bh for exfat_entry_set_cache")
Cc: stable@vger.kernel.org # v6.2+
Reported-by: syzbot+412a392a2cd4a65e71db@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/lkml/000000000000fef47e0618c0327f@google.com
Signed-off-by: Sungjong Seo 
Signed-off-by: Namjae Jeon 
Signed-off-by: Greg Kroah-Hartman

exfat: zero the reserved fields of file and stream extension dentries

2024-04-25T12:59:59+00:00

From exFAT specification, the reserved fields should initialize
to zero and should not use for any purpose.

If create a new dentry set in the UNUSED dentries, all fields
had been zeroed when allocating cluster to parent directory.

But if create a new dentry set in the DELETED dentries, the
reserved fields in file and stream extension dentries may be
non-zero. Because only the valid bit of the type field of the
dentry is cleared in exfat_remove_entries(), if the type of
dentry is different from the original(For example, a dentry that
was originally a file name dentry, then set to deleted dentry,
and then set as a file dentry), the reserved fields is non-zero.

So this commit initializes the dentry to 0 before createing file
dentry and stream extension dentry.

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

exfat: fix timing of synchronizing bitmap and inode

2024-03-31T14:39:29+00:00

Commit(f55c096f62f1 exfat: do not zero the extended part) changed
the timing of synchronizing bitmap and inode in exfat_cont_expand().
The change caused xfstests generic/013 to fail if 'dirsync' or 'sync'
is enabled. So this commit restores the timing.

Fixes: f55c096f62f1 ("exfat: do not zero the extended part")
Signed-off-by: Yuezhang Mo 
Signed-off-by: Namjae Jeon

Merge tag 'exfat-for-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat

2024-03-21T16:47:12+00:00

Pull exfat updates from Namjae Jeon:

 - Improve dirsync performance by syncing on a dentry-set rather than on
   a per-directory entry

* tag 'exfat-for-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
  exfat: remove duplicate update parent dir
  exfat: do not sync parent dir if just update timestamp
  exfat: remove unused functions
  exfat: convert exfat_find_empty_entry() to use dentry cache
  exfat: convert exfat_init_ext_entry() to use dentry cache
  exfat: move free cluster out of exfat_init_ext_entry()
  exfat: convert exfat_remove_entries() to use dentry cache
  exfat: convert exfat_add_entry() to use dentry cache
  exfat: add exfat_get_empty_dentry_set() helper
  exfat: add __exfat_get_dentry_set() helper

exfat: remove duplicate update parent dir

2024-03-19T11:56:10+00:00

For renaming, the directory only needs to be updated once if it
is in the same directory.

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

exfat: do not sync parent dir if just update timestamp

2024-03-19T11:56:05+00:00

When sync or dir_sync is enabled, there is no need to sync the
parent directory's inode if only for updating its timestamp.

1. If an unexpected power failure occurs, the timestamp of the
   parent directory is not updated to the storage, which has no
   impact on the user.

2. The number of writes will be greatly reduced, which can not
   only improve performance, but also prolong device life.

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

exfat: remove unused functions

2024-03-19T11:56:01+00:00

exfat_count_ext_entries() is no longer called, remove it.
exfat_update_dir_chksum() is no longer called, remove it and
rename exfat_update_dir_chksum_with_entry_set() to it.

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

exfat: convert exfat_find_empty_entry() to use dentry cache

2024-03-19T11:55:54+00:00

Before this conversion, each dentry traversed needs to be read
from the storage device or page cache. There are at least 16
dentries in a sector. This will result in frequent page cache
searches.

After this conversion, if all directory entries in a sector are
used, the sector only needs to be read once.

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