Commit graph

6 commits

Author SHA1 Message Date
Sungjong Seo
cec3c7c380 exfat: fix potential deadlock on __exfat_get_dentry_set
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 <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
[Sherry: The problematic commit was backported to 5.15.y and 5.10.y, thus backport this fix]
Signed-off-by: Sherry Yang <sherry.yang@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-02 17:00:49 +01:00
Namjae Jeon
37cd387ec9 exfat: fix uninit-value in __exfat_get_dentry_set
commit 02dffe9ab092fc4c8800aee68cb7eafd37a980c4 upstream.

There is no check if stream size and start_clu are invalid.
If start_clu is EOF cluster and stream size is 4096, It will
cause uninit value access. because ei->hint_femp.eidx could
be 128(if cluster size is 4K) and wrong hint will allocate
next cluster. and this cluster will be same with the cluster
that is allocated by exfat_extend_valid_size(). The previous
patch will check invalid start_clu, but for clarity, initialize
hint_femp.eidx to zero.

Cc: stable@vger.kernel.org
Reported-by: syzbot+01218003be74b5e1213a@syzkaller.appspotmail.com
Tested-by: syzbot+01218003be74b5e1213a@syzkaller.appspotmail.com
Reviewed-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-17 13:24:18 +01:00
Ksawlii
5ef504acd1 Revert "exfat: fix memory leak in exfat_load_bitmap()"
This reverts commit defa602d2c.
2024-11-24 00:23:02 +01:00
Yuezhang Mo
defa602d2c exfat: fix memory leak in exfat_load_bitmap()
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 <Yuezhang.Mo@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:45 +01:00
Yuezhang Mo
cc5de197bc exfat: support handle zero-size directory
[ Upstream commit dab48b8f2fe7264d51ec9eed0adea0fe3c78830a ]

After repairing a corrupted file system with exfatprogs' fsck.exfat,
zero-size directories may result. It is also possible to create
zero-size directories in other exFAT implementation, such as Paragon
ufsd dirver.

As described in the specification, the lower directory size limits
is 0 bytes.

Without this commit, sub-directories and files cannot be created
under a zero-size directory, and it cannot be removed.

Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 11:43:14 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00