Commit Graph

236 Commits

Author SHA1 Message Date
Shuhao Fu
fc9ce76252 exfat: fix refcount leak in exfat_find
[ Upstream commit 9aee8de970 ]

Fix refcount leaks in `exfat_find` related to `exfat_get_dentry_set`.

Function `exfat_get_dentry_set` would increase the reference counter of
`es->bh` on success. Therefore, `exfat_put_dentry_set` must be called
after `exfat_get_dentry_set` to ensure refcount consistency. This patch
relocate two checks to avoid possible leaks.

Fixes: 82ebecdc74 ("exfat: fix improper check of dentry.stream.valid_size")
Fixes: 13940cef95 ("exfat: add a check for invalid data size")
Signed-off-by: Shuhao Fu <sfual@cse.ust.hk>
Reviewed-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Li hongliang <1468888505@139.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-30 10:28:48 +01:00
Yuezhang Mo
28442546f2 exfat: zero out post-EOF page cache on file extension
[ Upstream commit 4e163c39dd ]

xfstests generic/363 was failing due to unzeroed post-EOF page
cache that allowed mmap writes beyond EOF to become visible
after file extension.

For example, in following xfs_io sequence, 0x22 should not be
written to the file but would become visible after the extension:

  xfs_io -f -t -c "pwrite -S 0x11 0 8" \
    -c "mmap 0 4096" \
    -c "mwrite -S 0x22 32 32" \
    -c "munmap" \
    -c "pwrite -S 0x33 512 32" \
    $testfile

This violates the expected behavior where writes beyond EOF via
mmap should not persist after the file is extended. Instead, the
extended region should contain zeros.

Fix this by using truncate_pagecache() to truncate the page cache
after the current EOF when extending the file.

Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-08 10:14:11 +01:00
Yuezhang Mo
df3ca04116 exfat: fix remount failure in different process environments
[ Upstream commit 51fc7b4ce1 ]

The kernel test robot reported that the exFAT remount operation
failed. The reason for the failure was that the process's umask
is different between mount and remount, causing fs_fmask and
fs_dmask are changed.

Potentially, both gid and uid may also be changed. Therefore, when
initializing fs_context for remount, inherit these mount options
from the options used during mount.

Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202511251637.81670f5c-lkp@intel.com
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-08 10:14:11 +01:00
Yongpeng Yang
93c8a03a10 exfat: check return value of sb_min_blocksize in exfat_read_boot_sector
commit f2c1f63163 upstream.

sb_min_blocksize() may return 0. Check its return value to avoid
accessing the filesystem super block when sb->s_blocksize is 0.

Cc: stable@vger.kernel.org # v6.15
Fixes: 719c1e1829 ("exfat: add super block operations")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Link: https://patch.msgid.link/20251104125009.2111925-3-yangyongpeng.storage@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-12-01 11:43:21 +01:00
Jaehun Gou
6c627bcc18 exfat: fix improper check of dentry.stream.valid_size
[ Upstream commit 82ebecdc74 ]

We found an infinite loop bug in the exFAT file system that can lead to a
Denial-of-Service (DoS) condition. When a dentry in an exFAT filesystem is
malformed, the following system calls — SYS_openat, SYS_ftruncate, and
SYS_pwrite64 — can cause the kernel to hang.

Root cause analysis shows that the size validation code in exfat_find()
does not check whether dentry.stream.valid_size is negative. As a result,
the system calls mentioned above can succeed and eventually trigger the DoS
issue.

This patch adds a check for negative dentry.stream.valid_size to prevent
this vulnerability.

Co-developed-by: Seunghun Han <kkamagui@gmail.com>
Signed-off-by: Seunghun Han <kkamagui@gmail.com>
Co-developed-by: Jihoon Kwon <jimmyxyz010315@gmail.com>
Signed-off-by: Jihoon Kwon <jimmyxyz010315@gmail.com>
Signed-off-by: Jaehun Gou <p22gone@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-24 10:35:48 +01:00
Namjae Jeon
6bc58b4c53 exfat: validate cluster allocation bits of the allocation bitmap
[ Upstream commit 79c1587b6c ]

syzbot created an exfat image with cluster bits not set for the allocation
bitmap. exfat-fs reads and uses the allocation bitmap without checking
this. The problem is that if the start cluster of the allocation bitmap
is 6, cluster 6 can be allocated when creating a directory with mkdir.
exfat zeros out this cluster in exfat_mkdir, which can delete existing
entries. This can reallocate the allocated entries. In addition,
the allocation bitmap is also zeroed out, so cluster 6 can be reallocated.
This patch adds exfat_test_bitmap_range to validate that clusters used for
the allocation bitmap are correctly marked as in-use.

Reported-by: syzbot+a725ab460fc1def9896f@syzkaller.appspotmail.com
Tested-by: syzbot+a725ab460fc1def9896f@syzkaller.appspotmail.com
Reviewed-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-13 15:34:31 -05:00
Chi Zhiling
a76aba65e8 exfat: limit log print for IO error
[ Upstream commit 6dfba10838 ]

For exFAT filesystems with 4MB read_ahead_size, removing the storage device
when the read operation is in progress, which cause the last read syscall
spent 150s [1]. The main reason is that exFAT generates excessive log
messages [2].

After applying this patch, approximately 300,000 lines of log messages
were suppressed, and the delay of the last read() syscall was reduced
to about 4 seconds.

[1]:
write(5, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 131072) = 131072 <0.000120>
read(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 131072) = 131072 <0.000032>
write(5, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 131072) = 131072 <0.000119>
read(4, 0x7fccf28ae000, 131072)         = -1 EIO (Input/output error) <150.186215>

[2]:
[  333.696603] exFAT-fs (vdb): error, failed to access to FAT (entry 0x0000d780, err:-5)
[  333.697378] exFAT-fs (vdb): error, failed to access to FAT (entry 0x0000d780, err:-5)
[  333.698156] exFAT-fs (vdb): error, failed to access to FAT (entry 0x0000d780, err:-5)

Signed-off-by: Chi Zhiling <chizhiling@kylinos.cn>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-13 15:34:31 -05:00
Yuezhang Mo
aa8fe7b7b7 exfat: add cluster chain loop check for dir
[ Upstream commit 99f9a97dce ]

An infinite loop may occur if the following conditions occur due to
file system corruption.

(1) Condition for exfat_count_dir_entries() to loop infinitely.
    - The cluster chain includes a loop.
    - There is no UNUSED entry in the cluster chain.

(2) Condition for exfat_create_upcase_table() to loop infinitely.
    - The cluster chain of the root directory includes a loop.
    - There are no UNUSED entry and up-case table entry in the cluster
      chain of the root directory.

(3) Condition for exfat_load_bitmap() to loop infinitely.
    - The cluster chain of the root directory includes a loop.
    - There are no UNUSED entry and bitmap entry in the cluster chain
      of the root directory.

(4) Condition for exfat_find_dir_entry() to loop infinitely.
    - The cluster chain includes a loop.
    - The unused directory entries were exhausted by some operation.

(5) Condition for exfat_check_dir_empty() to loop infinitely.
    - The cluster chain includes a loop.
    - The unused directory entries were exhausted by some operation.
    - All files and sub-directories under the directory are deleted.

This commit adds checks to break the above infinite loop.

Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-20 18:30:47 +02:00
Zhengxu Zhang
6038537c4a exfat: fdatasync flag should be same like generic_write_sync()
[ Upstream commit 2f2d42a17b ]

Test: androbench by default setting, use 64GB sdcard.
 the random write speed:
	without this patch 3.5MB/s
	with this patch 7MB/s

After patch "11a347fb6cef", the random write speed decreased significantly.
the .write_iter() interface had been modified, and check the differences
with generic_file_write_iter(), when calling generic_write_sync() and
exfat_file_write_iter() to call vfs_fsync_range(), the fdatasync flag is
wrong, and make not use the fdatasync mode, and make random write speed
decreased. So use generic_write_sync() instead of vfs_fsync_range().

Fixes: 11a347fb6c ("exfat: change to get file size from DataLength")
Signed-off-by: Zhengxu Zhang <zhengxu.zhang@unisoc.com>
Acked-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:14:02 +02:00
Sungjong Seo
bab0bd1389 exfat: call bh_read in get_block only when necessary
[ Upstream commit c73e680d1f ]

With commit 11a347fb6c ("exfat: change to get file size from DataLength"),
exfat_get_block() can now handle valid_size. However, most partial
unwritten blocks that could be mapped with other blocks are being
inefficiently processed separately as individual blocks.

Except for partial unwritten blocks that require independent processing,
let's handle them simply as before.

Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
Reviewed-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29 11:02:03 +02:00
Sungjong Seo
37c9875c17 exfat: fix potential wrong error return from get_block
commit 59c30e3142 upstream.

If there is no error, get_block() should return 0. However, when bh_read()
returns 1, get_block() also returns 1 in the same manner.

Let's set err to 0, if there is no error from bh_read()

Fixes: 11a347fb6c ("exfat: change to get file size from DataLength")
Cc: stable@vger.kernel.org
Signed-off-by: Sungjong Seo <sj1557.seo@samsung.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>
2025-04-10 14:39:39 +02:00
Sungjong Seo
49b0a6ab8e exfat: fix random stack corruption after get_block
commit 1bb7ff4204 upstream.

When get_block is called with a buffer_head allocated on the stack, such
as do_mpage_readpage, stack corruption due to buffer_head UAF may occur in
the following race condition situation.

     <CPU 0>                      <CPU 1>
mpage_read_folio
  <<bh on stack>>
  do_mpage_readpage
    exfat_get_block
      bh_read
        __bh_read
	  get_bh(bh)
          submit_bh
          wait_on_buffer
                              ...
                              end_buffer_read_sync
                                __end_buffer_read_notouch
                                   unlock_buffer
          <<keep going>>
        ...
      ...
    ...
  ...
<<bh is not valid out of mpage_read_folio>>
   .
   .
another_function
  <<variable A on stack>>
                                   put_bh(bh)
                                     atomic_dec(bh->b_count)
  * stack corruption here *

This patch returns -EAGAIN if a folio does not have buffers when bh_read
needs to be called. By doing this, the caller can fallback to functions
like block_read_full_folio(), create a buffer_head in the folio, and then
call get_block again.

Let's do not call bh_read() with on-stack buffer_head.

Fixes: 11a347fb6c ("exfat: change to get file size from DataLength")
Cc: stable@vger.kernel.org
Tested-by: Yeongjin Gil <youngjin.gil@samsung.com>
Signed-off-by: Sungjong Seo <sj1557.seo@samsung.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>
2025-04-10 14:39:39 +02:00
Yuezhang Mo
9207575878 exfat: add a check for invalid data size
[ Upstream commit 13940cef95 ]

Add a check for invalid data size to avoid corrupted filesystem
from being further corrupted.

Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:30 +02:00
Yuezhang Mo
4a9595eb02 exfat: fix missing shutdown check
[ Upstream commit 47e35366bc ]

xfstests generic/730 test failed because after deleting the device
that still had dirty data, the file could still be read without
returning an error. The reason is the missing shutdown check in
->read_iter.

I also noticed that shutdown checks were missing from ->write_iter,
->splice_read, and ->mmap. This commit adds shutdown checks to all
of them.

Fixes: f761fcdd28 ("exfat: Implement sops->shutdown and ioctl")
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:26 +02:00
Yuezhang Mo
6a14075325 exfat: fix the infinite loop in exfat_find_last_cluster()
[ Upstream commit b0522303f6 ]

In exfat_find_last_cluster(), the cluster chain is traversed until
the EOF cluster. If the cluster chain includes a loop due to file
system corruption, the EOF cluster cannot be traversed, resulting
in an infinite loop.

If the number of clusters indicated by the file size is inconsistent
with the cluster chain length, exfat_find_last_cluster() will return
an error, so if this inconsistency is found, the traversal can be
aborted without traversing to the EOF cluster.

Reported-by: syzbot+f7d147e6db52b1e09dba@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=f7d147e6db52b1e09dba
Tested-by: syzbot+f7d147e6db52b1e09dba@syzkaller.appspotmail.com
Fixes: 31023864e6 ("exfat: add fat entry operations")
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:26 +02:00
Eric Sandeen
611015122d exfat: short-circuit zero-byte writes in exfat_file_write_iter
[ Upstream commit fda94a9919 ]

When generic_write_checks() returns zero, it means that
iov_iter_count() is zero, and there is no work to do.

Simply return success like all other filesystems do, rather than
proceeding down the write path, which today yields an -EFAULT in
generic_perform_write() via the
(fault_in_iov_iter_readable(i, bytes) == bytes) check when bytes
== 0.

Fixes: 11a347fb6c ("exfat: change to get file size from DataLength")
Reported-by: Noah <kernel-org-10@maxgrass.eu>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-13 13:02:08 +01:00
Namjae Jeon
c897b8ec46 exfat: fix soft lockup in exfat_clear_bitmap
[ Upstream commit 9da33619e0 ]

bitmap clear loop will take long time in __exfat_free_cluster()
if data size of file/dir enty is invalid.
If cluster bit in bitmap is already clear, stop clearing bitmap go to
out of loop.

Fixes: 31023864e6 ("exfat: add fat entry operations")
Reported-by: Kun Hu <huk23@m.fudan.edu.cn>, Jiaji Qin <jjtan24@m.fudan.edu.cn>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-13 13:02:08 +01:00
Yuezhang Mo
5d609f0d2f exfat: fix just enough dentries but allocate a new cluster to dir
[ Upstream commit 6697f819a1 ]

This commit fixes the condition for allocating cluster to parent
directory to avoid allocating new cluster to parent directory when
there are just enough empty directory entries at the end of the
parent directory.

Fixes: af02c72d0b ("exfat: convert exfat_find_empty_entry() to use dentry cache")
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-13 13:02:08 +01:00
Yuezhang Mo
0bebeb6672 exfat: fix the infinite loop in __exfat_free_cluster()
[ Upstream commit a5324b3a48 ]

In __exfat_free_cluster(), the cluster chain is traversed until the
EOF cluster. If the cluster chain includes a loop due to file system
corruption, the EOF cluster cannot be traversed, resulting in an
infinite loop.

This commit uses the total number of clusters to prevent this infinite
loop.

Reported-by: syzbot+1de5a37cb85a2d536330@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1de5a37cb85a2d536330
Tested-by: syzbot+1de5a37cb85a2d536330@syzkaller.appspotmail.com
Fixes: 31023864e6 ("exfat: add fat entry operations")
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-17 13:40:35 +01:00
Yuezhang Mo
942c6f91ab exfat: fix the new buffer was not zeroed before writing
[ Upstream commit 98e2fb26d1 ]

Before writing, if a buffer_head marked as new, its data must
be zeroed, otherwise uninitialized data in the page cache will
be written.

So this commit uses folio_zero_new_buffers() to zero the new
buffers before ->write_end().

Fixes: 6630ea4910 ("exfat: move extend valid_size into ->page_mkwrite()")
Reported-by: syzbot+91ae49e1c1a2634d20c0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=91ae49e1c1a2634d20c0
Tested-by: syzbot+91ae49e1c1a2634d20c0@syzkaller.appspotmail.com
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-17 13:40:35 +01:00
Yuezhang Mo
d9ea94f5cd exfat: fix the infinite loop in exfat_readdir()
[ Upstream commit fee873761b ]

If the file system is corrupted so that a cluster is linked to
itself in the cluster chain, and there is an unused directory
entry in the cluster, 'dentry' will not be incremented, causing
condition 'dentry < max_dentries' unable to prevent an infinite
loop.

This infinite loop causes s_lock not to be released, and other
tasks will hang, such as exfat_sync_fs().

This commit stops traversing the cluster chain when there is unused
directory entry in the cluster to avoid this infinite loop.

Reported-by: syzbot+205c2644abdff9d3f9fc@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=205c2644abdff9d3f9fc
Tested-by: syzbot+205c2644abdff9d3f9fc@syzkaller.appspotmail.com
Fixes: ca06197382 ("exfat: add directory operations")
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-17 13:40:35 +01:00
Yuezhang Mo
3ddd1cb2b4 exfat: fix out-of-bounds access of directory entries
commit 184fa506e3 upstream.

In the case of the directory size is greater than or equal to
the cluster size, if start_clu becomes an EOF cluster(an invalid
cluster) due to file system corruption, then the directory entry
where ei->hint_femp.eidx hint is outside the directory, resulting
in an out-of-bounds access, which may cause further file system
corruption.

This commit adds a check for start_clu, if it is an invalid cluster,
the file or directory will be treated as empty.

Cc: stable@vger.kernel.org
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Co-developed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:47 +01:00
Namjae Jeon
c500b0cca2 exfat: fix uninit-value in __exfat_get_dentry_set
commit 02dffe9ab0 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>
2024-12-05 14:02:47 +01:00
Yuezhang Mo
ad6e5bdca3 exfat: fix file being changed by unaligned direct write
[ Upstream commit 2e94e5bb94 ]

Unaligned direct writes are invalid and should return an error
without making any changes, rather than extending ->valid_size
and then returning an error. Therefore, alignment checking is
required before extending ->valid_size.

Fixes: 11a347fb6c ("exfat: change to get file size from DataLength")
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Co-developed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:02:31 +01:00
Al Viro
5f60d5f6bb move asm/unaligned.h to linux/unaligned.h
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.

auto-generated by the following:

for i in `git grep -l -w asm/unaligned.h`; do
	sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
	sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
2024-10-02 17:23:23 -04:00
Daniel Yang
c290fe508e exfat: resolve memory leak from exfat_create_upcase_table()
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: a13d1a4de3 ("exfat: move freeing sbi, upcase table and dropping nls into rcu-delayed helper")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Yang <danielyangkang@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-09-23 21:38:13 +09:00
Yuezhang Mo
6630ea4910 exfat: move extend valid_size into ->page_mkwrite()
It is not a good way to extend valid_size to the end of the
mmap area by writing zeros in mmap. Because after calling mmap,
no data may be written, or only a small amount of data may be
written to the head of the mmap area.

This commit moves extending valid_size to exfat_page_mkwrite().
In exfat_page_mkwrite() only extend valid_size to the starting
position of new data writing, which reduces unnecessary writing
of zeros.

If the block is not mapped and is marked as new after being
mapped for writing, block_write_begin() will zero the page
cache corresponding to the block, so there is no need to call
zero_user_segment() in exfat_file_zeroed_range(). And after moving
extending valid_size to exfat_page_mkwrite(), the data written by
mmap will be copied to the page cache but the page cache may be
not mapped to the disk. Calling zero_user_segment() will cause
the data written by mmap to be cleared. So this commit removes
calling zero_user_segment() from exfat_file_zeroed_range() and
renames exfat_file_zeroed_range() to exfat_extend_valid_size().

Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-09-23 21:38:11 +09:00
Yuezhang Mo
d2b537b3e5 exfat: fix memory leak in exfat_load_bitmap()
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: 1e49a94cf7 ("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>
2024-09-18 07:40:58 +09:00
Dongliang Cui
f761fcdd28 exfat: Implement sops->shutdown and ioctl
We found that when writing a large file through buffer write, if the
disk is inaccessible, exFAT does not return an error normally, which
leads to the writing process not stopping properly.

To easily reproduce this issue, you can follow the steps below:

1. format a device to exFAT and then mount (with a full disk erase)
2. dd if=/dev/zero of=/exfat_mount/test.img bs=1M count=8192
3. eject the device

You may find that the dd process does not stop immediately and may
continue for a long time.

The root cause of this issue is that during buffer write process,
exFAT does not need to access the disk to look up directory entries
or the FAT table (whereas FAT would do) every time data is written.
Instead, exFAT simply marks the buffer as dirty and returns,
delegating the writeback operation to the writeback process.

If the disk cannot be accessed at this time, the error will only be
returned to the writeback process, and the original process will not
receive the error, so it cannot be returned to the user side.

When the disk cannot be accessed normally, an error should be returned
to stop the writing process.

Implement sops->shutdown and ioctl to shut down the file system
when underlying block device is marked dead.

Signed-off-by: Dongliang Cui <dongliang.cui@unisoc.com>
Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-09-18 07:40:56 +09:00
Yuezhang Mo
231eb762bb exfat: do not fallback to buffered write
After commit(11a347fb6c exfat: change to get file size from
DataLength), the remaining area or hole had been filled with
zeros before calling exfat_direct_IO(), so there is no need to
fallback to buffered write, and ->i_size_aligned is no longer
needed, drop it.

Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-09-17 15:09:50 +09:00
Yuezhang Mo
fba27cf005 exfat: drop ->i_size_ondisk
->i_size_ondisk is no longer used by exfat_write_begin() after
commit(11a347fb6c exfat: change to get file size from DataLength),
drop it.

Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-09-17 14:46:51 +09:00
Matthew Wilcox (Oracle)
1da86618bd fs: Convert aops->write_begin to take a folio
Convert all callers from working on a page to working on one page
of a folio (support for working on an entire folio can come later).
Removes a lot of folio->page->folio conversions.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-08-07 11:33:21 +02:00
Matthew Wilcox (Oracle)
a225800f32 fs: Convert aops->write_end to take a folio
Most callers have a folio, and most implementations operate on a folio,
so remove the conversion from folio->page->folio to fit through this
interface.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-08-07 11:32:02 +02:00
Linus Torvalds
0260b0a744 Merge tag 'exfat-for-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat
Pull exfat updates from Namjae Jeon:

 - Fix deadlock issue reported by syzbot

 - Handle idmapped mounts

* tag 'exfat-for-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
  exfat: fix potential deadlock on __exfat_get_dentry_set
  exfat: handle idmapped mounts
2024-07-17 12:53:47 -07:00
Sungjong Seo
89fc548767 exfat: fix potential deadlock on __exfat_get_dentry_set
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: a3ff29a95f ("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>
2024-07-15 21:44:28 +09:00
Michael Jeanson
224821766f exfat: handle idmapped mounts
Pass the idmapped mount information to the different helper
functions. Adapt the uid/gid checks in exfat_setattr to use the
vfsuid/vfsgid helpers.

Based on the fat implementation in commit 4b78993681
("fat: handle idmapped mounts") by Christian Brauner.

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-07-15 21:44:28 +09:00
Eric Sandeen
ffe1b94d74 exfat: Convert to new uid/gid option parsing helpers
Convert to new uid/gid option parsing helpers

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Link: https://lore.kernel.org/r/dda575de-11a7-4139-8a25-07957d311ed3@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-07-02 06:21:18 +02:00
Yuezhang Mo
f19257997d exfat: zero the reserved fields of file and stream extension dentries
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 <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-04-25 21:59:59 +09:00
Yuezhang Mo
d7ed5232f0 exfat: fix timing of synchronizing bitmap and inode
Commit(f55c096f62 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: f55c096f62 ("exfat: do not zero the extended part")
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-31 23:39:29 +09:00
Linus Torvalds
1b3e251373 Merge tag 'exfat-for-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat
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
2024-03-21 09:47:12 -07:00
Yuezhang Mo
dc38fdc51b exfat: remove duplicate update parent dir
For renaming, the directory only needs to be updated once if it
is in the same directory.

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>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:56:10 +09:00
Yuezhang Mo
96cf51accc exfat: do not sync parent dir if just update timestamp
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 <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:56:05 +09:00
Yuezhang Mo
4d71455976 exfat: remove unused functions
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 <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:56:01 +09:00
Yuezhang Mo
af02c72d0b exfat: convert exfat_find_empty_entry() to use dentry cache
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 <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:55:54 +09:00
Yuezhang Mo
d97e060673 exfat: convert exfat_init_ext_entry() to use dentry cache
Before this conversion, in exfat_init_ext_entry(), to init
the dentries in a dentry set, the sync times is equals the
dentry number if 'dirsync' or 'sync' is enabled.
That affects not only performance but also device life.

After this conversion, only needs to be synchronized once if
'dirsync' or 'sync' is enabled.

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>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:55:49 +09:00
Yuezhang Mo
4e1aa22fea exfat: move free cluster out of exfat_init_ext_entry()
exfat_init_ext_entry() is an init function, it's a bit strange
to free cluster in it. And the argument 'inode' will be removed
from exfat_init_ext_entry(). So this commit changes to free the
cluster in exfat_remove_entries().

Code refinement, no functional changes.

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>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:55:45 +09:00
Yuezhang Mo
ff4343da02 exfat: convert exfat_remove_entries() to use dentry cache
Before this conversion, in exfat_remove_entries(), to mark the
dentries in a dentry set as deleted, the sync times is equals
the dentry numbers if 'dirsync' or 'sync' is enabled.
That affects not only performance but also device life.

After this conversion, only needs to be synchronized once if
'dirsync' or 'sync' is enabled.

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>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:55:40 +09:00
Yuezhang Mo
cf8663fa99 exfat: convert exfat_add_entry() to use dentry cache
After this conversion, if "dirsync" or "sync" is enabled, the
number of synchronized dentries in exfat_add_entry() will change
from 2 to 1.

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>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:55:36 +09:00
Yuezhang Mo
01da3a5176 exfat: add exfat_get_empty_dentry_set() helper
This helper is used to lookup empty dentry set. If there are
no enough empty dentries at the input location, this helper will
return the number of dentries that need to be skipped for the
next lookup.

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>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:55:33 +09:00
Yuezhang Mo
7b6bab2359 exfat: add __exfat_get_dentry_set() helper
Since exfat_get_dentry_set() invokes the validate functions of
exfat_validate_entry(), it only supports getting a directory
entry set of an existing file, doesn't support getting an empty
entry set.

To remove the limitation, add this helper.

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>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
2024-03-19 20:55:28 +09:00