syzbot reported a warning which could cause shift-out-of-bounds issue.
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x183/0x22e lib/dump_stack.c:120
ubsan_epilogue lib/ubsan.c:148 [inline]
__ubsan_handle_shift_out_of_bounds+0x432/0x4d0 lib/ubsan.c:395
exfat_read_boot_sector fs/exfat/super.c:471 [inline]
__exfat_fill_super fs/exfat/super.c:556 [inline]
exfat_fill_super+0x2acb/0x2d00 fs/exfat/super.c:624
get_tree_bdev+0x406/0x630 fs/super.c:1291
vfs_get_tree+0x86/0x270 fs/super.c:1496
do_new_mount fs/namespace.c:2881 [inline]
path_mount+0x1937/0x2c50 fs/namespace.c:3211
do_mount fs/namespace.c:3224 [inline]
__do_sys_mount fs/namespace.c:3432 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3409
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
exfat specification describe sect_per_clus_bits field of boot sector
could be at most 25 - sect_size_bits and at least 0. And sect_size_bits
can also affect this calculation, It also needs validation.
This patch add validation for sect_per_clus_bits and sect_size_bits
field of boot sector.
Fixes: 719c1e1829 ("exfat: add super block operations")
Cc: stable@vger.kernel.org # v5.9+
Reported-by: syzbot+da4fe66aaadd3c2e2d1c@syzkaller.appspotmail.com
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Pull misc vfs updates from Al Viro:
"Assorted stuff all over the place (the largest group here is
Christoph's stat cleanups)"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: remove KSTAT_QUERY_FLAGS
fs: remove vfs_stat_set_lookup_flags
fs: move vfs_fstatat out of line
fs: implement vfs_stat and vfs_lstat in terms of vfs_fstatat
fs: remove vfs_statx_fd
fs: omfs: use kmemdup() rather than kmalloc+memcpy
[PATCH] reduce boilerplate in fsid handling
fs: Remove duplicated flag O_NDELAY occurring twice in VALID_OPEN_FLAGS
selftests: mount: add nosymfollow tests
Add a "nosymfollow" mount option.
Remove 'rwoffset' in exfat_inode_info and replace it with the parameter of
exfat_readdir().
Since rwoffset is referenced only by exfat_readdir(), it is not necessary
a exfat_inode_info's member.
Also, change cpos to point to the next of entry-set, and return the index
of dir-entry via dir_entry->entry.
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Acked-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
MediaFailure and VolumeDirty should be retained if these are set before
mounting.
In '3.1.13.3 Media Failure Field' of exfat specification describe:
If, upon mounting a volume, the value of this field is 1,
implementations which scan the entire volume for media failures and
record all failures as "bad" clusters in the FAT (or otherwise resolve
media failures) may clear the value of this field to 0.
Therefore, We should not clear MediaFailure without scanning volume.
In '8.1 Recommended Write Ordering' of exfat specification describe:
Clear the value of the VolumeDirty field to 0, if its value prior to
the first step was 0.
Therefore, We should not clear VolumeDirty after mounting.
Also rename ERR_MEDIUM to MEDIA_FAILURE.
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
This flag is set/reset in exfat_put_super()/exfat_sync_fs()
to avoid sync_blockdev().
- exfat_put_super():
Before calling this, the VFS has already called sync_filesystem(),
so sync is never performed here.
- exfat_sync_fs():
After calling this, the VFS calls sync_blockdev(), so, it is meaningless
to check EXFAT_SB_DIRTY or to bypass sync_blockdev() here.
Remove the EXFAT_SB_DIRTY check to ensure synchronization.
And remove the code related to the flag.
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
We need to commit dirty metadata and pages to disk
before remounting exfat as read-only.
This fixes a failure in xfstests generic/452
generic/452 does the following:
cp something <exfat>/
mount -o remount,ro <exfat>
the <exfat>/something is corrupted. because while
exfat is remounted as read-only, exfat doesn't
have a chance to commit metadata and
vfs invalidates page caches in a block device.
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Acked-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Add Boot-Regions verification specified in exFAT specification.
Note that the checksum type is strongly related to the raw structure,
so the'u32 'type is used to clarify the number of bits.
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Separate the boot sector analysis to read_boot_sector().
And add a check for the fs_name field.
Furthermore, add a strict consistency check, because overlapping areas
can cause serious corruption.
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Aggregate PBR related definitions and redefine as "boot_sector" to comply
with the exFAT specification.
And, rename variable names including 'pbr'.
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
There is no need to init 'sync' in exfat_set_vol_flags().
This also fixes the following coccicheck warning:
fs/exfat/super.c:104:6-10: WARNING: Assignment of 0/1 to bool variable
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Remove the direct use of KERN_<LEVEL> in functions by creating
separate exfat_<level> macros.
Miscellanea:
o Remove several unnecessary terminating newlines in formats
o Realign arguments and fit to 80 columns where appropriate
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
As Ubuntu and Fedora release new version used kernel version equal to or
higher than v5.4, They started to support kernel exfat filesystem.
Linus reported a mount error with new version of exfat on Fedora:
exfat: Unknown parameter 'namecase'
This is because there is a difference in mount option between old
staging/exfat and new exfat. And utf8, debug, and codepage options as
well as namecase have been removed from new exfat.
This patch add the dummy mount options as deprecated option to be
backward compatible with old one.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The timestamp for access_time has double seconds granularity(There is no
10msIncrement field for access_time unlike create/modify_time).
exfat's atimes are restricted to only 2s granularity so after
we set an atime, round it down to the nearest 2s and set the
sub-second component of the timestamp to 0.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
The s_time_gran superblock field indicates the on-disk nanosecond
granularity of timestamps, and for exfat that seems to be 10ms, so
set s_time_gran to 10000000ns. Without this, in-memory timestamps
change when they get re-read from disk.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Unify access to boot sector via 'sbi->pbr_bh'.
This fixes vol_flags inconsistency at read failed in fs_set_vol_flags(),
and buffer_head leak in __exfat_fill_super().
Signed-off-by: Tetsuhiro Kohada <Kohada.Tetsuhiro@dc.MitsubishiElectric.co.jp>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
This adds the necessary MODULE_ALIAS_FS() to exfat so the module gets
automatically loaded when an exfat filesystem is mounted.
Signed-off-by: Thomas Backlund <tmb@mageia.org>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Discard support was always unconditionally disabled. Now it is disabled
only in the case when blk_queue_discard() returns false.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Al Viro recently reworked the way file system parameters are handled
Update super.c to work with it in linux-next 20200203.
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This adds the implementation of superblock operations for exfat.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Namjae Jeon