Commit Graph

6 Commits

Author SHA1 Message Date
ZhaoLong Wang
7037c96d8c ubifs: correct UBIFS_DFS_DIR_LEN macro definition and improve code clarity
The UBIFS_DFS_DIR_LEN macro, which defines the maximum length of the UBIFS
debugfs directory name, has an incorrect formula and misleading comments.
The current formula is (3 + 1 + 2*2 + 1), which assumes that both UBI device
number and volume ID are limited to 2 characters. However, UBI device number
ranges from 0 to 31 (2 characters), and volume ID ranges from 0 to 127 (up
to 3 characters).

Although the current code works due to the cancellation of mathematical
errors (9 + 1 = 10, which matches the correct UBIFS_DFS_DIR_LEN value), it
can lead to confusion and potential issues in the future.

This patch aims to improve the code clarity and maintainability by making
the following changes:

1. Corrects the UBIFS_DFS_DIR_LEN macro definition to (3 + 1 + 2 + 3 + 1),
   accommodating the maximum lengths of both UBI device number and volume ID,
   plus the separators and null terminator.
2. Updates the snprintf calls to use UBIFS_DFS_DIR_LEN instead of
   UBIFS_DFS_DIR_LEN + 1, removing the unnecessary +1.
3. Modifies the error checks to compare against UBIFS_DFS_DIR_LEN using >=
   instead of >, aligning with the corrected macro definition.
4. Removes the redundant +1 in the dfs_dir_name array definitions in ubi.h
   and debug.h.

While these changes do not affect the runtime behavior, they make the code
more readable, maintainable, and less prone to future errors.

v2->v3:

 - Removes the duplicated UBIFS_DFS_DIR_LEN and UBIFS_DFS_DIR_NAME macro
   definitions in ubifs.h, as they are already defined in debug.h.

Signed-off-by: ZhaoLong Wang <wangzhaolong1@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2024-07-12 21:52:24 +02:00
Thomas Weißschuh
22d74bc26b ubifs: make kobj_type structures constant
Since commit ee6d3dd4ed ("driver core: make kobj_type constant.")
the driver core allows the usage of const struct kobj_type.

Take advantage of this to constify the structure definitions to prevent
modification at runtime.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-13 22:29:54 +01:00
Liu Shixin
203a55f04f ubifs: Fix memory leak in ubifs_sysfs_init()
When insmod ubifs.ko, a kmemleak reported as below:

 unreferenced object 0xffff88817fb1a780 (size 8):
   comm "insmod", pid 25265, jiffies 4295239702 (age 100.130s)
   hex dump (first 8 bytes):
     75 62 69 66 73 00 ff ff                          ubifs...
   backtrace:
     [<ffffffff81b3fc4c>] slab_post_alloc_hook+0x9c/0x3c0
     [<ffffffff81b44bf3>] __kmalloc_track_caller+0x183/0x410
     [<ffffffff8198d3da>] kstrdup+0x3a/0x80
     [<ffffffff8198d486>] kstrdup_const+0x66/0x80
     [<ffffffff83989325>] kvasprintf_const+0x155/0x190
     [<ffffffff83bf55bb>] kobject_set_name_vargs+0x5b/0x150
     [<ffffffff83bf576b>] kobject_set_name+0xbb/0xf0
     [<ffffffff8100204c>] do_one_initcall+0x14c/0x5a0
     [<ffffffff8157e380>] do_init_module+0x1f0/0x660
     [<ffffffff815857be>] load_module+0x6d7e/0x7590
     [<ffffffff8158644f>] __do_sys_finit_module+0x19f/0x230
     [<ffffffff815866b3>] __x64_sys_finit_module+0x73/0xb0
     [<ffffffff88c98e85>] do_syscall_64+0x35/0x80
     [<ffffffff88e00087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

When kset_register() failed, we should call kset_put to cleanup it.

Fixes: 2e3cbf4258 ("ubifs: Export filesystem error counters")
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:35 +01:00
Greg Kroah-Hartman
c6479f19e2 ubifs: use default_groups in kobj_type
There are currently 2 ways to create a set of sysfs files for a
kobj_type, through the default_attrs field, and the default_groups
field.  Move the ubifs sysfs code to use default_groups field which has
been the preferred way since aa30f47cf6 ("kobject: Add support for
default attribute groups to kobj_type") so that we can soon get rid of
the obsolete default_attrs field.

Cc: Stefan Schaeckeler <schaecsn@gmx.net>
Cc: linux-mtd@lists.infradead.org
Acked-by: Richard Weinberger <richard@nod.at>
Link: https://lore.kernel.org/r/20220114104820.1340879-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 15:57:19 +01:00
Dan Carpenter
d3de970bcb ubifs: fix snprintf() length check
The snprintf() function returns the number of bytes (not including the
NUL terminator) which would have been printed if there were enough
space.  So it can be greater than UBIFS_DFS_DIR_LEN.  And actually if
it equals UBIFS_DFS_DIR_LEN then that's okay so this check is too
strict.

Fixes: 9a620291fc01 ("ubifs: Export filesystem error counters")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-23 22:08:19 +01:00
Stefan Schaeckeler
2e3cbf4258 ubifs: Export filesystem error counters
Not all ubifs filesystem errors are propagated to userspace.

Export bad magic, bad node and crc errors via sysfs. This allows userspace
to notice filesystem errors:

 /sys/fs/ubifs/ubiX_Y/errors_magic
 /sys/fs/ubifs/ubiX_Y/errors_node
 /sys/fs/ubifs/ubiX_Y/errors_crc

The counters are reset to 0 with a remount.

Signed-off-by: Stefan Schaeckeler <sschaeck@cisco.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-23 20:23:42 +01:00