linux.git/drivers/mtd/ubi, branch v6.11

ubi: Fix ubi_init() ubiblock_exit() section mismatch

2024-07-28T18:08:25+00:00

Since ubiblock_exit() is now called from an init function,
the __exit section no longer makes sense.

Cc: Ben Hutchings 
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202407131403.wZJpd8n2-lkp@intel.com/
Signed-off-by: Richard Weinberger 
Reviewed-by: Zhihao Cheng

ubi: block: fix null-pointer-dereference in ubiblock_create()

2024-07-12T19:56:23+00:00

Similar to commit adbf4c4954e3 ("ubi: block: fix memleak in
ubiblock_create()"), 'dev->gd' is not assigned but dereferenced if
blk_mq_alloc_tag_set() fails, and leading to a null-pointer-dereference.
Fix it by using pr_err() and variable 'dev' to print error log.

Additionally, the log in the error handle path of idr_alloc() has
been improved by using pr_err(), too. Before initializing device
name, using dev_err() will print error log with 'null' instead of
the actual device name, like this:
  block (null): ...
        ~~~~~~
It is unclear. Using pr_err() can print more details of the device.
The improved log is:
  ubiblock0_0: ...

Fixes: 77567b25ab9f ("ubi: use blk_mq_alloc_disk and blk_cleanup_disk")
Reported-by: Dan Carpenter 
Signed-off-by: Li Nan 
Reviewed-by: Zhihao Cheng 
Reviewed-by: Daniel Golle 
Signed-off-by: Richard Weinberger

ubifs: correct UBIFS_DFS_DIR_LEN macro definition and improve code clarity

2024-07-12T19:52:24+00:00

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 
Reviewed-by: Zhihao Cheng 
Signed-off-by: Richard Weinberger

mtd: ubi: Restore missing cleanup on ubi_init() failure path

2024-07-12T19:43:09+00:00

We need to clean-up debugfs and ubiblock if we fail after initialising
them.

Signed-off-by: Ben Hutchings 
Fixes: 927c145208b0 ("mtd: ubi: attach from device tree")
Signed-off-by: Richard Weinberger

mtd: ubi: avoid expensive do_div() on 32-bit machines

2024-07-12T17:46:21+00:00

The use of do_div() in ubi_nvmem_reg_read() makes calling it on
32-bit machines rather expensive. Since the 'from' variable is
known to be a 32-bit quantity, it is clearly never needed and
can be optimized into a regular division operation.

Fixes: b8a77b9a5f9c ("mtd: ubi: fix NVMEM over UBI volumes on 32-bit systems")
Fixes: 3ce485803da1 ("mtd: ubi: provide NVMEM layer over UBI volumes")
Signed-off-by: Arnd Bergmann 
Reviewed-by: Zhihao Cheng 
Signed-off-by: Richard Weinberger

mtd: ubi: make ubi_class constant

2024-07-12T17:45:09+00:00

Since commit 43a7206b0963 ("driver core: class: make class_register() take
a const *"), the driver core allows for struct class to be in read-only
memory, so move the ubi_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at boot time.

Cc: Greg Kroah-Hartman 
Suggested-by: Greg Kroah-Hartman 
Signed-off-by: Ricardo B. Marliere 
Reviewed-by: Zhihao Cheng 
Reviewed-by: Miquel Raynal 
Signed-off-by: Richard Weinberger

ubi: eba: properly rollback inside self_check_eba

2024-07-12T17:42:46+00:00

In case of a memory allocation failure in the volumes loop we can only
process the already allocated scan_eba and fm_eba array elements on the
error path - others are still uninitialized.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 00abf3041590 ("UBI: Add self_check_eba()")
Cc: stable@vger.kernel.org
Signed-off-by: Fedor Pchelkin 
Reviewed-by: Zhihao Cheng 
Signed-off-by: Richard Weinberger

Merge tag 'ubifs-for-linus-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs

2024-03-21T22:09:29+00:00

Pull UBI and UBIFS updates from Richard Weinberger:
 "UBI:
   - Add Zhihao Cheng as reviewer
   - Attach via device tree
   - Add NVMEM layer
   - Various fastmap related fixes

  UBIFS:
   - Add Zhihao Cheng as reviewer
   - Convert to folios
   - Various fixes (memory leaks in error paths, function prototypes)"

* tag 'ubifs-for-linus-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs: (34 commits)
  mtd: ubi: fix NVMEM over UBI volumes on 32-bit systems
  mtd: ubi: provide NVMEM layer over UBI volumes
  mtd: ubi: populate ubi volume fwnode
  mtd: ubi: introduce pre-removal notification for UBI volumes
  mtd: ubi: attach from device tree
  mtd: ubi: block: use notifier to create ubiblock from parameter
  dt-bindings: mtd: ubi-volume: allow UBI volumes to provide NVMEM
  dt-bindings: mtd: add basic bindings for UBI
  ubifs: Queue up space reservation tasks if retrying many times
  ubifs: ubifs_symlink: Fix memleak of inode->i_link in error path
  ubifs: dbg_check_idx_size: Fix kmemleak if loading znode failed
  ubi: Correct the number of PEBs after a volume resize failure
  ubi: fix slab-out-of-bounds in ubi_eba_get_ldesc+0xfb/0x130
  ubi: correct the calculation of fastmap size
  ubifs: Remove unreachable code in dbg_check_ltab_lnum
  ubifs: fix function pointer cast warnings
  ubifs: fix sort function prototype
  ubi: Check for too small LEB size in VTBL code
  MAINTAINERS: Add Zhihao Cheng as UBI/UBIFS reviewer
  ubifs: Convert populate_page() to take a folio
  ...

mtd: ubi: fix NVMEM over UBI volumes on 32-bit systems

2024-03-10T21:14:28+00:00

A compiler warning related to sizeof(int) != 8 when calling do_div()
is triggered when building on 32-bit platforms.
Address this by using integer types having a well-defined size.

Fixes: 3ce485803da1 ("mtd: ubi: provide NVMEM layer over UBI volumes")
Signed-off-by: Daniel Golle 
Reviewed-by: Zhihao Cheng 
Tested-by: Randy Dunlap 
Signed-off-by: Richard Weinberger

mtd: ubi: provide NVMEM layer over UBI volumes

2024-02-25T21:42:23+00:00

In an ideal world we would like UBI to be used where ever possible on a
NAND chip. And with UBI support in ARM Trusted Firmware and U-Boot it
is possible to achieve an (almost-)all-UBI flash layout. Hence the need
for a way to also use UBI volumes to store board-level constants, such
as MAC addresses and calibration data of wireless interfaces.

Add UBI volume NVMEM driver module exposing UBI volumes as NVMEM
providers. Allow UBI devices to have a "volumes" firmware subnode with
volumes which may be compatible with "nvmem-cells".
Access to UBI volumes via the NVMEM interface at this point is
read-only, and it is slow, opening and closing the UBI volume for each
access due to limitations of the NVMEM provider API.

Signed-off-by: Daniel Golle 
Signed-off-by: Richard Weinberger