Commit graph

818 commits

Author SHA1 Message Date
Christoph Hellwig
05bdb99653 block: replace fmode_t with a block-specific type for block open flags
The only overlap between the block open flags mapped into the fmode_t and
other uses of fmode_t are FMODE_READ and FMODE_WRITE.  Define a new
blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and
->ioctl and stop abusing fmode_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jack Wang <jinpu.wang@ionos.com>		[rnbd]
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-12 08:04:05 -06:00
Christoph Hellwig
ae220766d8 block: remove the unused mode argument to ->release
The mode argument to the ->release block_device_operation is never used,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com>			[rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-12 08:04:04 -06:00
Christoph Hellwig
d32e2bf837 block: pass a gendisk to ->open
->open is only called on the whole device.  Make that explicit by
passing a gendisk instead of the block_device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com>		[rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-12 08:04:04 -06:00
Linus Torvalds
9f2692326b This pull request contains updates for UBI and UBIFS
UBI:
 	- Fix error value for try_write_vid_and_data()
 	- Minor cleanups
 
 UBIFS:
 	- Fixes for various memory leaks
 	- Minor cleanups
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Merge tag 'ubifs-for-linus-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs

Pull UBI and UBIFS updates from Richard Weinberger:
 "UBI:

   - Fix error value for try_write_vid_and_data()

   - Minor cleanups

  UBIFS:

   - Fixes for various memory leaks

   - Minor cleanups"

* tag 'ubifs-for-linus-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubifs: Fix memleak when insert_old_idx() failed
  Revert "ubifs: dirty_cow_znode: Fix memleak in error handling path"
  ubifs: Fix memory leak in do_rename
  ubifs: Free memory for tmpfile name
  ubi: Fix return value overwrite issue in try_write_vid_and_data()
  ubifs: Remove return in compr_exit()
  ubi: Simplify bool conversion
2023-05-03 18:58:59 -07:00
Linus Torvalds
556eb8b791 Driver core changes for 6.4-rc1
Here is the large set of driver core changes for 6.4-rc1.
 
 Once again, a busy development cycle, with lots of changes happening in
 the driver core in the quest to be able to move "struct bus" and "struct
 class" into read-only memory, a task now complete with these changes.
 
 This will make the future rust interactions with the driver core more
 "provably correct" as well as providing more obvious lifetime rules for
 all busses and classes in the kernel.
 
 The changes required for this did touch many individual classes and
 busses as many callbacks were changed to take const * parameters
 instead.  All of these changes have been submitted to the various
 subsystem maintainers, giving them plenty of time to review, and most of
 them actually did so.
 
 Other than those changes, included in here are a small set of other
 things:
   - kobject logging improvements
   - cacheinfo improvements and updates
   - obligatory fw_devlink updates and fixes
   - documentation updates
   - device property cleanups and const * changes
   - firwmare loader dependency fixes.
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the large set of driver core changes for 6.4-rc1.

  Once again, a busy development cycle, with lots of changes happening
  in the driver core in the quest to be able to move "struct bus" and
  "struct class" into read-only memory, a task now complete with these
  changes.

  This will make the future rust interactions with the driver core more
  "provably correct" as well as providing more obvious lifetime rules
  for all busses and classes in the kernel.

  The changes required for this did touch many individual classes and
  busses as many callbacks were changed to take const * parameters
  instead. All of these changes have been submitted to the various
  subsystem maintainers, giving them plenty of time to review, and most
  of them actually did so.

  Other than those changes, included in here are a small set of other
  things:

   - kobject logging improvements

   - cacheinfo improvements and updates

   - obligatory fw_devlink updates and fixes

   - documentation updates

   - device property cleanups and const * changes

   - firwmare loader dependency fixes.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits)
  device property: make device_property functions take const device *
  driver core: update comments in device_rename()
  driver core: Don't require dynamic_debug for initcall_debug probe timing
  firmware_loader: rework crypto dependencies
  firmware_loader: Strip off \n from customized path
  zram: fix up permission for the hot_add sysfs file
  cacheinfo: Add use_arch[|_cache]_info field/function
  arch_topology: Remove early cacheinfo error message if -ENOENT
  cacheinfo: Check cache properties are present in DT
  cacheinfo: Check sib_leaf in cache_leaves_are_shared()
  cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
  cacheinfo: Add arm64 early level initializer implementation
  cacheinfo: Add arch specific early level initializer
  tty: make tty_class a static const structure
  driver core: class: remove struct class_interface * from callbacks
  driver core: class: mark the struct class in struct class_interface constant
  driver core: class: make class_register() take a const *
  driver core: class: mark class_release() as taking a const *
  driver core: remove incorrect comment for device_create*
  MIPS: vpe-cmp: remove module owner pointer from struct class usage.
  ...
2023-04-27 11:53:57 -07:00
Wang YanQing
31a149d5c1 ubi: Fix return value overwrite issue in try_write_vid_and_data()
The commit 2d78aee426 ("UBI: simplify LEB write and atomic LEB change code")
adds helper function, try_write_vid_and_data(), to simplify the code, but this
helper function has bug, it will return 0 (success) when ubi_io_write_vid_hdr()
or the ubi_io_write_data() return error number (-EIO, etc), because the return
value of ubi_wl_put_peb() will overwrite the original return value.

This issue will cause unexpected data loss issue, because the caller of this
function and UBIFS willn't know the data is lost.

Fixes: 2d78aee426 ("UBI: simplify LEB write and atomic LEB change code")
Cc: stable@vger.kernel.org
Signed-off-by: Wang YanQing <udknight@gmail.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-04-21 22:31:15 +02:00
Yang Li
ef5031137b ubi: Simplify bool conversion
./drivers/mtd/ubi/build.c:1261:33-38: WARNING: conversion to bool not needed here

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=4061
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-04-21 21:44:46 +02:00
Linus Torvalds
bc88aa51a6 This pull request contains the following bug fixes for UBI and UBIFS:
- Fix for a stable patch: Fix failure attaching when vid_hdr offset equals to (sub)page size
 - Fix for a deadlock in UBI's worker thread
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Merge tag 'ubifs-for-linus-6.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs

Pull UBI fixes from Richard Weinberger:

 - Fix failure to attach when vid_hdr offset equals the (sub)page size

 - Fix for a deadlock in UBI's worker thread

* tag 'ubifs-for-linus-6.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubi: Fix failure attaching when vid_hdr offset equals to (sub)page size
  ubi: Fix deadlock caused by recursively holding work_sem
2023-04-15 16:55:09 -07:00
Greg Kroah-Hartman
cd8fe5b6db Merge 6.3-rc5 into driver-core-next
We need the fixes in here for testing, as well as the driver core
changes for documentation updates to build on.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-03 09:33:30 +02:00
Zhihao Cheng
1e020e1b96 ubi: Fix failure attaching when vid_hdr offset equals to (sub)page size
Following process will make ubi attaching failed since commit
1b42b1a36f ("ubi: ensure that VID header offset ... size"):

ID="0xec,0xa1,0x00,0x15" # 128M 128KB 2KB
modprobe nandsim id_bytes=$ID
flash_eraseall /dev/mtd0
modprobe ubi mtd="0,2048"  # set vid_hdr offset as 2048 (one page)
(dmesg):
  ubi0 error: ubi_attach_mtd_dev [ubi]: VID header offset 2048 too large.
  UBI error: cannot attach mtd0
  UBI error: cannot initialize UBI, error -22

Rework original solution, the key point is making sure
'vid_hdr_shift + UBI_VID_HDR_SIZE < ubi->vid_hdr_alsize',
so we should check vid_hdr_shift rather not vid_hdr_offset.
Then, ubi still support (sub)page aligined VID header offset.

Fixes: 1b42b1a36f ("ubi: ensure that VID header offset ... size")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Tested-by: Nicolas Schichan <nschichan@freebox.fr>
Tested-by: Miquel Raynal <miquel.raynal@bootlin.com> # v5.10, v4.19
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-03-29 23:32:57 +02:00
Greg Kroah-Hartman
75a2d4226b driver core: class: mark the struct class for sysfs callbacks as constant
struct class should never be modified in a sysfs callback as there is
nothing in the structure to modify, and frankly, the structure is almost
never used in a sysfs callback, so mark it as constant to allow struct
class to be moved to read-only memory.

While we are touching all class sysfs callbacks also mark the attribute
as constant as it can not be modified.  The bonding code still uses this
structure so it can not be removed from the function callbacks.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Russ Weight <russell.h.weight@intel.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Steve French <sfrench@samba.org>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: linux-cifs@vger.kernel.org
Cc: linux-gpio@vger.kernel.org
Cc: linux-mtd@lists.infradead.org
Cc: linux-rdma@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: netdev@vger.kernel.org
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20230325084537.3622280-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-29 07:54:58 +02:00
Greg Kroah-Hartman
10a03c36b7 drivers: remove struct module * setting from struct class
There is no need to manually set the owner of a struct class, as the
registering function does it automatically, so remove all of the
explicit settings from various drivers that did so as it is unneeded.

This allows us to remove this pointer entirely from this structure going
forward.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230313181843.1207845-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17 15:16:27 +01:00
Richard Weinberger
e25c54d179 ubi: block: Fix missing blk_mq_end_request
Switching to BLK_MQ_F_BLOCKING wrongly removed the call to
blk_mq_end_request(). Add it back to have our IOs finished

Fixes: 91cc8fbcc8 ("ubi: block: set BLK_MQ_F_BLOCKING")
Analyzed-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Daniel Palmer <daniel@0x0f.com>
Link: https://lore.kernel.org/linux-mtd/CAHk-=wi29bbBNh3RqJKu3PxzpjDN5D5K17gEVtXrb7-6bfrnMQ@mail.gmail.com/
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Daniel Palmer <daniel@0x0f.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-03-11 09:00:25 -08:00
ZhaoLong Wang
f773f0a331 ubi: Fix deadlock caused by recursively holding work_sem
During the processing of the bgt, if the sync_erase() return -EBUSY
or some other error code in __erase_worker(),schedule_erase() called
again lead to the down_read(ubi->work_sem) hold twice and may get
block by down_write(ubi->work_sem) in ubi_update_fastmap(),
which cause deadlock.

          ubi bgt                        other task
 do_work
  down_read(&ubi->work_sem)          ubi_update_fastmap
  erase_worker                         # Blocked by down_read
   __erase_worker                      down_write(&ubi->work_sem)
    schedule_erase
     schedule_ubi_work
      down_read(&ubi->work_sem)

Fix this by changing input parameter @nested of the schedule_erase() to
'true' to avoid recursively acquiring the down_read(&ubi->work_sem).

Also, fix the incorrect comment about @nested parameter of the
schedule_erase() because when down_write(ubi->work_sem) is held, the
@nested is also need be true.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217093
Fixes: 2e8f08deab ("ubi: Fix races around ubi_refill_pools()")
Signed-off-by: ZhaoLong Wang <wangzhaolong1@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-03-04 17:59:12 +01:00
Harshit Mogalapalli
8fcf2d012c ubi: block: Fix a possible use-after-free bug in ubiblock_create()
Smatch warns:
	drivers/mtd/ubi/block.c:438 ubiblock_create()
	warn: '&dev->list' not removed from list

'dev' is freed in 'out_free_dev:, but it is still on the list.

To fix this, delete the list item before freeing.

Fixes: 91cc8fbcc8 ("ubi: block: set BLK_MQ_F_BLOCKING")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-14 15:17:55 +01:00
Daniel Golle
05b8773ca3 mtd: ubi: block: wire-up device parent
ubiblock devices were previously only identifyable by their name, but
not connected to their parent UBI volume device e.g. in sysfs.
Properly parent ubiblock device as descendant of a UBI volume device
to reflect device model hierachy.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-13 22:24:10 +01:00
Daniel Golle
1ecf9e3904 mtd: ubi: wire-up parent MTD device
Wire up the device parent pointer of UBI devices to their lower MTD
device, typically an MTD partition or whole-chip device.

The most noticeable change is that in sysfs, previously ubi devices
would be could in /sys/devices/virtual/ubi while after this change they
would be correctly attached to their parent MTD device, e.g.

/sys/devices/platform/1100d000.spi/spi_master/spi1/spi1.0/mtd/mtd2/ubi0.

Locating UBI devices using /sys/class/ubi/ of course still works as
well.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-13 22:23:03 +01:00
Randy Dunlap
0b3bc49c93 ubi: use correct names in function kernel-doc comments
Fix kernel-doc warnings by using the correct function names in
their kernel-doc notation:

drivers/mtd/ubi/eba.c:72: warning: expecting prototype for next_sqnum(). Prototype was for ubi_next_sqnum() instead
drivers/mtd/ubi/wl.c:176: warning: expecting prototype for wl_tree_destroy(). Prototype was for wl_entry_destroy() instead
drivers/mtd/ubi/misc.c:24: warning: expecting prototype for calc_data_len(). Prototype was for ubi_calc_data_len() instead

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-05 22:36:39 +01:00
Christoph Hellwig
91cc8fbcc8 ubi: block: set BLK_MQ_F_BLOCKING
Set BLK_MQ_F_BLOCKING so that the block layer always calls ->queue_rq
from process context and drop the driver internal workqueue.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-05 22:36:12 +01:00
Jiapeng Chong
b5dd034f8f UBI: Fastmap: Fix kernel-doc
drivers/mtd/ubi/fastmap.c:104: warning: expecting prototype for new_fm_vhdr(). Prototype was for new_fm_vbuf() instead.

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2289
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:51 +01:00
Zhihao Cheng
4d57a7333e ubi: ubi_wl_put_peb: Fix infinite loop when wear-leveling work failed
Following process will trigger an infinite loop in ubi_wl_put_peb():

	ubifs_bgt		ubi_bgt
ubifs_leb_unmap
  ubi_leb_unmap
    ubi_eba_unmap_leb
      ubi_wl_put_peb	wear_leveling_worker
                          e1 = rb_entry(rb_first(&ubi->used)
			  e2 = get_peb_for_wl(ubi)
			  ubi_io_read_vid_hdr  // return err (flash fault)
			  out_error:
			    ubi->move_from = ubi->move_to = NULL
			    wl_entry_destroy(ubi, e1)
			      ubi->lookuptbl[e->pnum] = NULL
      retry:
        e = ubi->lookuptbl[pnum];	// return NULL
	if (e == ubi->move_from) {	// NULL == NULL gets true
	  goto retry;			// infinite loop !!!

$ top
  PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     COMMAND
  7676 root     20   0       0      0      0 R 100.0  0.0  ubifs_bgt0_0

Fix it by:
 1) Letting ubi_wl_put_peb() returns directly if wearl leveling entry has
    been removed from 'ubi->lookuptbl'.
 2) Using 'ubi->wl_lock' protecting wl entry deletion to preventing an
    use-after-free problem for wl entry in ubi_wl_put_peb().

Fetch a reproducer in [Link].

Fixes: 43f9b25a9c ("UBI: bugfix: protect from volume removal")
Fixes: ee59ba8b06 ("UBI: Fix stale pointers in ubi->lookuptbl")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216111
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:50 +01:00
Zhihao Cheng
a240bc5c43 ubi: Fix UAF wear-leveling entry in eraseblk_count_seq_show()
Wear-leveling entry could be freed in error path, which may be accessed
again in eraseblk_count_seq_show(), for example:

__erase_worker                eraseblk_count_seq_show
                                wl = ubi->lookuptbl[*block_number]
				if (wl)
  wl_entry_destroy
    ubi->lookuptbl[e->pnum] = NULL
    kmem_cache_free(ubi_wl_entry_slab, e)
		                   erase_count = wl->ec  // UAF!

Wear-leveling entry updating/accessing in ubi->lookuptbl should be
protected by ubi->wl_lock, fix it by adding ubi->wl_lock to serialize
wl entry accessing between wl_entry_destroy() and
eraseblk_count_seq_show().

Fetch a reproducer in [Link].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216305
Fixes: 7bccd12d27 ("ubi: Add debugfs file for tracking PEB state")
Fixes: 801c135ce7 ("UBI: Unsorted Block Images")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:50 +01:00
Zhihao Cheng
76f9476ece ubi: fastmap: Fix missed fm_anchor PEB in wear-leveling after disabling fastmap
After disabling fastmap(ubi->fm_disabled = 1), fastmap won't be updated,
fm_anchor PEB is missed being scheduled for erasing. Besides, fm_anchor
PEB may have smallest erase count, it doesn't participate wear-leveling.
The difference of erase count between fm_anchor PEB and other PEBs will
be larger and larger later on.

In which situation fastmap can be disabled? Initially, we have an UBI
image with fastmap. Then the image will be atttached without module
parameter 'fm_autoconvert', ubi turns to full scanning mode in one
random attaching process(eg. bad fastmap caused by powercut), ubi
fastmap is disabled since then.

Fix it by not getting fm_anchor if fastmap is disabled in
ubi_refill_pools().

Fetch a reproducer in [Link].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216341
Fixes: 4b68bf9a69 ("ubi: Select fastmap anchor PEBs considering ...")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:49 +01:00
ZhaoLong Wang
2de203d8ab ubi: Fix permission display of the debugfs files
Some interface files in debugfs support the read method
dfs_file_read(), but their rwx permissions is shown as
unreadable.

In the user mode, the following problem can be clearly seen:

 # ls -l /sys/kernel/debug/ubi/ubi0/
 total 0
 --w------- 1 root root 0 Oct 22 16:26 chk_fastmap
 --w------- 1 root root 0 Oct 22 16:26 chk_gen
 --w------- 1 root root 0 Oct 22 16:26 chk_io
 -r-------- 1 root root 0 Oct 22 16:26 detailed_erase_block_info
 --w------- 1 root root 0 Oct 22 16:26 tst_disable_bgt
 --w------- 1 root root 0 Oct 22 16:26 tst_emulate_bitflips
 --w------- 1 root root 0 Oct 22 16:26 tst_emulate_io_failures
 --w------- 1 root root 0 Oct 22 16:26 tst_emulate_power_cut
 --w------- 1 root root 0 Oct 22 16:26 tst_emulate_power_cut_max
 --w------- 1 root root 0 Oct 22 16:26 tst_emulate_power_cut_min

It shows that these files do not have read permission 'r',
but we can actually read their contents.

 # echo 1 > /sys/kernel/debug/ubi/ubi0/chk_io
 # cat /sys/kernel/debug/ubi/ubi0/chk_io
 1

User's permission access is determined by capabilities.
Of course, the root user is not restricted from reading
these files.

When reading a debugfs file, the process is as follows:

 ksys_read()
   vfs_read()
     if (file->f_op->read)
       file->f_op->read()
         full_proxy_open()
           real_fops->read()
             dfs_file_read() -- Read method of debugfs file.
     else if (file->f_op->read_iter)
       new_sync_read()
     else
       ret = -EINVAL -- Return -EINVAL if no read method.

This indicates that the debugfs file can be read as long as the read
method of the debugfs file is registered. This patch adds the read
permission display for file that support the read method.

Signed-off-by: ZhaoLong Wang <wangzhaolong1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:45 +01:00
Yang Yingliang
c15859bfd3 ubi: Fix possible null-ptr-deref in ubi_free_volume()
It willl cause null-ptr-deref in the following case:

uif_init()
  ubi_add_volume()
    cdev_add() -> if it fails, call kill_volumes()
    device_register()

kill_volumes() -> if ubi_add_volume() fails call this function
  ubi_free_volume()
    cdev_del()
    device_unregister() -> trying to delete a not added device,
			   it causes null-ptr-deref

So in ubi_free_volume(), it delete devices whether they are added
or not, it will causes null-ptr-deref.

Handle the error case whlie calling ubi_add_volume() to fix this
problem. If add volume fails, set the corresponding vol to null,
so it can not be accessed in kill_volumes() and release the
resource in ubi_add_volume() error path.

Fixes: 801c135ce7 ("UBI: Unsorted Block Images")
Suggested-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:44 +01:00
ZhaoLong Wang
7af73882dd ubi: fastmap: Add fastmap control support for module parameter
The UBI driver can use the IOCTL to disable the fastmap after the
mainline 669d204469 ("ubi: fastmap: Add fastmap control support
for 'UBI_IOCATT' ioctl"). To destroy the fastmap on a old image,
we need to reattach the device in user space.

However, if the UBI driver build in kernel and the UBI volume is
the root partition, the UBI device cannot be reattached in user
space. To disable fastmap in this case, the UBI must provide the
kernel cmdline parameters to disable fastmap during attach.

This patch add 'enable_fm' as 5th module init parameter of mtd=xx to
control fastmap enable or not. When the value is 0, fastmap will not
create and existed fastmap will destroyed for the given ubi device.
Default value is 0.

To enable or disable fastmap during module loading, fm_autoconvert
must be set to non-zero.

+-----------------+---------------+---------------------------+
|        \        |  enable_fm=0  |  enable_fm=1              |
+-----------------+---------------+---------------------------+
|fm_autoconvert=Y |  disable fm   |  enable fm                |
+---------------------------------+---------------------------+
|fm_autoconvert=N |  disable fm   | Enable fastmap if fastmap |
|                 |               | exists on the old image   |
+-------------------------------------------------------------+

Example:
  # - Attach mtd1 to ubi1, disable fastmap, mtd2 to ubi2, enable
      fastmap.
  # modprobe ubi mtd=1,0,0,1,0 mtd=2,0,0,2,1 fm_autoconvert=1

  # - If 5th parameter is not specified, the value is 0, fastmap is
      disable
  # modprobe ubi mtd=1 fm_autoconvert=1

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216623
Signed-off-by: ZhaoLong Wang <wangzhaolong1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:43 +01:00
Li Zetao
1e591ea072 ubi: Fix unreferenced object reported by kmemleak in ubi_resize_volume()
There is a memory leaks problem reported by kmemleak:

unreferenced object 0xffff888102007a00 (size 128):
  comm "ubirsvol", pid 32090, jiffies 4298464136 (age 2361.231s)
  hex dump (first 32 bytes):
ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
  backtrace:
[<ffffffff8176cecd>] __kmalloc+0x4d/0x150
[<ffffffffa02a9a36>] ubi_eba_create_table+0x76/0x170 [ubi]
[<ffffffffa029764e>] ubi_resize_volume+0x1be/0xbc0 [ubi]
[<ffffffffa02a3321>] ubi_cdev_ioctl+0x701/0x1850 [ubi]
[<ffffffff81975d2d>] __x64_sys_ioctl+0x11d/0x170
[<ffffffff83c142a5>] do_syscall_64+0x35/0x80
[<ffffffff83e0006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

This is due to a mismatch between create and destroy interfaces, and
in detail that "new_eba_tbl" created by ubi_eba_create_table() but
destroyed by kfree(), while will causing "new_eba_tbl->entries" not
freed.

Fix it by replacing kfree(new_eba_tbl) with
ubi_eba_destroy_table(new_eba_tbl)

Fixes: 799dca34ac ("UBI: hide EBA internals")
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:42 +01:00
Li Zetao
9af31d6ec1 ubi: Fix use-after-free when volume resizing failed
There is an use-after-free problem reported by KASAN:
  ==================================================================
  BUG: KASAN: use-after-free in ubi_eba_copy_table+0x11f/0x1c0 [ubi]
  Read of size 8 at addr ffff888101eec008 by task ubirsvol/4735

  CPU: 2 PID: 4735 Comm: ubirsvol
  Not tainted 6.1.0-rc1-00003-g84fa3304a7fc-dirty #14
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
  BIOS 1.14.0-1.fc33 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x34/0x44
   print_report+0x171/0x472
   kasan_report+0xad/0x130
   ubi_eba_copy_table+0x11f/0x1c0 [ubi]
   ubi_resize_volume+0x4f9/0xbc0 [ubi]
   ubi_cdev_ioctl+0x701/0x1850 [ubi]
   __x64_sys_ioctl+0x11d/0x170
   do_syscall_64+0x35/0x80
   entry_SYSCALL_64_after_hwframe+0x46/0xb0
   </TASK>

When ubi_change_vtbl_record() returns an error in ubi_resize_volume(),
"new_eba_tbl" will be freed on error handing path, but it is holded
by "vol->eba_tbl" in ubi_eba_replace_table(). It means that the liftcycle
of "vol->eba_tbl" and "vol" are different, so when resizing volume in
next time, it causing an use-after-free fault.

Fix it by not freeing "new_eba_tbl" after it replaced in
ubi_eba_replace_table(), while will be freed in next volume resizing.

Fixes: 801c135ce7 ("UBI: Unsorted Block Images")
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:41 +01:00
Mårten Lindahl
6addbe91fc ubi: block: Reduce warning print to info for static volumes
If volume size is not multiple of the sector size 512 a warning is
printed saying that the last non-sector aligned bytes will be ignored.

This should be valid for resizable volumes, but when creating static
volumes which are read only this will always be printed even if the
unaligned data is deliberate.

The message is still valid but the severity should be lowered for static
volumes.

Signed-off-by: Mårten Lindahl <marten.lindahl@axis.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:35 +01:00
George Kennedy
1b42b1a36f ubi: ensure that VID header offset + VID header size <= alloc, size
Ensure that the VID header offset + VID header size does not exceed
the allocated area to avoid slab OOB.

BUG: KASAN: slab-out-of-bounds in crc32_body lib/crc32.c:111 [inline]
BUG: KASAN: slab-out-of-bounds in crc32_le_generic lib/crc32.c:179 [inline]
BUG: KASAN: slab-out-of-bounds in crc32_le_base+0x58c/0x626 lib/crc32.c:197
Read of size 4 at addr ffff88802bb36f00 by task syz-executor136/1555

CPU: 2 PID: 1555 Comm: syz-executor136 Tainted: G        W
6.0.0-1868 #1
Hardware name: Red Hat KVM, BIOS 1.13.0-2.module+el8.3.0+7860+a7792d29
04/01/2014
Call Trace:
  <TASK>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x85/0xad lib/dump_stack.c:106
  print_address_description mm/kasan/report.c:317 [inline]
  print_report.cold.13+0xb6/0x6bb mm/kasan/report.c:433
  kasan_report+0xa7/0x11b mm/kasan/report.c:495
  crc32_body lib/crc32.c:111 [inline]
  crc32_le_generic lib/crc32.c:179 [inline]
  crc32_le_base+0x58c/0x626 lib/crc32.c:197
  ubi_io_write_vid_hdr+0x1b7/0x472 drivers/mtd/ubi/io.c:1067
  create_vtbl+0x4d5/0x9c4 drivers/mtd/ubi/vtbl.c:317
  create_empty_lvol drivers/mtd/ubi/vtbl.c:500 [inline]
  ubi_read_volume_table+0x67b/0x288a drivers/mtd/ubi/vtbl.c:812
  ubi_attach+0xf34/0x1603 drivers/mtd/ubi/attach.c:1601
  ubi_attach_mtd_dev+0x6f3/0x185e drivers/mtd/ubi/build.c:965
  ctrl_cdev_ioctl+0x2db/0x347 drivers/mtd/ubi/cdev.c:1043
  vfs_ioctl fs/ioctl.c:51 [inline]
  __do_sys_ioctl fs/ioctl.c:870 [inline]
  __se_sys_ioctl fs/ioctl.c:856 [inline]
  __x64_sys_ioctl+0x193/0x213 fs/ioctl.c:856
  do_syscall_x64 arch/x86/entry/common.c:50 [inline]
  do_syscall_64+0x3e/0x86 arch/x86/entry/common.c:80
  entry_SYSCALL_64_after_hwframe+0x63/0x0
RIP: 0033:0x7f96d5cf753d
Code:
RSP: 002b:00007fffd72206f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f96d5cf753d
RDX: 0000000020000080 RSI: 0000000040186f40 RDI: 0000000000000003
RBP: 0000000000400cd0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400be0
R13: 00007fffd72207e0 R14: 0000000000000000 R15: 0000000000000000
  </TASK>

Allocated by task 1555:
  kasan_save_stack+0x20/0x3d mm/kasan/common.c:38
  kasan_set_track mm/kasan/common.c:45 [inline]
  set_alloc_info mm/kasan/common.c:437 [inline]
  ____kasan_kmalloc mm/kasan/common.c:516 [inline]
  __kasan_kmalloc+0x88/0xa3 mm/kasan/common.c:525
  kasan_kmalloc include/linux/kasan.h:234 [inline]
  __kmalloc+0x138/0x257 mm/slub.c:4429
  kmalloc include/linux/slab.h:605 [inline]
  ubi_alloc_vid_buf drivers/mtd/ubi/ubi.h:1093 [inline]
  create_vtbl+0xcc/0x9c4 drivers/mtd/ubi/vtbl.c:295
  create_empty_lvol drivers/mtd/ubi/vtbl.c:500 [inline]
  ubi_read_volume_table+0x67b/0x288a drivers/mtd/ubi/vtbl.c:812
  ubi_attach+0xf34/0x1603 drivers/mtd/ubi/attach.c:1601
  ubi_attach_mtd_dev+0x6f3/0x185e drivers/mtd/ubi/build.c:965
  ctrl_cdev_ioctl+0x2db/0x347 drivers/mtd/ubi/cdev.c:1043
  vfs_ioctl fs/ioctl.c:51 [inline]
  __do_sys_ioctl fs/ioctl.c:870 [inline]
  __se_sys_ioctl fs/ioctl.c:856 [inline]
  __x64_sys_ioctl+0x193/0x213 fs/ioctl.c:856
  do_syscall_x64 arch/x86/entry/common.c:50 [inline]
  do_syscall_64+0x3e/0x86 arch/x86/entry/common.c:80
  entry_SYSCALL_64_after_hwframe+0x63/0x0

The buggy address belongs to the object at ffff88802bb36e00
  which belongs to the cache kmalloc-256 of size 256
The buggy address is located 0 bytes to the right of
  256-byte region [ffff88802bb36e00, ffff88802bb36f00)

The buggy address belongs to the physical page:
page:00000000ea4d1263 refcount:1 mapcount:0 mapping:0000000000000000
index:0x0 pfn:0x2bb36
head:00000000ea4d1263 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfffffc0010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff)
raw: 000fffffc0010200 ffffea000066c300 dead000000000003 ffff888100042b40
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
  ffff88802bb36e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff88802bb36e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88802bb36f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                    ^
  ffff88802bb36f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  ffff88802bb37000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Fixes: 801c135ce7 ("UBI: Unsorted Block Images")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-02 21:13:33 +01:00
Jason A. Donenfeld
8032bf1233 treewide: use get_random_u32_below() instead of deprecated function
This is a simple mechanical transformation done by:

@@
expression E;
@@
- prandom_u32_max
+ get_random_u32_below
  (E)

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Reviewed-by: SeongJae Park <sj@kernel.org> # for damon
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> # for arm
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-11-18 02:15:15 +01:00
Linus Torvalds
f1947d7c8a Random number generator fixes for Linux 6.1-rc1.
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Merge tag 'random-6.1-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random

Pull more random number generator updates from Jason Donenfeld:
 "This time with some large scale treewide cleanups.

  The intent of this pull is to clean up the way callers fetch random
  integers. The current rules for doing this right are:

   - If you want a secure or an insecure random u64, use get_random_u64()

   - If you want a secure or an insecure random u32, use get_random_u32()

     The old function prandom_u32() has been deprecated for a while
     now and is just a wrapper around get_random_u32(). Same for
     get_random_int().

   - If you want a secure or an insecure random u16, use get_random_u16()

   - If you want a secure or an insecure random u8, use get_random_u8()

   - If you want secure or insecure random bytes, use get_random_bytes().

     The old function prandom_bytes() has been deprecated for a while
     now and has long been a wrapper around get_random_bytes()

   - If you want a non-uniform random u32, u16, or u8 bounded by a
     certain open interval maximum, use prandom_u32_max()

     I say "non-uniform", because it doesn't do any rejection sampling
     or divisions. Hence, it stays within the prandom_*() namespace, not
     the get_random_*() namespace.

     I'm currently investigating a "uniform" function for 6.2. We'll see
     what comes of that.

  By applying these rules uniformly, we get several benefits:

   - By using prandom_u32_max() with an upper-bound that the compiler
     can prove at compile-time is ≤65536 or ≤256, internally
     get_random_u16() or get_random_u8() is used, which wastes fewer
     batched random bytes, and hence has higher throughput.

   - By using prandom_u32_max() instead of %, when the upper-bound is
     not a constant, division is still avoided, because
     prandom_u32_max() uses a faster multiplication-based trick instead.

   - By using get_random_u16() or get_random_u8() in cases where the
     return value is intended to indeed be a u16 or a u8, we waste fewer
     batched random bytes, and hence have higher throughput.

  This series was originally done by hand while I was on an airplane
  without Internet. Later, Kees and I worked on retroactively figuring
  out what could be done with Coccinelle and what had to be done
  manually, and then we split things up based on that.

  So while this touches a lot of files, the actual amount of code that's
  hand fiddled is comfortably small"

* tag 'random-6.1-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
  prandom: remove unused functions
  treewide: use get_random_bytes() when possible
  treewide: use get_random_u32() when possible
  treewide: use get_random_{u8,u16}() when possible, part 2
  treewide: use get_random_{u8,u16}() when possible, part 1
  treewide: use prandom_u32_max() when possible, part 2
  treewide: use prandom_u32_max() when possible, part 1
2022-10-16 15:27:07 -07:00
Jason A. Donenfeld
81895a65ec treewide: use prandom_u32_max() when possible, part 1
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() >> 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

-       RAND = get_random_u32();
        ... when != RAND
-       RAND %= (E);
+       RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p & (LITERAL))

// Add one to the literal.
@script:python add_one@
literal << literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
        print("Skipping 0x%x for cleanup elsewhere" % (value))
        cocci.include_match(False)
elif value & (value + 1) != 0:
        print("Skipping 0x%x because it's not a power of two minus one" % (value))
        cocci.include_match(False)
elif literal.startswith('0x'):
        coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
        coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p & (LITERAL))
+       prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

 {
-       T VAR;
-       VAR = (E);
-       return VAR;
+       return E;
 }

@drop_var@
type T;
identifier VAR;
@@

 {
-       T VAR;
        ... when != VAR
 }

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: KP Singh <kpsingh@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-10-11 17:42:55 -06:00
Zhihao Cheng
669d204469 ubi: fastmap: Add fastmap control support for 'UBI_IOCATT' ioctl
[1] suggests that fastmap is suitable for large flash devices. Module
parameter 'fm_autoconvert' is a coarse grained switch to enable all
ubi devices to generate fastmap, which may turn on fastmap even for
small flash devices.

This patch imports a new field 'disable_fm' in struct 'ubi_attach_req'
to support following situations by ioctl 'UBI_IOCATT'.
 [old functions]
 A. Disable 'fm_autoconvert': Disbable fastmap for all ubi devices
 B. Enable 'fm_autoconvert': Enable fastmap for all ubi devices
 [new function]
 C. Enable 'fm_autoconvert', set 'disable_fm' for given device: Don't
    create new fastmap and do full scan (existed fastmap will be
    destroyed) for the given ubi device.

A simple test case in [2].

[1] http://www.linux-mtd.infradead.org/doc/ubi.html#L_fastmap
[2] https://bugzilla.kernel.org/show_bug.cgi?id=216278

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-21 18:29:18 +02:00
Christophe JAILLET
e7f35da21f ubi: fastmap: Use the bitmap API to allocate bitmaps
Use bitmap_zalloc()/bitmap_free() instead of hand-writing them.

It is less verbose and it improves the semantic.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-21 11:32:58 +02:00
Jiang Jian
019ac05e4c mtd: ubi: drop unexpected word 'a' in comments
there is an unexpected word 'a' in the comments that need to be dropped

file - drivers/mtd/ubi/vmt.c
line - 626,779

* Returns zero if volume is all right and a a negative error code if not.

changed to:

* Returns zero if volume is all right and a negative error code if not.

Signed-off-by: Jiang Jian <jiangjian@cdjrlc.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-21 11:32:38 +02:00
Julia Lawall
e079be2c35 ubi: block: Fix typos in comments
Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-21 11:32:27 +02:00
Zhang Jiaming
b58b252800 ubi: fastmap: Fix typo in comments
There are a typo(dont't) in comments.
Fix it.

Signed-off-by: Zhang Jiaming <jiaming@nfschina.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-21 11:32:27 +02:00
Jilin Yuan
ec1f97f501 ubi: Fix repeated words in comments
Delete the redundant word 'a'.
Delete the redundant word 'the'.

Signed-off-by: Jilin Yuan <yuanjilin@cdjrlc.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-21 11:32:27 +02:00
Jason Wang
818f9e8353 ubi: ubi-media.h: Fix comment typo
The double `the' is duplicated in the comment, remove one.

Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-21 11:12:18 +02:00
Li zeming
6c97bb345f ubi: block: Remove in vain semicolon
Remove the repeated ';' from code, it is not
needed.

Signed-off-by: Li zeming <zeming@nfschina.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
[rw: Massaged commit message a bit]
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-21 11:11:10 +02:00
Christoph Hellwig
8b9ab62662 block: remove blk_cleanup_disk
blk_cleanup_disk is nothing but a trivial wrapper for put_disk now,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20220619060552.1850436-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-28 06:33:15 -06:00
Zhihao Cheng
8c03a1c21d ubi: ubi_create_volume: Fix use-after-free when volume creation failed
There is an use-after-free problem for 'eba_tbl' in ubi_create_volume()'s
error handling path:

  ubi_eba_replace_table(vol, eba_tbl)
    vol->eba_tbl = tbl
out_mapping:
  ubi_eba_destroy_table(eba_tbl)   // Free 'eba_tbl'
out_unlock:
  put_device(&vol->dev)
    vol_release
      kfree(tbl->entries)	  // UAF

Fix it by removing redundant 'eba_tbl' releasing.
Fetch a reproducer in [Link].

Fixes: 493cfaeaa0 ("mtd: utilize new cdev_device_add helper function")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215965
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-05-27 16:49:41 +02:00
Zhihao Cheng
14072ee33d ubi: fastmap: Check wl_pool for free peb before wear leveling
UBI fetches free peb from wl_pool during wear leveling, so UBI should
check wl_pool's empty status before wear leveling. Otherwise, UBI will
miss wear leveling chances when free pebs are run out.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-05-27 16:49:07 +02:00
Zhihao Cheng
d09e9a2bdd ubi: fastmap: Fix high cpu usage of ubi_bgt by making sure wl_pool not empty
There at least 6 PEBs reserved on UBI device:
1. EBA_RESERVED_PEBS[1]
2. WL_RESERVED_PEBS[1]
3. UBI_LAYOUT_VOLUME_EBS[2]
4. MIN_FASTMAP_RESERVED_PEBS[2]

When all ubi volumes take all their PEBs, there are 3 (EBA_RESERVED_PEBS +
WL_RESERVED_PEBS + MIN_FASTMAP_RESERVED_PEBS - MIN_FASTMAP_TAKEN_PEBS[1])
free PEBs. Since commit f9c34bb529 ("ubi: Fix producing anchor PEBs")
and commit 4b68bf9a69 ("ubi: Select fastmap anchor PEBs considering
wear level rules") applied, there is only 1 (3 - FASTMAP_ANCHOR_PEBS[1] -
FASTMAP_NEXT_ANCHOR_PEBS[1]) free PEB to fill pool and wl_pool, after
filling pool, wl_pool is always empty. So, UBI could be stuck in an
infinite loop:

	ubi_thread	   system_wq
wear_leveling_worker <--------------------------------------------------
  get_peb_for_wl							|
    // fm_wl_pool, used = size = 0					|
    schedule_work(&ubi->fm_work)					|
									|
		    update_fastmap_work_fn				|
		      ubi_update_fastmap				|
			ubi_refill_pools				|
			// ubi->free_count - ubi->beb_rsvd_pebs < 5	|
			// wl_pool is not filled with any PEBs		|
			schedule_erase(old_fm_anchor)			|
			ubi_ensure_anchor_pebs				|
			  __schedule_ubi_work(wear_leveling_worker)	|
									|
__erase_worker								|
  ensure_wear_leveling							|
    __schedule_ubi_work(wear_leveling_worker) --------------------------

, which cause high cpu usage of ubi_bgt:
top - 12:10:42 up 5 min,  2 users,  load average: 1.76, 0.68, 0.27
Tasks: 123 total,   3 running,  54 sleeping,   0 stopped,   0 zombie

  PID USER PR   NI VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND
 1589 root 20   0   0      0      0 R  45.0  0.0   0:38.86 ubi_bgt0d
  319 root 20   0   0      0      0 I  15.2  0.0   0:15.29 kworker/0:3-eve
  371 root 20   0   0      0      0 I  14.9  0.0   0:12.85 kworker/3:3-eve
   20 root 20   0   0      0      0 I  11.3  0.0   0:05.33 kworker/1:0-eve
  202 root 20   0   0      0      0 I  11.3  0.0   0:04.93 kworker/2:3-eve

In commit 4b68bf9a69 ("ubi: Select fastmap anchor PEBs considering
wear level rules"), there are three key changes:
  1) Choose the fastmap anchor when the most free PEBs are available.
  2) Enable anchor move within the anchor area again as it is useful
     for distributing wear.
  3) Import a candidate fm anchor and check this PEB's erase count during
     wear leveling. If the wear leveling limit is exceeded, use the used
     anchor area PEB with the lowest erase count to replace it.

The anchor candidate can be removed, we can check fm_anchor PEB's erase
count during wear leveling. Fix it by:
  1) Removing 'fm_next_anchor' and check 'fm_anchor' during wear leveling.
  2) Preferentially filling one free peb into fm_wl_pool in condition of
     ubi->free_count > ubi->beb_rsvd_pebs, then try to reserve enough
     free count for fastmap non anchor pebs after the above prerequisites
     are met.
Then, there are at least 1 PEB in pool and 1 PEB in wl_pool after calling
ubi_refill_pools() with all erase works done.

Fetch a reproducer in [Link].

Fixes: 4b68bf9a69 ("ubi: Select fastmap anchor PEBs ... rules")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215407
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-05-27 16:46:02 +02:00
Linus Torvalds
a87a08e3bf This pull request contains fixes for JFFS2, UBI and UBIFS
JFFS2:
         - Fixes for various memory issues
 
 UBI:
         - Fix for a race condition in cdev ioctl handler
 
 UBIFS:
 	- Fixes for O_TMPFILE and whiteout handling
 	- Fixes for various memory issues
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Merge tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs

Pull JFFS2, UBI and UBIFS updates from Richard Weinberger:
 "JFFS2:
   - Fixes for various memory issues

  UBI:
   - Fix for a race condition in cdev ioctl handler

  UBIFS:
   - Fixes for O_TMPFILE and whiteout handling

   - Fixes for various memory issues"

* tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubifs: rename_whiteout: correct old_dir size computing
  jffs2: fix memory leak in jffs2_scan_medium
  jffs2: fix memory leak in jffs2_do_mount_fs
  jffs2: fix use-after-free in jffs2_clear_xattr_subsystem
  fs/jffs2: fix comments mentioning i_mutex
  ubi: fastmap: Return error code if memory allocation fails in add_aeb()
  ubifs: Fix to add refcount once page is set private
  ubifs: Fix read out-of-bounds in ubifs_wbuf_write_nolock()
  ubifs: setflags: Make dirtied_ino_d 8 bytes aligned
  ubifs: Rectify space amount budget for mkdir/tmpfile operations
  ubifs: Fix 'ui->dirty' race between do_tmpfile() and writeback work
  ubifs: Rename whiteout atomically
  ubifs: Add missing iput if do_tmpfile() failed in rename whiteout
  ubifs: Fix wrong number of inodes locked by ui_mutex in ubifs_inode comment
  ubifs: Fix deadlock in concurrent rename whiteout and inode writeback
  ubifs: rename_whiteout: Fix double free for whiteout_ui->data
  ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
2022-03-31 16:09:41 -07:00
Linus Torvalds
d3c8108035 for-5.17/block-2022-01-11
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Merge tag 'for-5.17/block-2022-01-11' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - Unify where the struct request handling code is located in the blk-mq
   code (Christoph)

 - Header cleanups (Christoph)

 - Clean up the io_context handling code (Christoph, me)

 - Get rid of ->rq_disk in struct request (Christoph)

 - Error handling fix for add_disk() (Christoph)

 - request allocation cleanusp (Christoph)

 - Documentation updates (Eric, Matthew)

 - Remove trivial crypto unregister helper (Eric)

 - Reduce shared tag overhead (John)

 - Reduce poll_stats memory overhead (me)

 - Known indirect function call for dio (me)

 - Use atomic references for struct request (me)

 - Support request list issue for block and NVMe (me)

 - Improve queue dispatch pinning (Ming)

 - Improve the direct list issue code (Keith)

 - BFQ improvements (Jan)

 - Direct completion helper and use it in mmc block (Sebastian)

 - Use raw spinlock for the blktrace code (Wander)

 - fsync error handling fix (Ye)

 - Various fixes and cleanups (Lukas, Randy, Yang, Tetsuo, Ming, me)

* tag 'for-5.17/block-2022-01-11' of git://git.kernel.dk/linux-block: (132 commits)
  MAINTAINERS: add entries for block layer documentation
  docs: block: remove queue-sysfs.rst
  docs: sysfs-block: document virt_boundary_mask
  docs: sysfs-block: document stable_writes
  docs: sysfs-block: fill in missing documentation from queue-sysfs.rst
  docs: sysfs-block: add contact for nomerges
  docs: sysfs-block: sort alphabetically
  docs: sysfs-block: move to stable directory
  block: don't protect submit_bio_checks by q_usage_counter
  block: fix old-style declaration
  nvme-pci: fix queue_rqs list splitting
  block: introduce rq_list_move
  block: introduce rq_list_for_each_safe macro
  block: move rq_list macros to blk-mq.h
  block: drop needless assignment in set_task_ioprio()
  block: remove unnecessary trailing '\'
  bio.h: fix kernel-doc warnings
  block: check minor range in device_add_disk()
  block: use "unsigned long" for blk_validate_block_size().
  block: fix error unwinding in device_add_disk
  ...
2022-01-12 10:26:52 -08:00
Zhihao Cheng
c3c07fc25f ubi: fastmap: Return error code if memory allocation fails in add_aeb()
Abort fastmap scanning and return error code if memory allocation fails
in add_aeb(). Otherwise ubi will get wrong peb statistics information
after scanning.

Fixes: dbb7d2a88d ("UBI: Add fastmap core")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-01-10 23:09:08 +01:00
Baokun Li
3cbf0e392f ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
Hulk Robot reported a KASAN report about use-after-free:
 ==================================================================
 BUG: KASAN: use-after-free in __list_del_entry_valid+0x13d/0x160
 Read of size 8 at addr ffff888035e37d98 by task ubiattach/1385
 [...]
 Call Trace:
  klist_dec_and_del+0xa7/0x4a0
  klist_put+0xc7/0x1a0
  device_del+0x4d4/0xed0
  cdev_device_del+0x1a/0x80
  ubi_attach_mtd_dev+0x2951/0x34b0 [ubi]
  ctrl_cdev_ioctl+0x286/0x2f0 [ubi]

 Allocated by task 1414:
  device_add+0x60a/0x18b0
  cdev_device_add+0x103/0x170
  ubi_create_volume+0x1118/0x1a10 [ubi]
  ubi_cdev_ioctl+0xb7f/0x1ba0 [ubi]

 Freed by task 1385:
  cdev_device_del+0x1a/0x80
  ubi_remove_volume+0x438/0x6c0 [ubi]
  ubi_cdev_ioctl+0xbf4/0x1ba0 [ubi]
 [...]
 ==================================================================

The lock held by ctrl_cdev_ioctl is ubi_devices_mutex, but the lock held
by ubi_cdev_ioctl is ubi->device_mutex. Therefore, the two locks can be
concurrent.

ctrl_cdev_ioctl contains two operations: ubi_attach and ubi_detach.
ubi_detach is bug-free because it uses reference counting to prevent
concurrency. However, uif_init and uif_close in ubi_attach may race with
ubi_cdev_ioctl.

uif_init will race with ubi_cdev_ioctl as in the following stack.
           cpu1                   cpu2                  cpu3
_______________________|________________________|______________________
ctrl_cdev_ioctl
 ubi_attach_mtd_dev
  uif_init
                           ubi_cdev_ioctl
                            ubi_create_volume
                             cdev_device_add
   ubi_add_volume
   // sysfs exist
   kill_volumes
                                                    ubi_cdev_ioctl
                                                     ubi_remove_volume
                                                      cdev_device_del
                                                       // first free
    ubi_free_volume
     cdev_del
     // double free
   cdev_device_del

And uif_close will race with ubi_cdev_ioctl as in the following stack.
           cpu1                   cpu2                  cpu3
_______________________|________________________|______________________
ctrl_cdev_ioctl
 ubi_attach_mtd_dev
  uif_init
                           ubi_cdev_ioctl
                            ubi_create_volume
                             cdev_device_add
  ubi_debugfs_init_dev
  //error goto out_uif;
  uif_close
   kill_volumes
                                                    ubi_cdev_ioctl
                                                     ubi_remove_volume
                                                      cdev_device_del
                                                       // first free
    ubi_free_volume
    // double free

The cause of this problem is that commit 714fb87e8b make device
"available" before it becomes accessible via sysfs. Therefore, we
roll back the modification. We will fix the race condition between
ubi device creation and udev by removing ubi_get_device in
vol_attribute_show and dev_attribute_show.This avoids accessing
uninitialized ubi_devices[ubi_num].

ubi_get_device is used to prevent devices from being deleted during
sysfs execution. However, now kernfs ensures that devices will not
be deleted before all reference counting are released.
The key process is shown in the following stack.

device_del
  device_remove_attrs
    device_remove_groups
      sysfs_remove_groups
        sysfs_remove_group
          remove_files
            kernfs_remove_by_name
              kernfs_remove_by_name_ns
                __kernfs_remove
                  kernfs_drain

Fixes: 714fb87e8b ("ubi: Fix race condition between ubi device creation and udev")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2022-01-09 21:13:28 +01:00
Kai Song
bc7849e280 ubi: Fix a mistake in comment
Fixes: 2a734bb8d5 ("UBI: use debugfs for the extra checks knobs")
There is a mistake in docstrings, it should be ubi_debugfs_exit_dev
instead of dbg_debug_exit_dev.

Signed-off-by: Kai Song <songkai01@inspur.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-23 20:23:40 +01:00