linux-stable.git/drivers/mtd, branch v4.1.35

ubi: Make volume resize power cut aware

2016-08-20T03:07:58+00:00

[ Upstream commit 4946784bd3924b1374f05eebff2fd68660bae866 ]

When the volume resize operation shrinks a volume,
LEBs will be unmapped. Since unmapping will not erase these
LEBs immediately we have to wait for that operation to finish.
Otherwise in case of a power cut right after writing the new
volume table the UBI attach process can find more LEBs than the
volume table knows. This will render the UBI image unattachable.

Fix this issue by waiting for erase to complete and write the new
volume table afterward.

Cc: 
Reported-by: Boris Brezillon 
Reviewed-by: Boris Brezillon 
Signed-off-by: Richard Weinberger 
Signed-off-by: Sasha Levin

ubi: Fix early logging

2016-08-20T03:07:58+00:00

[ Upstream commit bc743f34dfa011e62edd0ea4ae8455be06c083b5 ]

We cannot use ubi_* logging functions before the UBI
object is initialized.

Cc: 
Fixes: 3260870331 ("UBI: Extend UBI layer debug/messaging capabilities")
Signed-off-by: Richard Weinberger 
Signed-off-by: Sasha Levin

ubi: Fix race condition between ubi device creation and udev

2016-08-20T03:07:58+00:00

[ Upstream commit 714fb87e8bc05ff78255afc0dca981e8c5242785 ]

Install the UBI device object before we arm sysfs.
Otherwise udev tries to read sysfs attributes before UBI is ready and
udev rules will not match.

Cc: 
Signed-off-by: Iosif Harutyunov 
[rw: massaged commit message]
Signed-off-by: Richard Weinberger 

Signed-off-by: Sasha Levin

mtd: nand: fix bug writing 1 byte less than page size

2016-08-20T03:07:58+00:00

[ Upstream commit 144f4c98399e2c0ca60eb414c15a2c68125c18b8 ]

nand_do_write_ops() determines if it is writing a partial page with the
formula:
	part_pagewr = (column || writelen < (mtd->writesize - 1))

When 'writelen' is exactly 1 byte less than the NAND page size the formula
equates to zero, so the code doesn't process it as a partial write,
although it should.
As a consequence the function remains in the while(1) loop with 'writelen'
becoming 0xffffffff and iterating endlessly.

The bug may not be easy to reproduce in Linux since user space tools
usually force the padding or round-up the write size to a page-size
multiple.
This was discovered in U-Boot where the issue can be reproduced by
writing any size that is 1 byte less than a page-size multiple.
For example, on a NAND with 2K page (0x800):
	=> nand erase.part 
	=> nand write $loadaddr  7ff

[Editor's note: the bug was added in commit 29072b96078f, but moved
around in commit 66507c7bc8895 ("mtd: nand: Add support to use nand_base
poi databuf as bounce buffer")]

Fixes: 29072b96078f ("[MTD] NAND: add subpage write support")
Signed-off-by: Hector Palacios 
Acked-by: Boris Brezillon 
Cc: 
Signed-off-by: Brian Norris 
Signed-off-by: Sasha Levin

ubi: Make recover_peb power cut aware

2016-07-11T00:20:01+00:00

[ Upstream commit 972228d87445dc46c0a01f5f3de673ac017626f7 ]

recover_peb() was never power cut aware,
if a power cut happened right after writing the VID header
upon next attach UBI would blindly use the new partial written
PEB and all data from the old PEB is lost.

In order to make recover_peb() power cut aware, write the new
VID with a proper crc and copy_flag set such that the UBI attach
process will detect whether the new PEB is completely written
or not.
We cannot directly use ubi_eba_atomic_leb_change() since we'd
have to unlock the LEB which is facing a write error.

Cc: stable@vger.kernel.org
Reported-by: Jörg Pfähler 
Reviewed-by: Jörg Pfähler 
Signed-off-by: Richard Weinberger 
Signed-off-by: Sasha Levin

UBI: Fix static volume checks when Fastmap is used

2016-06-06T23:12:34+00:00

[ Upstream commit 1900149c835ab5b48bea31a823ea5e5a401fb560 ]

Ezequiel reported that he's facing UBI going into read-only
mode after power cut. It turned out that this behavior happens
only when updating a static volume is interrupted and Fastmap is
used.

A possible trace can look like:
ubi0 warning: ubi_io_read_vid_hdr [ubi]: no VID header found at PEB 2323, only 0xFF bytes
ubi0 warning: ubi_eba_read_leb [ubi]: switch to read-only mode
CPU: 0 PID: 833 Comm: ubiupdatevol Not tainted 4.6.0-rc2-ARCH #4
Hardware name: SAMSUNG ELECTRONICS CO., LTD. 300E4C/300E5C/300E7C/NP300E5C-AD8AR, BIOS P04RAP 10/15/2012
0000000000000286 00000000eba949bd ffff8800c45a7b38 ffffffff8140d841
ffff8801964be000 ffff88018eaa4800 ffff8800c45a7bb8 ffffffffa003abf6
ffffffff850e2ac0 8000000000000163 ffff8801850e2ac0 ffff8801850e2ac0
Call Trace:
[] dump_stack+0x63/0x82
[] ubi_eba_read_leb+0x486/0x4a0 [ubi]
[] ubi_check_volume+0x83/0xf0 [ubi]
[] ubi_open_volume+0x177/0x350 [ubi]
[] vol_cdev_open+0x58/0xb0 [ubi]
[] chrdev_open+0xae/0x1d0
[] do_dentry_open+0x1ff/0x300
[] ? cdev_put+0x30/0x30
[] vfs_open+0x56/0x60
[] path_openat+0x4f4/0x1190
[] do_filp_open+0x91/0x100
[] ? __alloc_fd+0xc7/0x190
[] do_sys_open+0x13f/0x210
[] SyS_open+0x1e/0x20
[] entry_SYSCALL_64_fastpath+0x1a/0xa4

UBI checks static volumes for data consistency and reads the
whole volume upon first open. If the volume is found erroneous
users of UBI cannot read from it, but another volume update is
possible to fix it. The check is performed by running
ubi_eba_read_leb() on every allocated LEB of the volume.
For static volumes ubi_eba_read_leb() computes the checksum of all
data stored in a LEB. To verify the computed checksum it has to read
the LEB's volume header which stores the original checksum.
If the volume header is not found UBI treats this as fatal internal
error and switches to RO mode. If the UBI device was attached via a
full scan the assumption is correct, the volume header has to be
present as it had to be there while scanning to get known as mapped.
If the attach operation happened via Fastmap the assumption is no
longer correct. When attaching via Fastmap UBI learns the mapping
table from Fastmap's snapshot of the system state and not via a full
scan. It can happen that a LEB got unmapped after a Fastmap was
written to the flash. Then UBI can learn the LEB still as mapped and
accessing it returns only 0xFF bytes. As UBI is not a FTL it is
allowed to have mappings to empty PEBs, it assumes that the layer
above takes care of LEB accounting and referencing.
UBIFS does so using the LEB property tree (LPT).
For static volumes UBI blindly assumes that all LEBs are present and
therefore special actions have to be taken.

The described situation can happen when updating a static volume is
interrupted, either by a user or a power cut.
The volume update code first unmaps all LEBs of a volume and then
writes LEB by LEB. If the sequence of operations is interrupted UBI
detects this either by the absence of LEBs, no volume header present
at scan time, or corrupted payload, detected via checksum.
In the Fastmap case the former method won't trigger as no scan
happened and UBI automatically thinks all LEBs are present.
Only by reading data from a LEB it detects that the volume header is
missing and incorrectly treats this as fatal error.
To deal with the situation ubi_eba_read_leb() from now on checks
whether we attached via Fastmap and handles the absence of a
volume header like a data corruption error.
This way interrupted static volume updates will correctly get detected
also when Fastmap is used.

Cc: 
Reported-by: Ezequiel Garcia 
Tested-by: Ezequiel Garcia 
Signed-off-by: Richard Weinberger 
Signed-off-by: Sasha Levin

mtd: onenand: fix deadlock in onenand_block_markbad

2016-04-18T12:50:40+00:00

[ Upstream commit 5e64c29e98bfbba1b527b0a164f9493f3db9e8cb ]

Commit 5942ddbc500d ("mtd: introduce mtd_block_markbad interface")
incorrectly changed onenand_block_markbad() to call mtd_block_markbad
instead of onenand_chip's block_markbad function. As a result the function
will now recurse and deadlock. Fix by reverting the change.

Fixes: 5942ddbc500d ("mtd: introduce mtd_block_markbad interface")
Signed-off-by: Aaro Koskinen 
Acked-by: Artem Bityutskiy 
Cc: 
Signed-off-by: Brian Norris 
Signed-off-by: Sasha Levin

ubi: Fix out of bounds write in volume update code

2016-03-14T16:42:31+00:00

[ Upstream commit e4f6daac20332448529b11f09388f1d55ef2084c ]

ubi_start_leb_change() allocates too few bytes.
ubi_more_leb_change_data() will write up to req->upd_bytes +
ubi->min_io_size bytes.

Cc: stable@vger.kernel.org
Signed-off-by: Richard Weinberger 
Reviewed-by: Boris Brezillon 
Signed-off-by: Sasha Levin

UBI: return ENOSPC if no enough space available

2015-10-22T21:43:24+00:00

commit 7c7feb2ebfc9c0552c51f0c050db1d1a004faac5 upstream.

UBI: attaching mtd1 to ubi0
UBI: scanning is finished
UBI error: init_volumes: not enough PEBs, required 706, available 686
UBI error: ubi_wl_init: no enough physical eraseblocks (-20, need 1)
UBI error: ubi_attach_mtd_dev: failed to attach mtd1, error -12 <= NOT ENOMEM
UBI error: ubi_init: cannot attach mtd1

If available PEBs are not enough when initializing volumes, return -ENOSPC
directly. If available PEBs are not enough when initializing WL, return
-ENOSPC instead of -ENOMEM.

Signed-off-by: Sheng Yong 
Signed-off-by: Richard Weinberger 
Reviewed-by: David Gstir 
Signed-off-by: Greg Kroah-Hartman

UBI: Validate data_size

2015-10-22T21:43:24+00:00

commit 281fda27673f833a01d516658a64d22a32c8e072 upstream.

Make sure that data_size is less than LEB size.
Otherwise a handcrafted UBI image is able to trigger
an out of bounds memory access in ubi_compare_lebs().

Signed-off-by: Richard Weinberger 
Reviewed-by: David Gstir 
Signed-off-by: Greg Kroah-Hartman