linux-toradex.git/drivers/md, branch v3.18.21

md/bitmap: return an error when bitmap superblock is corrupt.

2015-08-27T17:25:54+00:00

[ Upstream commit HEAD ]

commit b97e92574c0bf335db1cd2ec491d8ff5cd5d0b49 upstream
    Use separate bitmaps for each nodes in the cluster

bitmap_read_sb() validates the bitmap superblock that it reads in.
If it finds an inconsistency like a bad magic number or out-of-range
version number, it prints an error and returns, but it incorrectly
returns zero, so the array is still assembled with the (invalid) bitmap.

This means it could try to use a bitmap with a new version number which
it therefore does not understand.

This bug was introduced in 3.5 and fix as part of a larger patch in 4.1.
So the patch is suitable for any -stable kernel in that range.

Fixes: 27581e5ae01f ("md/bitmap: centralise allocation of bitmap file pages.")
Signed-off-by: NeilBrown 
Reported-by: GuoQing Jiang 

(cherry picked from commit ed9691677d6dda3fff331673f44d18e85938bd76)
Signed-off-by: Sasha Levin

md/raid1: fix test for 'was read error from last working device'.

2015-08-27T17:25:44+00:00

[ Upstream commit 34cab6f42003cb06f48f86a86652984dec338ae9 ]

When we get a read error from the last working device, we don't
try to repair it, and don't fail the device.  We simple report a
read error to the caller.

However the current test for 'is this the last working device' is
wrong.
When there is only one fully working device, it assumes that a
non-faulty device is that device.  However a spare which is rebuilding
would be non-faulty but so not the only working device.

So change the test from "!Faulty" to "In_sync".  If ->degraded says
there is only one fully working device and this device is in_sync,
this must be the one.

This bug has existed since we allowed read_balance to read from
a recovering spare in v3.0

Reported-and-tested-by: Alexander Lyakas 
Fixes: 76073054c95b ("md/raid1: clean up read_balance.")
Cc: stable@vger.kernel.org (v3.0+)
Signed-off-by: NeilBrown 
Signed-off-by: Sasha Levin

md/raid1: extend spinlock to protect raid1_end_read_request against inconsistencies

2015-08-27T17:25:33+00:00

[ Upstream commit 423f04d63cf421ea436bcc5be02543d549ce4b28 ]

raid1_end_read_request() assumes that the In_sync bits are consistent
with the ->degaded count.
raid1_spare_active updates the In_sync bit before the ->degraded count
and so exposes an inconsistency, as does error()
So extend the spinlock in raid1_spare_active() and error() to hide those
inconsistencies.

This should probably be part of
  Commit: 34cab6f42003 ("md/raid1: fix test for 'was read error from
  last working device'.")
as it addresses the same issue.  It fixes the same bug and should go
to -stable for same reasons.

Fixes: 76073054c95b ("md/raid1: clean up read_balance.")
Cc: stable@vger.kernel.org (v3.0+)
Signed-off-by: NeilBrown 
Signed-off-by: Sasha Levin

md: use kzalloc() when bitmap is disabled

2015-08-20T21:33:11+00:00

[ Upstream commit 33afeac21b9cb79ad8fc5caf239af89c79e25e1e ]

commit b6878d9e03043695dbf3fa1caa6dfc09db225b16 upstream.

In drivers/md/md.c get_bitmap_file() uses kmalloc() for creating a
mdu_bitmap_file_t called "file".

5769         file = kmalloc(sizeof(*file), GFP_NOIO);
5770         if (!file)
5771                 return -ENOMEM;

This structure is copied to user space at the end of the function.

5786         if (err == 0 &&
5787             copy_to_user(arg, file, sizeof(*file)))
5788                 err = -EFAULT

But if bitmap is disabled only the first byte of "file" is initialized
with zero, so it's possible to read some bytes (up to 4095) of kernel
space memory from user space. This is an information leak.

5775         /* bitmap disabled, zero the first byte and copy out */
5776         if (!mddev->bitmap_info.file)
5777                 file->pathname[0] = '\0';

Signed-off-by: Benjamin Randazzo 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

md: fix a build warning

2015-08-04T18:31:58+00:00

[ Upstream commit 4e023612325a9034a542bfab79f78b1fe5ebb841 ]

Warning like this:

drivers/md/md.c: In function "update_array_info":
drivers/md/md.c:6394:26: warning: logical not is only applied
to the left hand side of comparison [-Wlogical-not-parentheses]
      !mddev->persistent  != info->not_persistent||

Fix it as Neil Brown said:
mddev->persistent != !info->not_persistent ||

Signed-off-by: Firo Yang 
Signed-off-by: NeilBrown 
Signed-off-by: Sasha Levin

dm btree: silence lockdep lock inversion in dm_btree_del()

2015-08-04T18:24:53+00:00

[ Upstream commit 1c7518794a3647eb345d59ee52844e8a40405198 ]

Allocate memory using GFP_NOIO when deleting a btree.  dm_btree_del()
can be called via an ioctl and we don't want to recurse into the FS or
block layer.

Signed-off-by: Joe Thornber 
Signed-off-by: Mike Snitzer 
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin

dm btree remove: fix bug in redistribute3

2015-08-04T18:24:35+00:00

[ Upstream commit 4c7e309340ff85072e96f529582d159002c36734 ]

redistribute3() shares entries out across 3 nodes.  Some entries were
being moved the wrong way, breaking the ordering.  This manifested as a
BUG() in dm-btree-remove.c:shift() when entries were removed from the
btree.

For additional context see:
https://www.redhat.com/archives/dm-devel/2015-May/msg00113.html

Signed-off-by: Dennis Yang 
Signed-off-by: Joe Thornber 
Signed-off-by: Mike Snitzer 
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin

dm stats: fix divide by zero if 'number_of_areas' arg is zero

2015-07-04T03:02:33+00:00

[ Upstream commit dd4c1b7d0c95be1c9245118a3accc41a16f1db67 ]

If the number_of_areas argument was zero the kernel would crash on
div-by-zero.  Add better input validation.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer 
Cc: stable@vger.kernel.org # v3.12+
Signed-off-by: Sasha Levin

dm space map metadata: fix occasional leak of a metadata block on resize

2015-07-04T03:02:32+00:00

[ Upstream commit 6096d91af0b65a3967139b32d5adbb3647858a26 ]

The metadata space map has a simplified 'bootstrap' mode that is
operational when extending the space maps.  Whilst in this mode it's
possible for some refcount decrement operations to become queued (eg, as
a result of shadowing one of the bitmap indexes).  These decrements were
not being applied when switching out of bootstrap mode.

The effect of this bug was the leaking of a 4k metadata block.  This is
detected by the latest version of thin_check as a non fatal error.

Signed-off-by: Joe Thornber 
Signed-off-by: Mike Snitzer 
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin

md/raid0: fix restore to sector variable in raid0_make_request

2015-06-14T16:14:45+00:00

[ Upstream commit a81157768a00e8cf8a7b43b5ea5cac931262374f ]

The variable "sector" in "raid0_make_request()" was improperly updated
by a call to "sector_div()" which modifies its first argument in place.
Commit 47d68979cc968535cb87f3e5f2e6a3533ea48fbd restored this variable
after the call for later re-use.  Unfortunetly the restore was done after
the referenced variable "bio" was advanced.  This lead to the original
value and the restored value being different.  Here we move this line to
the proper place.

One observed side effect of this bug was discarding a file though
unlinking would cause an unrelated file's contents to be discarded.

Signed-off-by: NeilBrown 
Fixes: 47d68979cc96 ("md/raid0: fix bug with chunksize not a power of 2.")
Cc: stable@vger.kernel.org (any that received above backport)
URL: https://bugzilla.kernel.org/show_bug.cgi?id=98501
Signed-off-by: Sasha Levin