linux-stable.git/drivers/md, branch v3.5.7

dm verity: fix overflow check

2012-10-07T15:35:50+00:00

commit 1d55f6bcc0331d744cd5b56c4ee79e3809438161 upstream.

This patch fixes sector_t overflow checking in dm-verity.

Without this patch, the code checks for overflow only if sector_t is
smaller than long long, not if sector_t and long long have the same size.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

dm table: clear add_random unless all devices have it set

2012-10-07T15:35:50+00:00

commit c3c4555edd10dbc0b388a0125b9c50de5e79af05 upstream.

Always clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not
have it set. Otherwise devices with predictable characteristics may
contribute entropy.

QUEUE_FLAG_ADD_RANDOM specifies whether or not queue IO timings
contribute to the random pool.

For bio-based targets this flag is always 0 because such devices have no
real queue.

For request-based devices this flag was always set to 1 by default.

Now set it according to the flags on underlying devices. If there is at
least one device which should not contribute, set the flag to zero: If a
device, such as fast SSD storage, is not suitable for supplying entropy,
a request-based queue stacked over it will not be either.

Because the checking logic is exactly same as for the rotational flag,
share the iteration function with device_is_nonrot().

Signed-off-by: Milan Broz 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

dm: handle requests beyond end of device instead of using BUG_ON

2012-10-07T15:35:50+00:00

commit ba1cbad93dd47223b1f3b8edd50dd9ef2abcb2ed upstream.

The access beyond the end of device BUG_ON that was introduced to
dm_request_fn via commit 29e4013de7ad950280e4b2208 ("dm: implement
REQ_FLUSH/FUA support for request-based dm") was an overly
drastic (but simple) response to this situation.

I have received a report that this BUG_ON was hit and now think
it would be better to use dm_kill_unmapped_request() to fail the clone
and original request with -EIO.

map_request() will assign the valid target returned by
dm_table_find_target to tio->ti.  But when the target
isn't valid tio->ti is never assigned (because map_request isn't
called); so add a check for tio->ti != NULL to dm_done().

Reported-by: Mike Christie 
Signed-off-by: Mike Snitzer 
Signed-off-by: Jun'ichi Nomura 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

dm mpath: only retry ioctl when no paths if queue_if_no_path set

2012-10-07T15:35:50+00:00

commit 7ba10aa6fbac7158a50bec142132b04bc480bb29 upstream.

When there are no paths and multipath receives an ioctl, it waits until
a path becomes available.  This behaviour is incorrect if the
"queue_if_no_path" setting was not specified, as then the ioctl should
be rejected immediately, which this patch now does.

commit 35991652b ("dm mpath: allow ioctls to trigger pg init") should
have checked if queue_if_no_path was configured before queueing IO.

Checking for the queue_if_no_path feature, like is done in map_io(),
allows the following table load to work without blocking in the
multipath_ioctl retry loop:

  echo "0 1024 multipath 0 0 0 0" | dmsetup create mpath_nodevs

Without this fix the multipath_ioctl will block with the following stack
trace:

  blkid           D 0000000000000002     0 23936      1 0x00000000
   ffff8802b89e5cd8 0000000000000082 ffff8802b89e5fd8 0000000000012440
   ffff8802b89e4010 0000000000012440 0000000000012440 0000000000012440
   ffff8802b89e5fd8 0000000000012440 ffff88030c2aab30 ffff880325794040
  Call Trace:
   [] schedule+0x29/0x70
   [] schedule_timeout+0x182/0x2e0
   [] ? lock_timer_base+0x70/0x70
   [] schedule_timeout_uninterruptible+0x1e/0x20
   [] msleep+0x20/0x30
   [] multipath_ioctl+0x109/0x170 [dm_multipath]
   [] dm_blk_ioctl+0xbc/0xd0 [dm_mod]
   [] __blkdev_driver_ioctl+0x28/0x30
   [] blkdev_ioctl+0xce/0x730
   [] block_ioctl+0x3c/0x40
   [] do_vfs_ioctl+0x8c/0x340
   [] ? sys_newfstat+0x33/0x40
   [] sys_ioctl+0xa1/0xb0
   [] system_call_fastpath+0x16/0x1b

Signed-off-by: Mike Snitzer 
Acked-by: Mikulas Patocka 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

md/raid10: fix "enough" function for detecting if array is failed.

2012-10-02T17:40:03+00:00

commit 80b4812407c6b1f66a4f2430e69747a13f010839 upstream.

The 'enough' function is written to work with 'near' arrays only
in that is implicitly assumes that the offset from one 'group' of
devices to the next is the same as the number of copies.
In reality it is the number of 'near' copies.

So change it to make this number explicit.

This bug makes it possible to run arrays without enough drives
present, which is dangerous.
It is appropriate for an -stable kernel, but will almost certainly
need to be modified for some of them.

Reported-by: Jakub Husák 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md/raid5: fix calculate of 'degraded' when a replacement becomes active.

2012-10-02T17:39:10+00:00

commit e5c86471f933608db5d43679f84cb4346c32033e upstream.

When a replacement device becomes active, we mark the device that it
replaces as 'faulty' so that it can subsequently get removed.
However 'calc_degraded' only pays attention to the primary device, not
the replacement, so the array appears to become degraded, which is
wrong.

So teach 'calc_degraded' to consider any replacement if a primary
device is faulty.

This is suitable for -stable as an incorrect 'degraded' value can
confuse md and could lead to data corruption.
This is only relevant for 3.3 and later.

Reported-by: Robin Hill 
Reported-by: John Drescher 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md: make sure metadata is updated when spares are activated or removed.

2012-10-02T17:39:10+00:00

commit 6dafab6b1383e912cd252fa809570b484eb6e0dc upstream.

It isn't always necessary to update the metadata when spares are
removed as the presence-or-not of a spare isn't really important to
the integrity of an array.
Also activating a spare doesn't always require updating the metadata
as the update on 'recovery-completed' is usually sufficient.

However the introduction of 'replacement' devices have made these
transitions sometimes more important.  For example the 'Replacement'
flag isn't cleared until the original device is removed, so we need
to ensure a metadata update after that 'spare' is removed.

So set MD_CHANGE_DEVS whenever a spare is activated or removed, to
complement the current situation where it is set when a spare is added
or a device is failed (or a number of other less common situations).

This is suitable for -stable as out-of-data metadata could lead
to data corruption.
This is only relevant for 3.3 and later 9when 'replacement' as
introduced.

Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md/raid10: fix problem with on-stack allocation of r10bio structure.

2012-10-02T17:39:10+00:00

commit e0ee778528bbaad28a5c69d2e219269a3a096607 upstream.

A 'struct r10bio' has an array of per-copy information at the end.
This array is declared with size [0] and r10bio_pool_alloc allocates
enough extra space to store the per-copy information depending on the
number of copies needed.

So declaring a 'struct r10bio on the stack isn't going to work.  It
won't allocate enough space, and memory corruption will ensue.

So in the two places where this is done, declare a sufficiently large
structure and use that instead.

The two call-sites of this bug were introduced in 3.4 and 3.5
so this is suitable for both those kernels.  The patch will have to
be modified for 3.4 as it only has one bug.

Reported-by: Ivan Vasilyev 
Tested-by: Ivan Vasilyev 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md: Don't truncate size at 4TB for RAID0 and Linear

2012-10-02T17:39:10+00:00

commit 667a5313ecd7308d79629c0738b0db588b0b0a4e upstream.

commit 27a7b260f71439c40546b43588448faac01adb93
   md: Fix handling for devices from 2TB to 4TB in 0.90 metadata.

changed 0.90 metadata handling to truncated size to 4TB as that is
all that 0.90 can record.
However for RAID0 and Linear, 0.90 doesn't need to record the size, so
this truncation is not needed and causes working arrays to become too small.

So avoid the truncation for RAID0 and Linear

This bug was introduced in 3.1 and is suitable for any stable kernels
from then onwards.
As the offending commit was tagged for 'stable', any stable kernel
that it was applied to should also get this patch.  That includes
at least 2.6.32, 2.6.33 and 3.0. (Thanks to Ben Hutchings for
providing that list).

Signed-off-by: Neil Brown 
Signed-off-by: Greg Kroah-Hartman

md/raid1: don't abort a resync on the first badblock.

2012-08-15T14:52:46+00:00

commit b7219ccb33aa0df9949a60c68b5e9f712615e56f upstream.

If a resync of a RAID1 array with 2 devices finds a known bad block
one device it will neither read from, or write to, that device for
this block offset.
So there will be one read_target (The other device) and zero write
targets.
This condition causes md/raid1 to abort the resync assuming that it
has finished - without known bad blocks this would be true.

When there are no write targets because of the presence of bad blocks
we should only skip over the area covered by the bad block.
RAID10 already gets this right, raid1 doesn't.  Or didn't.

As this can cause a 'sync' to abort early and appear to have succeeded
it could lead to some data corruption, so it suitable for -stable.

Reported-by: Alexander Lyakas 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman