linux-stable.git/drivers/s390, branch v3.10.78

crypto: prefix module autoloading with "crypto-"

2015-01-30T01:40:57+00:00

commit 5d26a105b5a73e5635eae0629b42fa0a90e07b7b upstream.

This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:

https://lkml.org/lkml/2013/3/4/70

Signed-off-by: Kees Cook 
Signed-off-by: Herbert Xu 
Signed-off-by: Greg Kroah-Hartman

s390/3215: fix tty output containing tabs

2015-01-27T15:52:33+00:00

commit e512d56c799517f33b301d81e9a5e0ebf30c2d1e upstream.

git commit 37f81fa1f63ad38e16125526bb2769ae0ea8d332
"n_tty: do O_ONLCR translation as a single write"
surfaced a bug in the 3215 device driver. In combination this
broke tab expansion for tty ouput.

The cause is an asymmetry in the behaviour of tty3215_ops->write
vs tty3215_ops->put_char. The put_char function scans for '\t'
but the write function does not.

As the driver has logic for the '\t' expansion remove XTABS
from c_oflag of the initial termios as well.

Reported-by: Stephen Powell 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/3215: fix hanging console issue

2015-01-27T15:52:33+00:00

commit 26d766c60f4ea08cd14f0f3435a6db3d6cc2ae96 upstream.

The ccw_device_start in raw3215_start_io can fail. raw3215_try_io
does not check if the request could be started and removes any
pending timer. This can leave the system in a hanging state.
Check for pending request after raw3215_start_io and start a
timer if necessary.

Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/chsc: fix SEI usage on old FW levels

2014-05-13T11:59:42+00:00

commit 06cd7a874ec6e09d151aeb1fa8600e14f1ff89f6 upstream.

Using a notification type mask for the store event information chsc
is unsupported on some firmware levels. Retry SEI with that mask set
to zero (which is the old way of requesting only channel subsystem
related events).

Reported-and-tested-by: Stefan Haberland 
Reviewed-by: Peter Oberparleiter 
Signed-off-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/cio: fix driver callback initialization for ccw consoles

2014-05-06T14:55:27+00:00

commit 2253e8d79237c69086ded391e6767afe16972527 upstream.

ccw consoles are in use before they can be properly registered with
the driver core. For devices which are in use by a device driver we
rely on the ccw_device's pointer to the driver callbacks to be valid.
For ccw consoles this pointer is NULL until they are registered later
during boot and we dereferenced this pointer. This worked by
chance on 64 bit builds (cdev->drv was NULL but the optional callback
cdev->drv->path_event was also NULL by coincidence) and was unnoticed
until we received reports about boot failures on 31 bit systems.
Fix it by initializing the driver pointer for ccw consoles.

Reported-by: Mike Frysinger 
Reported-by: Heiko Carstens 
Reviewed-by: Peter Oberparleiter 
Signed-off-by: Sebastian Ott 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/dasd: hold request queue sysfs lock when calling elevator_init()

2014-03-24T04:38:20+00:00

commit ef0899410ff630b2e75306da49996dbbfa318165 upstream.

"elevator: Fix a race in elevator switching and md device initialization"
changed the semantics of elevator_init() in a way that now enforces to hold
the corresponding request queue's sysfs_lock when calling elevator_init()
to fix a race.
The patch did not convert the s390 dasd device driver which is the only
device driver which also calls elevator_init(). So add the missing locking.

Cc: Tomoki Sekiyama 
Cc: Jens Axboe 
Signed-off-by: Heiko Carstens 
Signed-off-by: Jens Axboe 
Cc: Christian Borntraeger 
Signed-off-by: Greg Kroah-Hartman

s390/3270: fix allocation of tty3270_screen structure

2014-01-09T20:24:24+00:00

commit 36d9f4d3b68c7035ead3850dc85f310a579ed0eb upstream.

The tty3270_alloc_screen function is called from tty3270_install with
swapped arguments, the number of columns instead of rows and vice versa.
The number of rows is typically smaller than the number of columns which
makes the screen array too big but the individual cell arrays for the
lines too small. Creating lines longer than the number of rows will
clobber the memory after the end of the cell array.
The fix is simple, call tty3270_alloc_screen with the correct argument
order.

Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

qeth: avoid buffer overflow in snmp ioctl

2013-12-04T18:56:37+00:00

commit 6fb392b1a63ae36c31f62bc3fc8630b49d602b62 upstream.

Check user-defined length in snmp ioctl request and allow request
only if it fits into a qeth command buffer.

Signed-off-by: Ursula Braun 
Signed-off-by: Frank Blaschka 
Reviewed-by: Heiko Carstens 
Reported-by: Nico Golde 
Reported-by: Fabian Yamaguchi 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

SCSI: zfcp: fix schedule-inside-lock in scsi_device list loops

2013-08-29T16:47:39+00:00

commit 924dd584b198a58aa7cb3efefd8a03326550ce8f upstream.

BUG: sleeping function called from invalid context at kernel/workqueue.c:2752
in_atomic(): 1, irqs_disabled(): 1, pid: 360, name: zfcperp0.0.1700
CPU: 1 Not tainted 3.9.3+ #69
Process zfcperp0.0.1700 (pid: 360, task: 0000000075b7e080, ksp: 000000007476bc30)

Call Trace:
([<00000000001165de>] show_trace+0x106/0x154)
 [<00000000001166a0>] show_stack+0x74/0xf4
 [<00000000006ff646>] dump_stack+0xc6/0xd4
 [<000000000017f3a0>] __might_sleep+0x128/0x148
 [<000000000015ece8>] flush_work+0x54/0x1f8
 [<00000000001630de>] __cancel_work_timer+0xc6/0x128
 [<00000000005067ac>] scsi_device_dev_release_usercontext+0x164/0x23c
 [<0000000000161816>] execute_in_process_context+0x96/0xa8
 [<00000000004d33d8>] device_release+0x60/0xc0
 [<000000000048af48>] kobject_release+0xa8/0x1c4
 [<00000000004f4bf2>] __scsi_iterate_devices+0xfa/0x130
 [<000003ff801b307a>] zfcp_erp_strategy+0x4da/0x1014 [zfcp]
 [<000003ff801b3caa>] zfcp_erp_thread+0xf6/0x2b0 [zfcp]
 [<000000000016b75a>] kthread+0xf2/0xfc
 [<000000000070c9de>] kernel_thread_starter+0x6/0xc
 [<000000000070c9d8>] kernel_thread_starter+0x0/0xc

Apparently, the ref_count for some scsi_device drops down to zero,
triggering device removal through execute_in_process_context(), while
the lldd error recovery thread iterates through a scsi device list.
Unfortunately, execute_in_process_context() decides to immediately
execute that device removal function, instead of scheduling asynchronous
execution, since it detects process context and thinks it is safe to do
so. But almost all calls to shost_for_each_device() in our lldd are
inside spin_lock_irq, even in thread context. Obviously, schedule()
inside spin_lock_irq sections is a bad idea.

Change the lldd to use the proper iterator function,
__shost_for_each_device(), in combination with required locking.

Occurences that need to be changed include all calls in zfcp_erp.c,
since those might be executed in zfcp error recovery thread context
with a lock held.

Other occurences of shost_for_each_device() in zfcp_fsf.c do not
need to be changed (no process context, no surrounding locking).

The problem was introduced in Linux 2.6.37 by commit
b62a8d9b45b971a67a0f8413338c230e3117dff5
"[SCSI] zfcp: Use SCSI device data zfcp_scsi_dev instead of zfcp_unit".

Reported-by: Christian Borntraeger 
Signed-off-by: Martin Peschke 
Signed-off-by: Steffen Maier 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman

SCSI: zfcp: fix lock imbalance by reworking request queue locking

2013-08-29T16:47:39+00:00

commit d79ff142624e1be080ad8d09101f7004d79c36e1 upstream.

This patch adds wait_event_interruptible_lock_irq_timeout(), which is a
straight-forward descendant of wait_event_interruptible_timeout() and
wait_event_interruptible_lock_irq().

The zfcp driver used to call wait_event_interruptible_timeout()
in combination with some intricate and error-prone locking. Using
wait_event_interruptible_lock_irq_timeout() as a replacement
nicely cleans up that locking.

This rework removes a situation that resulted in a locking imbalance
in zfcp_qdio_sbal_get():

BUG: workqueue leaked lock or atomic: events/1/0xffffff00/10
    last function: zfcp_fc_wka_port_offline+0x0/0xa0 [zfcp]

It was introduced by commit c2af7545aaff3495d9bf9a7608c52f0af86fb194
"[SCSI] zfcp: Do not wait for SBALs on stopped queue", which had a new
code path related to ZFCP_STATUS_ADAPTER_QDIOUP that took an early exit
without a required lock being held. The problem occured when a
special, non-SCSI I/O request was being submitted in process context,
when the adapter's queues had been torn down. In this case the bug
surfaced when the Fibre Channel port connection for a well-known address
was closed during a concurrent adapter shut-down procedure, which is a
rare constellation.

This patch also fixes these warnings from the sparse tool (make C=1):

drivers/s390/scsi/zfcp_qdio.c:224:12: warning: context imbalance in
 'zfcp_qdio_sbal_check' - wrong count at exit
drivers/s390/scsi/zfcp_qdio.c:244:5: warning: context imbalance in
 'zfcp_qdio_sbal_get' - unexpected unlock

Last but not least, we get rid of that crappy lock-unlock-lock
sequence at the beginning of the critical section.

It is okay to call zfcp_erp_adapter_reopen() with req_q_lock held.

Reported-by: Mikulas Patocka 
Reported-by: Heiko Carstens 
Signed-off-by: Martin Peschke 
Signed-off-by: Steffen Maier 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman