linux-stable.git/drivers/scsi, branch v4.1.6

ipr: Fix invalid array indexing for HRRQ

2015-08-17T03:52:11+00:00

commit 3f1c0581310d5d94bd72740231507e763a6252a4 upstream.

Fixes another signed / unsigned array indexing bug in the ipr driver.
Currently, when hrrq_index wraps, it becomes a negative number. We
do the modulo, but still have a negative number, so we end up indexing
backwards in the array. Given where the hrrq array is located in memory,
we probably won't actually reference memory we don't own, but nonetheless
ipr is still looking at data within struct ipr_ioa_cfg and interpreting it as
struct ipr_hrr_queue data, so bad things could certainly happen.

Each ipr adapter has anywhere from 1 to 16 HRRQs. By default, we use 2 on new
adapters.  Let's take an example:

Assume ioa_cfg->hrrq_index=0x7fffffffe and ioa_cfg->hrrq_num=4:

The atomic_add_return will then return -1. We mod this with 3 and get -2, add
one and get -1 for an array index.

On adapters which support more than a single HRRQ, we dedicate HRRQ to adapter
initialization and error interrupts so that we can optimize the other queues
for fast path I/O. So all normal I/O uses HRRQ 1-15. So we want to spread the
I/O requests across those HRRQs.

With the default module parameter settings, this bug won't hit, only when
someone sets the ipr.number_of_msix parameter to a value larger than 3 is when
bad things start to happen.

Tested-by: Wen Xiong 
Reviewed-by: Wen Xiong 
Reviewed-by: Gabriel Krisman Bertazi 
Signed-off-by: Brian King 
Reviewed-by: Martin K. Petersen 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman

ipr: Fix incorrect trace indexing

2015-08-17T03:52:10+00:00

commit bb7c54339e6a10ecce5c4961adf5e75b3cf0af30 upstream.

When ipr's internal driver trace was changed to an atomic, a signed/unsigned
bug slipped in which results in us indexing backwards in our memory buffer
writing on memory that does not belong to us. This patch fixes this by removing
the modulo and instead just mask off the low bits.

Tested-by: Wen Xiong 
Reviewed-by: Wen Xiong 
Reviewed-by: Gabriel Krisman Bertazi 
Signed-off-by: Brian King 
Reviewed-by: Martin K. Petersen 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman

ipr: Fix locking for unit attention handling

2015-08-17T03:52:10+00:00

commit 36b8e180e1e929e00b351c3b72aab3147fc14116 upstream.

Make sure we have the host lock held when calling scsi_report_bus_reset. Fixes
a crash seen as the __devices list in the scsi host was changing as we were
iterating through it.

Reviewed-by: Wen Xiong 
Reviewed-by: Gabriel Krisman Bertazi 
Signed-off-by: Brian King 
Reviewed-by: Martin K. Petersen 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman

qla2xxx: kill sessions/log out initiator on RSCN and port down events

2015-08-10T19:21:59+00:00

commit b2032fd567326ad0b2d443bb6d96d2580ec670a5 upstream.

To fix some issues talking to ESX, this patch modifies the qla2xxx driver
so that it never logs into remote ports.  This has the side effect of
getting rid of the "rports" entirely, which means we never log out of
initiators and never tear down sessions when an initiator goes away.

This is mostly OK, except that we can run into trouble if we have
initiator A assigned FC address X:Y:Z by the fabric talking to us, and
then initiator A goes away.  Some time (could be a long time) later,
initiator B comes along and also gets FC address X:Y:Z (which is
available again, because initiator A is gone).  If initiator B starts
talking to us, then we'll still have the session for initiator A, and
since we look up incoming IO based on the FC address X:Y:Z, initiator B
will end up using ACLs for initiator A.

Fix this by:

 1. Handling RSCN events somewhat differently; instead of completely
    skipping the processing of fcports, we look through the list, and if
    an fcport disappears, we tell the target code the tear down the
    session and tell the HBA FW to release the N_Port handle.

 2. Handling "port down" events by flushing all of our sessions.  The
    firmware was already releasing the N_Port handle but we want the
    target code to drop all the sessions too.

Signed-off-by: Roland Dreier 
Signed-off-by: Alexei Potashnik 
Acked-by: Quinn Tran 
Signed-off-by: Himanshu Madhani 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

qla2xxx: fix command initialization in target mode.

2015-08-10T19:21:59+00:00

commit 9fce12540cb9f91e7f1f539a80b70f0b388bdae0 upstream.

Signed-off-by: Kanoj Sarcar 
Signed-off-by: Himanshu Madhani 
Reviewed-by: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

qla2xxx: Remove msleep in qlt_send_term_exchange

2015-08-10T19:21:59+00:00

commit 6bc85dd595a5438b50ec085668e53ef26058bb90 upstream.

Remove unnecessary msleep from qlt_send_term_exchange as it
adds latency of 250 msec while sending terminate exchange to
an aborted task.

Signed-off-by: Himanshu Madhani 
Signed-off-by: Giridhar Malavali 
Reviewed-by: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

qla2xxx: release request queue reservation.

2015-08-10T19:21:59+00:00

commit 810e30bc4658e9c069577bde52394a5af872803c upstream.

Request IOCB queue element(s) is reserved during
good path IO.  Under error condition such as unable
to allocate IOCB handle condition, the IOCB count
that was reserved is not released.

Signed-off-by: Quinn Tran 
Signed-off-by: Himanshu Madhani 
Reviewed-by: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

qla2xxx: Fix hardware lock/unlock issue causing kernel panic.

2015-08-10T19:21:59+00:00

commit ba9f6f64a0ff6b7ecaed72144c179061f8eca378 upstream.

[ Upstream commit ef86cb2059a14b4024c7320999ee58e938873032 ]

This patch fixes a kernel panic for qla2xxx Target core
Module driver introduced by a fix in the qla2xxx initiator code.

Commit ef86cb2 ("qla2xxx: Mark port lost when we receive an RSCN for it.")
introduced the regression for qla2xxx Target driver.

Stack trace will have following signature

 ---  ---
[ffff88081faa3cc8] _raw_spin_lock_irqsave at ffffffff815b1f03
[ffff88081faa3cd0] qlt_fc_port_deleted at ffffffffa096ccd0 [qla2xxx]
[ffff88081faa3d20] qla2x00_schedule_rport_del at ffffffffa0913831[qla2xxx]
[ffff88081faa3d50] qla2x00_mark_device_lost at ffffffffa09159c5[qla2xxx]
[ffff88081faa3db0] qla2x00_async_event at ffffffffa0938d59 [qla2xxx]
[ffff88081faa3e30] qla24xx_msix_default at ffffffffa093a326 [qla2xxx]
[ffff88081faa3e90] handle_irq_event_percpu at ffffffff810a7b8d
[ffff88081faa3ee0] handle_irq_event at ffffffff810a7d32
[ffff88081faa3f10] handle_edge_irq at ffffffff810ab6b9
[ffff88081faa3f30] handle_irq at ffffffff8100619c
[ffff88081faa3f70] do_IRQ at ffffffff815b4b1c
 ---  ---

Signed-off-by: Saurav Kashyap 
Signed-off-by: Himanshu Madhani 
Reviewed-by: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

st: null pointer dereference panic caused by use after kref_put by st_open

2015-08-10T19:21:54+00:00

commit e7ac6c6666bec0a354758a1298d3231e4a635362 upstream.

Two SLES11 SP3 servers encountered similar crashes simultaneously
following some kind of SAN/tape target issue:

...
qla2xxx [0000:81:00.0]-801c:3: Abort command issued nexus=3:0:2 --  1 2002.
qla2xxx [0000:81:00.0]-801c:3: Abort command issued nexus=3:0:2 --  1 2002.
qla2xxx [0000:81:00.0]-8009:3: DEVICE RESET ISSUED nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800c:3: do_reset failed for cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800f:3: DEVICE RESET FAILED: Task management failed nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-8009:3: TARGET RESET ISSUED nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800c:3: do_reset failed for cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800f:3: TARGET RESET FAILED: Task management failed nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-8012:3: BUS RESET ISSUED nexus=3:0:2.
qla2xxx [0000:81:00.0]-802b:3: BUS RESET SUCCEEDED nexus=3:0:2.
qla2xxx [0000:81:00.0]-505f:3: Link is operational (8 Gbps).
qla2xxx [0000:81:00.0]-8018:3: ADAPTER RESET ISSUED nexus=3:0:2.
qla2xxx [0000:81:00.0]-00af:3: Performing ISP error recovery - ha=ffff88bf04d18000.
 rport-3:0-0: blocked FC remote port time out: removing target and saving binding
qla2xxx [0000:81:00.0]-505f:3: Link is operational (8 Gbps).
qla2xxx [0000:81:00.0]-8017:3: ADAPTER RESET SUCCEEDED nexus=3:0:2.
 rport-2:0-0: blocked FC remote port time out: removing target and saving binding
sg_rq_end_io: device detached
BUG: unable to handle kernel NULL pointer dereference at 00000000000002a8
IP: [] __pm_runtime_idle+0x28/0x90
PGD 7e6586f067 PUD 7e5af06067 PMD 0 [1739975.390354] Oops: 0002 [#1] SMP
CPU 0
...
Supported: No, Proprietary modules are loaded [1739975.390463]
Pid: 27965, comm: ABCD Tainted: PF           X 3.0.101-0.29-default #1 HP ProLiant DL580 Gen8
RIP: 0010:[]  [] __pm_runtime_idle+0x28/0x90
RSP: 0018:ffff8839dc1e7c68  EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff883f0592fc00 RCX: 0000000000000090
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000138
RBP: 0000000000000138 R08: 0000000000000010 R09: ffffffff81bd39d0
R10: 00000000000009c0 R11: ffffffff81025790 R12: 0000000000000001
R13: ffff883022212b80 R14: 0000000000000004 R15: ffff883022212b80
FS:  00007f8e54560720(0000) GS:ffff88407f800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00000000000002a8 CR3: 0000007e6ced6000 CR4: 00000000001407f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process ABCD (pid: 27965, threadinfo ffff8839dc1e6000, task ffff883592e0c640)
Stack:
 ffff883f0592fc00 00000000fffffffa 0000000000000001 ffff883022212b80
 ffff883eff772400 ffffffffa03fa309 0000000000000000 0000000000000000
 ffffffffa04003a0 ffff883f063196c0 ffff887f0379a930 ffffffff8115ea1e
Call Trace:
 [] st_open+0x129/0x240 [st]
 [] chrdev_open+0x13e/0x200
 [] __dentry_open+0x198/0x310
 [] do_last+0x1f4/0x800
 [] path_openat+0xd9/0x420
 [] do_filp_open+0x4c/0xc0
 [] do_sys_open+0x17f/0x250
 [] system_call_fastpath+0x16/0x1b
 [<00007f8e4f617fd0>] 0x7f8e4f617fcf
Code: eb d3 90 48 83 ec 28 40 f6 c6 04 48 89 6c 24 08 4c 89 74 24 20 48 89 fd 48 89 1c 24 4c 89 64 24 10 41 89 f6 4c 89 6c 24 18 74 11  ff 8f 70 01 00 00 0f 94 c0 45 31 ed 84 c0 74 2b 4c 8d a5 a0
RIP  [] __pm_runtime_idle+0x28/0x90
 RSP 
CR2: 00000000000002a8

Analysis reveals the cause of the crash to be due to STp->device
being NULL. The pointer was NULLed via scsi_tape_put(STp) when it
calls scsi_tape_release(). In st_open() we jump to err_out after
scsi_block_when_processing_errors() completes and returns the
device as offline (sdev_state was SDEV_DEL):

1180 /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1181    module count. */
1182 static int st_open(struct inode *inode, struct file *filp)
1183 {
1184         int i, retval = (-EIO);
1185         int resumed = 0;
1186         struct scsi_tape *STp;
1187         struct st_partstat *STps;
1188         int dev = TAPE_NR(inode);
1189         char *name;
...
1217         if (scsi_autopm_get_device(STp->device) < 0) {
1218                 retval = -EIO;
1219                 goto err_out;
1220         }
1221         resumed = 1;
1222         if (!scsi_block_when_processing_errors(STp->device)) {
1223                 retval = (-ENXIO);
1224                 goto err_out;
1225         }
...
1264  err_out:
1265         normalize_buffer(STp->buffer);
1266         spin_lock(&st_use_lock);
1267         STp->in_use = 0;
1268         spin_unlock(&st_use_lock);
1269         scsi_tape_put(STp); <-- STp->device = 0 after this
1270         if (resumed)
1271                 scsi_autopm_put_device(STp->device);
1272         return retval;

The ref count for the struct scsi_tape had already been reduced
to 1 when the .remove method of the st module had been called.
The kref_put() in scsi_tape_put() caused scsi_tape_release()
to be called:

0266 static void scsi_tape_put(struct scsi_tape *STp)
0267 {
0268         struct scsi_device *sdev = STp->device;
0269
0270         mutex_lock(&st_ref_mutex);
0271         kref_put(&STp->kref, scsi_tape_release); <-- calls this
0272         scsi_device_put(sdev);
0273         mutex_unlock(&st_ref_mutex);
0274 }

In scsi_tape_release() the struct scsi_device in the struct
scsi_tape gets set to NULL:

4273 static void scsi_tape_release(struct kref *kref)
4274 {
4275         struct scsi_tape *tpnt = to_scsi_tape(kref);
4276         struct gendisk *disk = tpnt->disk;
4277
4278         tpnt->device = NULL; <<<---- where the dev is nulled
4279
4280         if (tpnt->buffer) {
4281                 normalize_buffer(tpnt->buffer);
4282                 kfree(tpnt->buffer->reserved_pages);
4283                 kfree(tpnt->buffer);
4284         }
4285
4286         disk->private_data = NULL;
4287         put_disk(disk);
4288         kfree(tpnt);
4289         return;
4290 }

Although the problem was reported on SLES11.3 the problem appears
in linux-next as well.

The crash is fixed by reordering the code so we no longer access
the struct scsi_tape after the kref_put() is done on it in st_open().

Signed-off-by: Shane Seymour 
Signed-off-by: Darren Lavender 
Reviewed-by: Johannes Thumshirn 
Acked-by: Kai Mäkisara 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman

scsi: fix memory leak with scsi-mq

2015-08-10T19:21:54+00:00

commit 0c958ecc69c277b25f38f72bc6d18ab145e8167c upstream.

Fix a memory leak with scsi-mq triggered by commands with large data
transfer length.

__sg_alloc_table() sets both table->nents and table->orig_nents to the
same value.  When the scatterlist is DMA-mapped, table->nents is
overwritten with the (possibly smaller) size of the DMA-mapped
scatterlist, while table->orig_nents retains the original size of the
allocated scatterlist.  scsi_free_sgtable() should therefore check
orig_nents instead of nents, and all code that initializes sdb->table
without calling __sg_alloc_table() should set both nents and orig_nents.

Fixes: d285203cf647 ("scsi: add support for a blk-mq based I/O path.")
Signed-off-by: Tony Battersby 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Ewan D. Milne 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman