linux-toradex.git/drivers/scsi/scsi_scan.c, branch v4.13-rc5 Linux kernel for Apalis and Colibri modules Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi 2017-07-06T19:10:33+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-07-06T19:10:33+00:00 90311148415ab23f5767fbb577a012d4405f12e5 Pull SCSI updates from James Bottomley: "This is mostly updates of the usual suspects: lpfc, qla2xxx, bnx2fc, qedf, hpsa, hisi_sas, smartpqi, cxlflash, aacraid, csiostor along with a host of minor and miscellaneous changes" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (276 commits) qla2xxx: Fix NVMe entry_type for iocb packet on BE system scsi: qla2xxx: avoid unused-function warning scsi: snic: fix a couple of spelling mistakes/typos scsi: qla2xxx: fix a bunch of typos and spelling mistakes scsi: lpfc: don't double count abort errors scsi: lpfc: spin_lock_irq() is not nestable scsi: hisi_sas: optimise DMA slot memory scsi: ibmvfc: constify dev_pm_ops structures. scsi: ibmvscsi: constify dev_pm_ops structures. scsi: cxlflash: Update debug prints in reset handlers scsi: cxlflash: Update send_tmf() parameters scsi: cxlflash: Avoid double free of character device scsi: Add STARGET_CREATED_REMOVE state to scsi_target_state scsi: ses: do not add a device to an enclosure if enclosure_add_links() fails. scsi: ufs: flush eh_work when eh_work scheduled. scsi: qla2xxx: Protect access to qpair members with qpair->qp_lock scsi: sun_esp: fix device reference leaks scsi: fnic: changing queue command to return result DID_IMM_RETRY when rport is init scsi: fnic: correct speed display and add support for 25,40 and 100G scsi: fnic: added timestamp reporting in fnic debug stats ... 
Pull SCSI updates from James Bottomley:
 "This is mostly updates of the usual suspects: lpfc, qla2xxx, bnx2fc,
  qedf, hpsa, hisi_sas, smartpqi, cxlflash, aacraid, csiostor along with
  a host of minor and miscellaneous changes"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (276 commits)
  qla2xxx: Fix NVMe entry_type for iocb packet on BE system
  scsi: qla2xxx: avoid unused-function warning
  scsi: snic: fix a couple of spelling mistakes/typos
  scsi: qla2xxx: fix a bunch of typos and spelling mistakes
  scsi: lpfc: don't double count abort errors
  scsi: lpfc: spin_lock_irq() is not nestable
  scsi: hisi_sas: optimise DMA slot memory
  scsi: ibmvfc: constify dev_pm_ops structures.
  scsi: ibmvscsi: constify dev_pm_ops structures.
  scsi: cxlflash: Update debug prints in reset handlers
  scsi: cxlflash: Update send_tmf() parameters
  scsi: cxlflash: Avoid double free of character device
  scsi: Add STARGET_CREATED_REMOVE state to scsi_target_state
  scsi: ses: do not add a device to an enclosure if enclosure_add_links() fails.
  scsi: ufs: flush eh_work when eh_work scheduled.
  scsi: qla2xxx: Protect access to qpair members with qpair->qp_lock
  scsi: sun_esp: fix device reference leaks
  scsi: fnic: changing queue command to return result DID_IMM_RETRY when rport is init
  scsi: fnic: correct speed display and add support for 25,40 and 100G
  scsi: fnic: added timestamp reporting in fnic debug stats
  ...
scsi: Add STARGET_CREATED_REMOVE state to scsi_target_state 2017-07-01T20:54:44+00:00 Ewan D. Milne emilne@redhat.com 2017-06-27T18:55:58+00:00 f9279c968c257ee39b0d7bd2571a4d231a67bcc1 The addition of the STARGET_REMOVE state had the side effect of introducing a race condition that can cause a crash. scsi_target_reap_ref_release() checks the starget->state to see if it still in STARGET_CREATED, and if so, skips calling transport_remove_device() and device_del(), because the starget->state is only set to STARGET_RUNNING after scsi_target_add() has called device_add() and transport_add_device(). However, if an rport loss occurs while a target is being scanned, it can happen that scsi_remove_target() will be called while the starget is still in the STARGET_CREATED state. In this case, the starget->state will be set to STARGET_REMOVE, and as a result, scsi_target_reap_ref_release() will take the wrong path. The end result is a panic: [ 1255.356653] Oops: 0000 [#1] SMP [ 1255.360154] Modules linked in: x86_pkg_temp_thermal kvm_intel kvm irqbypass crc32c_intel ghash_clmulni_i [ 1255.393234] CPU: 5 PID: 149 Comm: kworker/u96:4 Tainted: G W 4.11.0+ #8 [ 1255.401879] Hardware name: Dell Inc. PowerEdge R320/08VT7V, BIOS 2.0.22 11/19/2013 [ 1255.410327] Workqueue: scsi_wq_6 fc_scsi_scan_rport [scsi_transport_fc] [ 1255.417720] task: ffff88060ca8c8c0 task.stack: ffffc900048a8000 [ 1255.424331] RIP: 0010:kernfs_find_ns+0x13/0xc0 [ 1255.429287] RSP: 0018:ffffc900048abbf0 EFLAGS: 00010246 [ 1255.435123] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 1255.443083] RDX: 0000000000000000 RSI: ffffffff8188d659 RDI: 0000000000000000 [ 1255.451043] RBP: ffffc900048abc10 R08: 0000000000000000 R09: 0000012433fe0025 [ 1255.459005] R10: 0000000025e5a4b5 R11: 0000000025e5a4b5 R12: ffffffff8188d659 [ 1255.466972] R13: 0000000000000000 R14: ffff8805f55e5088 R15: 0000000000000000 [ 1255.474931] FS: 0000000000000000(0000) GS:ffff880616b40000(0000) knlGS:0000000000000000 [ 1255.483959] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1255.490370] CR2: 0000000000000068 CR3: 0000000001c09000 CR4: 00000000000406e0 [ 1255.498332] Call Trace: [ 1255.501058] kernfs_find_and_get_ns+0x31/0x60 [ 1255.505916] sysfs_unmerge_group+0x1d/0x60 [ 1255.510498] dpm_sysfs_remove+0x22/0x60 [ 1255.514783] device_del+0xf4/0x2e0 [ 1255.518577] ? device_remove_file+0x19/0x20 [ 1255.523241] attribute_container_class_device_del+0x1a/0x20 [ 1255.529457] transport_remove_classdev+0x4e/0x60 [ 1255.534607] ? transport_add_class_device+0x40/0x40 [ 1255.540046] attribute_container_device_trigger+0xb0/0xc0 [ 1255.546069] transport_remove_device+0x15/0x20 [ 1255.551025] scsi_target_reap_ref_release+0x25/0x40 [ 1255.556467] scsi_target_reap+0x2e/0x40 [ 1255.560744] __scsi_scan_target+0xaa/0x5b0 [ 1255.565312] scsi_scan_target+0xec/0x100 [ 1255.569689] fc_scsi_scan_rport+0xb1/0xc0 [scsi_transport_fc] [ 1255.576099] process_one_work+0x14b/0x390 [ 1255.580569] worker_thread+0x4b/0x390 [ 1255.584651] kthread+0x109/0x140 [ 1255.588251] ? rescuer_thread+0x330/0x330 [ 1255.592730] ? kthread_park+0x60/0x60 [ 1255.596815] ret_from_fork+0x29/0x40 [ 1255.600801] Code: 24 08 48 83 42 40 01 5b 41 5c 5d c3 66 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 [ 1255.621876] RIP: kernfs_find_ns+0x13/0xc0 RSP: ffffc900048abbf0 [ 1255.628479] CR2: 0000000000000068 [ 1255.632756] ---[ end trace 34a69ba0477d036f ]--- Fix this by adding another scsi_target state STARGET_CREATED_REMOVE to distinguish this case. Fixes: f05795d3d771 ("scsi: Add intermediate STARGET_REMOVE state to scsi_target_state") Reported-by: David Jeffery <djeffery@redhat.com> Signed-off-by: Ewan D. Milne <emilne@redhat.com> Cc: <stable@vger.kernel.org> Reviewed-by: Laurence Oberman <loberman@redhat.com> Tested-by: Laurence Oberman <loberman@redhat.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
The addition of the STARGET_REMOVE state had the side effect of
introducing a race condition that can cause a crash.

scsi_target_reap_ref_release() checks the starget->state to
see if it still in STARGET_CREATED, and if so, skips calling
transport_remove_device() and device_del(), because the starget->state
is only set to STARGET_RUNNING after scsi_target_add() has called
device_add() and transport_add_device().

However, if an rport loss occurs while a target is being scanned,
it can happen that scsi_remove_target() will be called while the
starget is still in the STARGET_CREATED state.  In this case, the
starget->state will be set to STARGET_REMOVE, and as a result,
scsi_target_reap_ref_release() will take the wrong path.  The end
result is a panic:

[ 1255.356653] Oops: 0000 [#1] SMP
[ 1255.360154] Modules linked in: x86_pkg_temp_thermal kvm_intel kvm irqbypass crc32c_intel ghash_clmulni_i
[ 1255.393234] CPU: 5 PID: 149 Comm: kworker/u96:4 Tainted: G        W       4.11.0+ #8
[ 1255.401879] Hardware name: Dell Inc. PowerEdge R320/08VT7V, BIOS 2.0.22 11/19/2013
[ 1255.410327] Workqueue: scsi_wq_6 fc_scsi_scan_rport [scsi_transport_fc]
[ 1255.417720] task: ffff88060ca8c8c0 task.stack: ffffc900048a8000
[ 1255.424331] RIP: 0010:kernfs_find_ns+0x13/0xc0
[ 1255.429287] RSP: 0018:ffffc900048abbf0 EFLAGS: 00010246
[ 1255.435123] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[ 1255.443083] RDX: 0000000000000000 RSI: ffffffff8188d659 RDI: 0000000000000000
[ 1255.451043] RBP: ffffc900048abc10 R08: 0000000000000000 R09: 0000012433fe0025
[ 1255.459005] R10: 0000000025e5a4b5 R11: 0000000025e5a4b5 R12: ffffffff8188d659
[ 1255.466972] R13: 0000000000000000 R14: ffff8805f55e5088 R15: 0000000000000000
[ 1255.474931] FS:  0000000000000000(0000) GS:ffff880616b40000(0000) knlGS:0000000000000000
[ 1255.483959] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1255.490370] CR2: 0000000000000068 CR3: 0000000001c09000 CR4: 00000000000406e0
[ 1255.498332] Call Trace:
[ 1255.501058]  kernfs_find_and_get_ns+0x31/0x60
[ 1255.505916]  sysfs_unmerge_group+0x1d/0x60
[ 1255.510498]  dpm_sysfs_remove+0x22/0x60
[ 1255.514783]  device_del+0xf4/0x2e0
[ 1255.518577]  ? device_remove_file+0x19/0x20
[ 1255.523241]  attribute_container_class_device_del+0x1a/0x20
[ 1255.529457]  transport_remove_classdev+0x4e/0x60
[ 1255.534607]  ? transport_add_class_device+0x40/0x40
[ 1255.540046]  attribute_container_device_trigger+0xb0/0xc0
[ 1255.546069]  transport_remove_device+0x15/0x20
[ 1255.551025]  scsi_target_reap_ref_release+0x25/0x40
[ 1255.556467]  scsi_target_reap+0x2e/0x40
[ 1255.560744]  __scsi_scan_target+0xaa/0x5b0
[ 1255.565312]  scsi_scan_target+0xec/0x100
[ 1255.569689]  fc_scsi_scan_rport+0xb1/0xc0 [scsi_transport_fc]
[ 1255.576099]  process_one_work+0x14b/0x390
[ 1255.580569]  worker_thread+0x4b/0x390
[ 1255.584651]  kthread+0x109/0x140
[ 1255.588251]  ? rescuer_thread+0x330/0x330
[ 1255.592730]  ? kthread_park+0x60/0x60
[ 1255.596815]  ret_from_fork+0x29/0x40
[ 1255.600801] Code: 24 08 48 83 42 40 01 5b 41 5c 5d c3 66 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90
[ 1255.621876] RIP: kernfs_find_ns+0x13/0xc0 RSP: ffffc900048abbf0
[ 1255.628479] CR2: 0000000000000068
[ 1255.632756] ---[ end trace 34a69ba0477d036f ]---

Fix this by adding another scsi_target state STARGET_CREATED_REMOVE
to distinguish this case.

Fixes: f05795d3d771 ("scsi: Add intermediate STARGET_REMOVE state to scsi_target_state")
Reported-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi: remove various unused blist flags 2017-06-26T16:44:27+00:00 Christoph Hellwig hch@lst.de 2017-06-19T12:27:23+00:00 496c91bbc9109ff99907d2a94fccb7d8d4349010 Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi: Protect SCSI device state changes with a mutex 2017-06-13T00:55:59+00:00 Bart Van Assche bart.vanassche@sandisk.com 2017-06-02T21:21:55+00:00 0db6ca8a5e1ea585795db3643ec7d50fc8cb1aff Serializing SCSI device state changes avoids that two state changes can occur concurrently, e.g. the state changes in scsi_target_block() and __scsi_remove_device(). This serialization is essential to make patch "Make __scsi_remove_device go straight from BLOCKED to DEL" work reliably. Enable this mechanism for all scsi_target_*block() callers but not for the scsi_internal_device_unblock() calls from the mpt3sas driver because that driver can call scsi_internal_device_unblock() from atomic context. Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
Serializing SCSI device state changes avoids that two state changes can
occur concurrently, e.g. the state changes in scsi_target_block() and
__scsi_remove_device(). This serialization is essential to make patch
"Make __scsi_remove_device go straight from BLOCKED to DEL" work
reliably.

Enable this mechanism for all scsi_target_*block() callers but not for
the scsi_internal_device_unblock() calls from the mpt3sas driver because
that driver can call scsi_internal_device_unblock() from atomic context.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi: fix some kernel-doc markups 2017-05-16T11:44:15+00:00 Mauro Carvalho Chehab mchehab@s-opensource.com 2017-05-12T13:04:14+00:00 739aca06a2d2d2c3435c526bca8b27a6c9a8c3e7 Sphinx is very pedantic with regards to ident/spacing. Fix some kernel-doc markups in order to solve those errors/warnings: ./drivers/scsi/scsicam.c:121: WARNING: Inline emphasis start-string without end-string. ./drivers/scsi/scsicam.c:121: WARNING: Inline emphasis start-string without end-string. ./drivers/scsi/scsicam.c:121: WARNING: Inline emphasis start-string without end-string. ./drivers/scsi/scsi_scan.c:1056: ERROR: Unexpected indentation. ./drivers/scsi/scsi_scan.c:1057: WARNING: Block quote ends without a blank line; unexpected unindent. ./drivers/scsi/scsi_transport_fc.c:2918: ERROR: Unexpected indentation. ./drivers/scsi/scsi_transport_fc.c:2921: WARNING: Block quote ends without a blank line; unexpected unindent. ./drivers/scsi/scsi_transport_fc.c:2922: WARNING: Enumerated list ends without a blank line; unexpected unindent. No functional changes. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> 
Sphinx is very pedantic with regards to ident/spacing.
Fix some kernel-doc markups in order to solve those
errors/warnings:

./drivers/scsi/scsicam.c:121: WARNING: Inline emphasis start-string without end-string.
./drivers/scsi/scsicam.c:121: WARNING: Inline emphasis start-string without end-string.
./drivers/scsi/scsicam.c:121: WARNING: Inline emphasis start-string without end-string.
./drivers/scsi/scsi_scan.c:1056: ERROR: Unexpected indentation.
./drivers/scsi/scsi_scan.c:1057: WARNING: Block quote ends without a blank line; unexpected unindent.
./drivers/scsi/scsi_transport_fc.c:2918: ERROR: Unexpected indentation.
./drivers/scsi/scsi_transport_fc.c:2921: WARNING: Block quote ends without a blank line; unexpected unindent.
./drivers/scsi/scsi_transport_fc.c:2922: WARNING: Enumerated list ends without a blank line; unexpected unindent.

No functional changes.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
scsi: Remove one useless stack variable 2016-10-11T22:02:09+00:00 Ming Lei tom.leiming@gmail.com 2016-10-10T15:25:33+00:00 03eb6b8d314e89e94d4f79ee3d3e6596a75bc857 The local variable of 'devname' in scsi_report_lun_scan() isn't used any more, so remove it. Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
The local variable of 'devname' in scsi_report_lun_scan() isn't used any
more, so remove it.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi: Fix use-after-free 2016-10-11T22:00:20+00:00 Ming Lei tom.leiming@gmail.com 2016-10-09T05:23:27+00:00 bcd8f2e94808fcddf6ef3af5f060a36820dcc432 This patch fixes one use-after-free report[1] by KASAN. In __scsi_scan_target(), when a type 31 device is probed, SCSI_SCAN_TARGET_PRESENT is returned and the target will be scanned again. Inside the following scsi_report_lun_scan(), one new scsi_device instance is allocated, and scsi_probe_and_add_lun() is called again to probe the target and still see type 31 device, finally __scsi_remove_device() is called to remove & free the device at the end of scsi_probe_and_add_lun(), so cause use-after-free in scsi_report_lun_scan(). And the following SCSI log can be observed: scsi 0:0:2:0: scsi scan: INQUIRY pass 1 length 36 scsi 0:0:2:0: scsi scan: INQUIRY successful with code 0x0 scsi 0:0:2:0: scsi scan: peripheral device type of 31, no device added scsi 0:0:2:0: scsi scan: Sending REPORT LUNS to (try 0) scsi 0:0:2:0: scsi scan: REPORT LUNS successful (try 0) result 0x0 scsi 0:0:2:0: scsi scan: REPORT LUN scan scsi 0:0:2:0: scsi scan: INQUIRY pass 1 length 36 scsi 0:0:2:0: scsi scan: INQUIRY successful with code 0x0 scsi 0:0:2:0: scsi scan: peripheral device type of 31, no device added BUG: KASAN: use-after-free in __scsi_scan_target+0xbf8/0xe40 at addr ffff88007b44a104 This patch fixes the issue by moving the putting reference at the end of scsi_report_lun_scan(). [1] KASAN report ================================================================== [ 3.274597] PM: Adding info for serio:serio1 [ 3.275127] BUG: KASAN: use-after-free in __scsi_scan_target+0xd87/0xdf0 at addr ffff880254d8c304 [ 3.275653] Read of size 4 by task kworker/u10:0/27 [ 3.275903] CPU: 3 PID: 27 Comm: kworker/u10:0 Not tainted 4.8.0 #2121 [ 3.276258] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 [ 3.276797] Workqueue: events_unbound async_run_entry_fn [ 3.277083] ffff880254d8c380 ffff880259a37870 ffffffff94bbc6c1 ffff880078402d80 [ 3.277532] ffff880254d8bb80 ffff880259a37898 ffffffff9459fec1 ffff880259a37930 [ 3.277989] ffff880254d8bb80 ffff880078402d80 ffff880259a37920 ffffffff945a0165 [ 3.278436] Call Trace: [ 3.278528] [<ffffffff94bbc6c1>] dump_stack+0x65/0x84 [ 3.278797] [<ffffffff9459fec1>] kasan_object_err+0x21/0x70 [ 3.279063] device: 'psaux': device_add [ 3.279616] [<ffffffff945a0165>] kasan_report_error+0x205/0x500 [ 3.279651] PM: Adding info for No Bus:psaux [ 3.280202] [<ffffffff944ecd22>] ? kfree_const+0x22/0x30 [ 3.280486] [<ffffffff94bc2dc9>] ? kobject_release+0x119/0x370 [ 3.280805] [<ffffffff945a0543>] __asan_report_load4_noabort+0x43/0x50 [ 3.281170] [<ffffffff9507e1f7>] ? __scsi_scan_target+0xd87/0xdf0 [ 3.281506] [<ffffffff9507e1f7>] __scsi_scan_target+0xd87/0xdf0 [ 3.281848] [<ffffffff9507d470>] ? scsi_add_device+0x30/0x30 [ 3.282156] [<ffffffff94f7f660>] ? pm_runtime_autosuspend_expiration+0x60/0x60 [ 3.282570] [<ffffffff956ddb07>] ? _raw_spin_lock+0x17/0x40 [ 3.282880] [<ffffffff9507e505>] scsi_scan_channel+0x105/0x160 [ 3.283200] [<ffffffff9507e8a2>] scsi_scan_host_selected+0x212/0x2f0 [ 3.283563] [<ffffffff9507eb3c>] do_scsi_scan_host+0x1bc/0x250 [ 3.283882] [<ffffffff9507efc1>] do_scan_async+0x41/0x450 [ 3.284173] [<ffffffff941c1fee>] async_run_entry_fn+0xfe/0x610 [ 3.284492] [<ffffffff941a8954>] ? pwq_dec_nr_in_flight+0x124/0x2a0 [ 3.284876] [<ffffffff941d1770>] ? preempt_count_add+0x130/0x160 [ 3.285207] [<ffffffff941a9a84>] process_one_work+0x544/0x12d0 [ 3.285526] [<ffffffff941aa8e9>] worker_thread+0xd9/0x12f0 [ 3.285844] [<ffffffff941aa810>] ? process_one_work+0x12d0/0x12d0 [ 3.286182] [<ffffffff941bb365>] kthread+0x1c5/0x260 [ 3.286443] [<ffffffff940855cd>] ? __switch_to+0x88d/0x1430 [ 3.286745] [<ffffffff941bb1a0>] ? kthread_worker_fn+0x5a0/0x5a0 [ 3.287085] [<ffffffff956dde9f>] ret_from_fork+0x1f/0x40 [ 3.287368] [<ffffffff941bb1a0>] ? kthread_worker_fn+0x5a0/0x5a0 [ 3.287697] Object at ffff880254d8bb80, in cache kmalloc-2048 size: 2048 [ 3.288064] Allocated: [ 3.288147] PID = 27 [ 3.288218] [<ffffffff940b27ab>] save_stack_trace+0x2b/0x50 [ 3.288531] [<ffffffff9459f246>] save_stack+0x46/0xd0 [ 3.288806] [<ffffffff9459f4bd>] kasan_kmalloc+0xad/0xe0 [ 3.289098] [<ffffffff9459c07e>] __kmalloc+0x13e/0x250 [ 3.289378] [<ffffffff95078e5a>] scsi_alloc_sdev+0xea/0xcf0 [ 3.289701] [<ffffffff9507de76>] __scsi_scan_target+0xa06/0xdf0 [ 3.290034] [<ffffffff9507e505>] scsi_scan_channel+0x105/0x160 [ 3.290362] [<ffffffff9507e8a2>] scsi_scan_host_selected+0x212/0x2f0 [ 3.290724] [<ffffffff9507eb3c>] do_scsi_scan_host+0x1bc/0x250 [ 3.291055] [<ffffffff9507efc1>] do_scan_async+0x41/0x450 [ 3.291354] [<ffffffff941c1fee>] async_run_entry_fn+0xfe/0x610 [ 3.291695] [<ffffffff941a9a84>] process_one_work+0x544/0x12d0 [ 3.292022] [<ffffffff941aa8e9>] worker_thread+0xd9/0x12f0 [ 3.292325] [<ffffffff941bb365>] kthread+0x1c5/0x260 [ 3.292594] [<ffffffff956dde9f>] ret_from_fork+0x1f/0x40 [ 3.292886] Freed: [ 3.292945] PID = 27 [ 3.293016] [<ffffffff940b27ab>] save_stack_trace+0x2b/0x50 [ 3.293327] [<ffffffff9459f246>] save_stack+0x46/0xd0 [ 3.293600] [<ffffffff9459fa61>] kasan_slab_free+0x71/0xb0 [ 3.293916] [<ffffffff9459bac2>] kfree+0xa2/0x1f0 [ 3.294168] [<ffffffff9508158a>] scsi_device_dev_release_usercontext+0x50a/0x730 [ 3.294598] [<ffffffff941ace9a>] execute_in_process_context+0xda/0x130 [ 3.294974] [<ffffffff9508107c>] scsi_device_dev_release+0x1c/0x20 [ 3.295322] [<ffffffff94f566f6>] device_release+0x76/0x1e0 [ 3.295626] [<ffffffff94bc2db7>] kobject_release+0x107/0x370 [ 3.295942] [<ffffffff94bc29ce>] kobject_put+0x4e/0xa0 [ 3.296222] [<ffffffff94f56e17>] put_device+0x17/0x20 [ 3.296497] [<ffffffff9505201c>] scsi_device_put+0x7c/0xa0 [ 3.296801] [<ffffffff9507e1bc>] __scsi_scan_target+0xd4c/0xdf0 [ 3.297132] [<ffffffff9507e505>] scsi_scan_channel+0x105/0x160 [ 3.297458] [<ffffffff9507e8a2>] scsi_scan_host_selected+0x212/0x2f0 [ 3.297829] [<ffffffff9507eb3c>] do_scsi_scan_host+0x1bc/0x250 [ 3.298156] [<ffffffff9507efc1>] do_scan_async+0x41/0x450 [ 3.298453] [<ffffffff941c1fee>] async_run_entry_fn+0xfe/0x610 [ 3.298777] [<ffffffff941a9a84>] process_one_work+0x544/0x12d0 [ 3.299105] [<ffffffff941aa8e9>] worker_thread+0xd9/0x12f0 [ 3.299408] [<ffffffff941bb365>] kthread+0x1c5/0x260 [ 3.299676] [<ffffffff956dde9f>] ret_from_fork+0x1f/0x40 [ 3.299967] Memory state around the buggy address: [ 3.300209] ffff880254d8c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 3.300608] ffff880254d8c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 3.300986] >ffff880254d8c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 3.301408] ^ [ 3.301550] ffff880254d8c380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 3.301987] ffff880254d8c400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 3.302396] ================================================================== Cc: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org Signed-off-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
This patch fixes one use-after-free report[1] by KASAN.

In __scsi_scan_target(), when a type 31 device is probed,
SCSI_SCAN_TARGET_PRESENT is returned and the target will be scanned
again.

Inside the following scsi_report_lun_scan(), one new scsi_device
instance is allocated, and scsi_probe_and_add_lun() is called again to
probe the target and still see type 31 device, finally
__scsi_remove_device() is called to remove & free the device at the end
of scsi_probe_and_add_lun(), so cause use-after-free in
scsi_report_lun_scan().

And the following SCSI log can be observed:

	scsi 0:0:2:0: scsi scan: INQUIRY pass 1 length 36
	scsi 0:0:2:0: scsi scan: INQUIRY successful with code 0x0
	scsi 0:0:2:0: scsi scan: peripheral device type of 31, no device added
	scsi 0:0:2:0: scsi scan: Sending REPORT LUNS to (try 0)
	scsi 0:0:2:0: scsi scan: REPORT LUNS successful (try 0) result 0x0
	scsi 0:0:2:0: scsi scan: REPORT LUN scan
	scsi 0:0:2:0: scsi scan: INQUIRY pass 1 length 36
	scsi 0:0:2:0: scsi scan: INQUIRY successful with code 0x0
	scsi 0:0:2:0: scsi scan: peripheral device type of 31, no device added
	BUG: KASAN: use-after-free in __scsi_scan_target+0xbf8/0xe40 at addr ffff88007b44a104

This patch fixes the issue by moving the putting reference at
the end of scsi_report_lun_scan().

[1] KASAN report
==================================================================
[    3.274597] PM: Adding info for serio:serio1
[    3.275127] BUG: KASAN: use-after-free in __scsi_scan_target+0xd87/0xdf0 at addr ffff880254d8c304
[    3.275653] Read of size 4 by task kworker/u10:0/27
[    3.275903] CPU: 3 PID: 27 Comm: kworker/u10:0 Not tainted 4.8.0 #2121
[    3.276258] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
[    3.276797] Workqueue: events_unbound async_run_entry_fn
[    3.277083]  ffff880254d8c380 ffff880259a37870 ffffffff94bbc6c1 ffff880078402d80
[    3.277532]  ffff880254d8bb80 ffff880259a37898 ffffffff9459fec1 ffff880259a37930
[    3.277989]  ffff880254d8bb80 ffff880078402d80 ffff880259a37920 ffffffff945a0165
[    3.278436] Call Trace:
[    3.278528]  [<ffffffff94bbc6c1>] dump_stack+0x65/0x84
[    3.278797]  [<ffffffff9459fec1>] kasan_object_err+0x21/0x70
[    3.279063] device: 'psaux': device_add
[    3.279616]  [<ffffffff945a0165>] kasan_report_error+0x205/0x500
[    3.279651] PM: Adding info for No Bus:psaux
[    3.280202]  [<ffffffff944ecd22>] ? kfree_const+0x22/0x30
[    3.280486]  [<ffffffff94bc2dc9>] ? kobject_release+0x119/0x370
[    3.280805]  [<ffffffff945a0543>] __asan_report_load4_noabort+0x43/0x50
[    3.281170]  [<ffffffff9507e1f7>] ? __scsi_scan_target+0xd87/0xdf0
[    3.281506]  [<ffffffff9507e1f7>] __scsi_scan_target+0xd87/0xdf0
[    3.281848]  [<ffffffff9507d470>] ? scsi_add_device+0x30/0x30
[    3.282156]  [<ffffffff94f7f660>] ? pm_runtime_autosuspend_expiration+0x60/0x60
[    3.282570]  [<ffffffff956ddb07>] ? _raw_spin_lock+0x17/0x40
[    3.282880]  [<ffffffff9507e505>] scsi_scan_channel+0x105/0x160
[    3.283200]  [<ffffffff9507e8a2>] scsi_scan_host_selected+0x212/0x2f0
[    3.283563]  [<ffffffff9507eb3c>] do_scsi_scan_host+0x1bc/0x250
[    3.283882]  [<ffffffff9507efc1>] do_scan_async+0x41/0x450
[    3.284173]  [<ffffffff941c1fee>] async_run_entry_fn+0xfe/0x610
[    3.284492]  [<ffffffff941a8954>] ? pwq_dec_nr_in_flight+0x124/0x2a0
[    3.284876]  [<ffffffff941d1770>] ? preempt_count_add+0x130/0x160
[    3.285207]  [<ffffffff941a9a84>] process_one_work+0x544/0x12d0
[    3.285526]  [<ffffffff941aa8e9>] worker_thread+0xd9/0x12f0
[    3.285844]  [<ffffffff941aa810>] ? process_one_work+0x12d0/0x12d0
[    3.286182]  [<ffffffff941bb365>] kthread+0x1c5/0x260
[    3.286443]  [<ffffffff940855cd>] ? __switch_to+0x88d/0x1430
[    3.286745]  [<ffffffff941bb1a0>] ? kthread_worker_fn+0x5a0/0x5a0
[    3.287085]  [<ffffffff956dde9f>] ret_from_fork+0x1f/0x40
[    3.287368]  [<ffffffff941bb1a0>] ? kthread_worker_fn+0x5a0/0x5a0
[    3.287697] Object at ffff880254d8bb80, in cache kmalloc-2048 size: 2048
[    3.288064] Allocated:
[    3.288147] PID = 27
[    3.288218]  [<ffffffff940b27ab>] save_stack_trace+0x2b/0x50
[    3.288531]  [<ffffffff9459f246>] save_stack+0x46/0xd0
[    3.288806]  [<ffffffff9459f4bd>] kasan_kmalloc+0xad/0xe0
[    3.289098]  [<ffffffff9459c07e>] __kmalloc+0x13e/0x250
[    3.289378]  [<ffffffff95078e5a>] scsi_alloc_sdev+0xea/0xcf0
[    3.289701]  [<ffffffff9507de76>] __scsi_scan_target+0xa06/0xdf0
[    3.290034]  [<ffffffff9507e505>] scsi_scan_channel+0x105/0x160
[    3.290362]  [<ffffffff9507e8a2>] scsi_scan_host_selected+0x212/0x2f0
[    3.290724]  [<ffffffff9507eb3c>] do_scsi_scan_host+0x1bc/0x250
[    3.291055]  [<ffffffff9507efc1>] do_scan_async+0x41/0x450
[    3.291354]  [<ffffffff941c1fee>] async_run_entry_fn+0xfe/0x610
[    3.291695]  [<ffffffff941a9a84>] process_one_work+0x544/0x12d0
[    3.292022]  [<ffffffff941aa8e9>] worker_thread+0xd9/0x12f0
[    3.292325]  [<ffffffff941bb365>] kthread+0x1c5/0x260
[    3.292594]  [<ffffffff956dde9f>] ret_from_fork+0x1f/0x40
[    3.292886] Freed:
[    3.292945] PID = 27
[    3.293016]  [<ffffffff940b27ab>] save_stack_trace+0x2b/0x50
[    3.293327]  [<ffffffff9459f246>] save_stack+0x46/0xd0
[    3.293600]  [<ffffffff9459fa61>] kasan_slab_free+0x71/0xb0
[    3.293916]  [<ffffffff9459bac2>] kfree+0xa2/0x1f0
[    3.294168]  [<ffffffff9508158a>] scsi_device_dev_release_usercontext+0x50a/0x730
[    3.294598]  [<ffffffff941ace9a>] execute_in_process_context+0xda/0x130
[    3.294974]  [<ffffffff9508107c>] scsi_device_dev_release+0x1c/0x20
[    3.295322]  [<ffffffff94f566f6>] device_release+0x76/0x1e0
[    3.295626]  [<ffffffff94bc2db7>] kobject_release+0x107/0x370
[    3.295942]  [<ffffffff94bc29ce>] kobject_put+0x4e/0xa0
[    3.296222]  [<ffffffff94f56e17>] put_device+0x17/0x20
[    3.296497]  [<ffffffff9505201c>] scsi_device_put+0x7c/0xa0
[    3.296801]  [<ffffffff9507e1bc>] __scsi_scan_target+0xd4c/0xdf0
[    3.297132]  [<ffffffff9507e505>] scsi_scan_channel+0x105/0x160
[    3.297458]  [<ffffffff9507e8a2>] scsi_scan_host_selected+0x212/0x2f0
[    3.297829]  [<ffffffff9507eb3c>] do_scsi_scan_host+0x1bc/0x250
[    3.298156]  [<ffffffff9507efc1>] do_scan_async+0x41/0x450
[    3.298453]  [<ffffffff941c1fee>] async_run_entry_fn+0xfe/0x610
[    3.298777]  [<ffffffff941a9a84>] process_one_work+0x544/0x12d0
[    3.299105]  [<ffffffff941aa8e9>] worker_thread+0xd9/0x12f0
[    3.299408]  [<ffffffff941bb365>] kthread+0x1c5/0x260
[    3.299676]  [<ffffffff956dde9f>] ret_from_fork+0x1f/0x40
[    3.299967] Memory state around the buggy address:
[    3.300209]  ffff880254d8c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[    3.300608]  ffff880254d8c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[    3.300986] >ffff880254d8c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[    3.301408]                    ^
[    3.301550]  ffff880254d8c380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[    3.301987]  ffff880254d8c400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[    3.302396]
==================================================================

Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi: move function declarations to scsi_priv.h 2016-08-31T04:28:32+00:00 Baoyou Xie baoyou.xie@linaro.org 2016-08-30T11:26:00+00:00 d67e8b385fac90c100fb65b9534616769cd3f9b8 We get 2 warnings about global functions without a declaration in the scsi driver when building with W=1: drivers/scsi/scsi_lib.c:467:6: warning: no previous prototype for 'scsi_requeue_run_queue' [-Wmissing-prototypes] drivers/scsi/scsi_lib.c:2609:6: warning: no previous prototype for 'scsi_evt_thread' [-Wmissing-prototypes] In fact, both functions are declared in drivers/scsi/scsi_scan.c but need to move them into scsi_priv.h. Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
We get 2 warnings about global functions without a declaration in the
scsi driver when building with W=1:

drivers/scsi/scsi_lib.c:467:6: warning: no previous prototype for 'scsi_requeue_run_queue' [-Wmissing-prototypes]
drivers/scsi/scsi_lib.c:2609:6: warning: no previous prototype for 'scsi_evt_thread' [-Wmissing-prototypes]

In fact, both functions are declared in drivers/scsi/scsi_scan.c but
need to move them into scsi_priv.h.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi: Add intermediate STARGET_REMOVE state to scsi_target_state 2016-04-15T20:51:53+00:00 Johannes Thumshirn jthumshirn@suse.de 2016-04-05T09:50:44+00:00 f05795d3d771f30a7bdc3a138bf714b06d42aa95 Add intermediate STARGET_REMOVE state to scsi_target_state to avoid running into the BUG_ON() in scsi_target_reap(). The STARGET_REMOVE state is only valid in the path from scsi_remove_target() to scsi_target_destroy() indicating this target is going to be removed. This re-fixes the problem introduced in commits bc3f02a795d3 ("[SCSI] scsi_remove_target: fix softlockup regression on hot remove") and 40998193560d ("scsi: restart list search after unlock in scsi_remove_target") in a more comprehensive way. [mkp: Included James' fix for scsi_target_destroy()] Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Fixes: 40998193560dab6c3ce8d25f4fa58a23e252ef38 Cc: stable@vger.kernel.org Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: James Bottomley <jejb@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
Add intermediate STARGET_REMOVE state to scsi_target_state to avoid
running into the BUG_ON() in scsi_target_reap(). The STARGET_REMOVE
state is only valid in the path from scsi_remove_target() to
scsi_target_destroy() indicating this target is going to be removed.

This re-fixes the problem introduced in commits bc3f02a795d3 ("[SCSI]
scsi_remove_target: fix softlockup regression on hot remove") and
40998193560d ("scsi: restart list search after unlock in
scsi_remove_target") in a more comprehensive way.

[mkp: Included James' fix for scsi_target_destroy()]

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Fixes: 40998193560dab6c3ce8d25f4fa58a23e252ef38
Cc: stable@vger.kernel.org
Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: James Bottomley <jejb@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi: disable automatic target scan 2016-04-11T20:57:09+00:00 Hannes Reinecke hare@suse.de 2016-03-17T07:39:45+00:00 1d64508810d8d15867251c75a68d7250278ce2bd On larger installations it is useful to disable automatic LUN scanning, and only add the required LUNs via udev rules. This can speed up bootup dramatically. This patch introduces a new scan module parameter value 'manual', which works like 'none', but can be overridden by setting the 'rescan' value from scsi_scan_target to 'SCSI_SCAN_MANUAL'. And it updates all relevant callers to set the 'rescan' value to 'SCSI_SCAN_MANUAL' if invoked via the 'scan' option in sysfs. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Tested-by: Laurence Oberman <loberman@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
On larger installations it is useful to disable automatic LUN scanning,
and only add the required LUNs via udev rules.  This can speed up bootup
dramatically.

This patch introduces a new scan module parameter value 'manual', which
works like 'none', but can be overridden by setting the 'rescan' value
from scsi_scan_target to 'SCSI_SCAN_MANUAL'.  And it updates all
relevant callers to set the 'rescan' value to 'SCSI_SCAN_MANUAL' if
invoked via the 'scan' option in sysfs.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>