linux-stable.git/drivers/target/iscsi, branch linux-5.5.y Linux kernel stable tree scsi: target: fix hang when multiple threads try to destroy the same iscsi session 2020-04-21T07:06:45+00:00 Maurizio Lombardi mlombard@redhat.com 2020-03-13T17:06:55+00:00 c677beddf3aee21ee9987abd2c7d9e61953c6051 [ Upstream commit 57c46e9f33da530a2485fa01aa27b6d18c28c796 ] A number of hangs have been reported against the target driver; they are due to the fact that multiple threads may try to destroy the iscsi session at the same time. This may be reproduced for example when a "targetcli iscsi/iqn.../tpg1 disable" command is executed while a logout operation is underway. When this happens, two or more threads may end up sleeping and waiting for iscsit_close_connection() to execute "complete(session_wait_comp)". Only one of the threads will wake up and proceed to destroy the session structure, the remaining threads will hang forever. Note that if the blocked threads are somehow forced to wake up with complete_all(), they will try to free the same iscsi session structure destroyed by the first thread, causing double frees, memory corruptions etc... With this patch, the threads that want to destroy the iscsi session will increase the session refcount and will set the "session_close" flag to 1; then they wait for the driver to close the remaining active connections. When the last connection is closed, iscsit_close_connection() will wake up all the threads and will wait for the session's refcount to reach zero; when this happens, iscsit_close_connection() will destroy the session structure because no one is referencing it anymore. INFO: task targetcli:5971 blocked for more than 120 seconds. Tainted: P OE 4.15.0-72-generic #81~16.04.1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. targetcli D 0 5971 1 0x00000080 Call Trace: __schedule+0x3d6/0x8b0 ? vprintk_func+0x44/0xe0 schedule+0x36/0x80 schedule_timeout+0x1db/0x370 ? __dynamic_pr_debug+0x8a/0xb0 wait_for_completion+0xb4/0x140 ? wake_up_q+0x70/0x70 iscsit_free_session+0x13d/0x1a0 [iscsi_target_mod] iscsit_release_sessions_for_tpg+0x16b/0x1e0 [iscsi_target_mod] iscsit_tpg_disable_portal_group+0xca/0x1c0 [iscsi_target_mod] lio_target_tpg_enable_store+0x66/0xe0 [iscsi_target_mod] configfs_write_file+0xb9/0x120 __vfs_write+0x1b/0x40 vfs_write+0xb8/0x1b0 SyS_write+0x5c/0xe0 do_syscall_64+0x73/0x130 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Link: https://lore.kernel.org/r/20200313170656.9716-3-mlombard@redhat.com Reported-by: Matt Coleman <mcoleman@datto.com> Tested-by: Matt Coleman <mcoleman@datto.com> Tested-by: Rahul Kundu <rahul.kundu@chelsio.com> Signed-off-by: Maurizio Lombardi <mlombard@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 57c46e9f33da530a2485fa01aa27b6d18c28c796 ]

A number of hangs have been reported against the target driver; they are
due to the fact that multiple threads may try to destroy the iscsi session
at the same time. This may be reproduced for example when a "targetcli
iscsi/iqn.../tpg1 disable" command is executed while a logout operation is
underway.

When this happens, two or more threads may end up sleeping and waiting for
iscsit_close_connection() to execute "complete(session_wait_comp)".  Only
one of the threads will wake up and proceed to destroy the session
structure, the remaining threads will hang forever.

Note that if the blocked threads are somehow forced to wake up with
complete_all(), they will try to free the same iscsi session structure
destroyed by the first thread, causing double frees, memory corruptions
etc...

With this patch, the threads that want to destroy the iscsi session will
increase the session refcount and will set the "session_close" flag to 1;
then they wait for the driver to close the remaining active connections.
When the last connection is closed, iscsit_close_connection() will wake up
all the threads and will wait for the session's refcount to reach zero;
when this happens, iscsit_close_connection() will destroy the session
structure because no one is referencing it anymore.

 INFO: task targetcli:5971 blocked for more than 120 seconds.
       Tainted: P           OE    4.15.0-72-generic #81~16.04.1
 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
 targetcli       D    0  5971      1 0x00000080
 Call Trace:
  __schedule+0x3d6/0x8b0
  ? vprintk_func+0x44/0xe0
  schedule+0x36/0x80
  schedule_timeout+0x1db/0x370
  ? __dynamic_pr_debug+0x8a/0xb0
  wait_for_completion+0xb4/0x140
  ? wake_up_q+0x70/0x70
  iscsit_free_session+0x13d/0x1a0 [iscsi_target_mod]
  iscsit_release_sessions_for_tpg+0x16b/0x1e0 [iscsi_target_mod]
  iscsit_tpg_disable_portal_group+0xca/0x1c0 [iscsi_target_mod]
  lio_target_tpg_enable_store+0x66/0xe0 [iscsi_target_mod]
  configfs_write_file+0xb9/0x120
  __vfs_write+0x1b/0x40
  vfs_write+0xb8/0x1b0
  SyS_write+0x5c/0xe0
  do_syscall_64+0x73/0x130
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Link: https://lore.kernel.org/r/20200313170656.9716-3-mlombard@redhat.com
Reported-by: Matt Coleman <mcoleman@datto.com>
Tested-by: Matt Coleman <mcoleman@datto.com>
Tested-by: Rahul Kundu <rahul.kundu@chelsio.com>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
scsi: target: remove boilerplate code 2020-04-21T07:06:45+00:00 Maurizio Lombardi mlombard@redhat.com 2020-03-13T17:06:54+00:00 d28d64c667873abbced1fec96b7854897aa06488 [ Upstream commit e49a7d994379278d3353d7ffc7994672752fb0ad ] iscsit_free_session() is equivalent to iscsit_stop_session() followed by a call to iscsit_close_session(). Link: https://lore.kernel.org/r/20200313170656.9716-2-mlombard@redhat.com Tested-by: Rahul Kundu <rahul.kundu@chelsio.com> Signed-off-by: Maurizio Lombardi <mlombard@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e49a7d994379278d3353d7ffc7994672752fb0ad ]

iscsit_free_session() is equivalent to iscsit_stop_session() followed by a
call to iscsit_close_session().

Link: https://lore.kernel.org/r/20200313170656.9716-2-mlombard@redhat.com
Tested-by: Rahul Kundu <rahul.kundu@chelsio.com>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
scsi: Revert "target: iscsi: Wait for all commands to finish before freeing a session" 2020-02-28T16:23:42+00:00 Bart Van Assche bvanassche@acm.org 2020-02-13T05:09:00+00:00 4fc010340bc162cf147712fd4d7ee83d4d764692 commit 807b9515b7d044cf77df31f1af9d842a76ecd5cb upstream. Since commit e9d3009cb936 introduced a regression and since the fix for that regression was not perfect, revert this commit. Link: https://marc.info/?l=target-devel&m=158157054906195 Cc: Rahul Kundu <rahul.kundu@chelsio.com> Cc: Mike Marciniszyn <mike.marciniszyn@intel.com> Cc: Sagi Grimberg <sagi@grimberg.me> Reported-by: Dakshaja Uppalapati <dakshaja@chelsio.com> Fixes: e9d3009cb936 ("scsi: target: iscsi: Wait for all commands to finish before freeing a session") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 807b9515b7d044cf77df31f1af9d842a76ecd5cb upstream.

Since commit e9d3009cb936 introduced a regression and since the fix for
that regression was not perfect, revert this commit.

Link: https://marc.info/?l=target-devel&m=158157054906195
Cc: Rahul Kundu <rahul.kundu@chelsio.com>
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Reported-by: Dakshaja Uppalapati <dakshaja@chelsio.com>
Fixes: e9d3009cb936 ("scsi: target: iscsi: Wait for all commands to finish before freeing a session")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
scsi: Revert "RDMA/isert: Fix a recently introduced regression related to logout" 2020-02-28T16:23:42+00:00 Bart Van Assche bvanassche@acm.org 2020-02-13T05:08:59+00:00 e473567240c086efa4427c644f3a8fbe78cef144 commit 76261ada16dcc3be610396a46d35acc3efbda682 upstream. Since commit 04060db41178 introduces soft lockups when toggling network interfaces, revert it. Link: https://marc.info/?l=target-devel&m=158157054906196 Cc: Rahul Kundu <rahul.kundu@chelsio.com> Cc: Mike Marciniszyn <mike.marciniszyn@intel.com> Cc: Sagi Grimberg <sagi@grimberg.me> Reported-by: Dakshaja Uppalapati <dakshaja@chelsio.com> Fixes: 04060db41178 ("scsi: RDMA/isert: Fix a recently introduced regression related to logout") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 76261ada16dcc3be610396a46d35acc3efbda682 upstream.

Since commit 04060db41178 introduces soft lockups when toggling network
interfaces, revert it.

Link: https://marc.info/?l=target-devel&m=158157054906196
Cc: Rahul Kundu <rahul.kundu@chelsio.com>
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Reported-by: Dakshaja Uppalapati <dakshaja@chelsio.com>
Fixes: 04060db41178 ("scsi: RDMA/isert: Fix a recently introduced regression related to logout")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi 2020-01-26T18:39:09+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-01-26T18:39:09+00:00 54343d951838ef4e423de7d124616bf66eca92e7 Pull SCSI fixes from James Bottomley: "Two last minute fixes, both in drivers. The fnic one is a highly unlikely condition, but the RDMA one is a recently introduced regression that causes a kernel warning to trigger in every RDMA logon, which would be unsightly if it got into the final release" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: scsi: RDMA/isert: Fix a recently introduced regression related to logout scsi: fnic: do not queue commands during fwreset 
Pull SCSI fixes from James Bottomley:
 "Two last minute fixes, both in drivers.

  The fnic one is a highly unlikely condition, but the RDMA one is a
  recently introduced regression that causes a kernel warning to trigger
  in every RDMA logon, which would be unsightly if it got into the final
  release"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: RDMA/isert: Fix a recently introduced regression related to logout
  scsi: fnic: do not queue commands during fwreset
scsi: RDMA/isert: Fix a recently introduced regression related to logout 2020-01-21T05:24:46+00:00 Bart Van Assche bvanassche@acm.org 2020-01-16T04:47:37+00:00 04060db41178c7c244f2c7dcd913e7fd331de915 iscsit_close_connection() calls isert_wait_conn(). Due to commit e9d3009cb936 both functions call target_wait_for_sess_cmds() although that last function should be called only once. Fix this by removing the target_wait_for_sess_cmds() call from isert_wait_conn() and by only calling isert_wait_conn() after target_wait_for_sess_cmds(). Fixes: e9d3009cb936 ("scsi: target: iscsi: Wait for all commands to finish before freeing a session"). Link: https://lore.kernel.org/r/20200116044737.19507-1-bvanassche@acm.org Reported-by: Rahul Kundu <rahul.kundu@chelsio.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Acked-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
iscsit_close_connection() calls isert_wait_conn(). Due to commit
e9d3009cb936 both functions call target_wait_for_sess_cmds() although that
last function should be called only once. Fix this by removing the
target_wait_for_sess_cmds() call from isert_wait_conn() and by only calling
isert_wait_conn() after target_wait_for_sess_cmds().

Fixes: e9d3009cb936 ("scsi: target: iscsi: Wait for all commands to finish before freeing a session").
Link: https://lore.kernel.org/r/20200116044737.19507-1-bvanassche@acm.org
Reported-by: Rahul Kundu <rahul.kundu@chelsio.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
treewide: Use sizeof_field() macro 2019-12-09T18:36:44+00:00 Pankaj Bharadiya pankaj.laxminarayan.bharadiya@intel.com 2019-12-09T18:31:43+00:00 c593642c8be046915ca3a4a300243a68077cd207 Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except at places where these are defined. Later patches will remove the unused definition of FIELD_SIZEOF(). This patch is generated using following script: EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h" git grep -l -e "\bFIELD_SIZEOF\b" | while read file; do if [[ "$file" =~ $EXCLUDE_FILES ]]; then continue fi sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file; done Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com> Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: David Miller <davem@davemloft.net> # for net 
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().

This patch is generated using following script:

EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"

git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do

	if [[ "$file" =~ $EXCLUDE_FILES ]]; then
		continue
	fi
	sed -i  -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done

Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi 2019-12-02T21:37:02+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-12-02T21:37:02+00:00 ef2cc88e2a205b8a11a19e78db63a70d3728cdf5 Pull SCSI updates from James Bottomley: "This is mostly update of the usual drivers: aacraid, ufs, zfcp, NCR5380, lpfc, qla2xxx, smartpqi, hisi_sas, target, mpt3sas, pm80xx plus a whole load of minor updates and fixes. The major core changes are Al Viro's reworking of sg's handling of copy to/from user, Ming Lei's removal of the host busy counter to avoid contention in the multiqueue case and Damien Le Moal's fixing of residual tracking across error handling" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (251 commits) scsi: bnx2fc: timeout calculation invalid for bnx2fc_eh_abort() scsi: target: core: Fix a pr_debug() argument scsi: iscsi: Don't send data to unbound connection scsi: target: iscsi: Wait for all commands to finish before freeing a session scsi: target: core: Release SPC-2 reservations when closing a session scsi: target: core: Document target_cmd_size_check() scsi: bnx2i: fix potential use after free Revert "scsi: qla2xxx: Fix memory leak when sending I/O fails" scsi: NCR5380: Add disconnect_mask module parameter scsi: NCR5380: Unconditionally clear ICR after do_abort() scsi: NCR5380: Call scsi_set_resid() on command completion scsi: scsi_debug: num_tgts must be >= 0 scsi: lpfc: use hdwq assigned cpu for allocation scsi: arcmsr: fix indentation issues scsi: qla4xxx: fix double free bug scsi: pm80xx: Modified the logic to collect fatal dump scsi: pm80xx: Tie the interrupt name to the module instance scsi: pm80xx: Controller fatal error through sysfs scsi: pm80xx: Do not request 12G sas speeds scsi: pm80xx: Cleanup command when a reset times out ... 
Pull SCSI updates from James Bottomley:
 "This is mostly update of the usual drivers: aacraid, ufs, zfcp,
  NCR5380, lpfc, qla2xxx, smartpqi, hisi_sas, target, mpt3sas, pm80xx
  plus a whole load of minor updates and fixes.

  The major core changes are Al Viro's reworking of sg's handling of
  copy to/from user, Ming Lei's removal of the host busy counter to
  avoid contention in the multiqueue case and Damien Le Moal's fixing of
  residual tracking across error handling"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (251 commits)
  scsi: bnx2fc: timeout calculation invalid for bnx2fc_eh_abort()
  scsi: target: core: Fix a pr_debug() argument
  scsi: iscsi: Don't send data to unbound connection
  scsi: target: iscsi: Wait for all commands to finish before freeing a session
  scsi: target: core: Release SPC-2 reservations when closing a session
  scsi: target: core: Document target_cmd_size_check()
  scsi: bnx2i: fix potential use after free
  Revert "scsi: qla2xxx: Fix memory leak when sending I/O fails"
  scsi: NCR5380: Add disconnect_mask module parameter
  scsi: NCR5380: Unconditionally clear ICR after do_abort()
  scsi: NCR5380: Call scsi_set_resid() on command completion
  scsi: scsi_debug: num_tgts must be >= 0
  scsi: lpfc: use hdwq assigned cpu for allocation
  scsi: arcmsr: fix indentation issues
  scsi: qla4xxx: fix double free bug
  scsi: pm80xx: Modified the logic to collect fatal dump
  scsi: pm80xx: Tie the interrupt name to the module instance
  scsi: pm80xx: Controller fatal error through sysfs
  scsi: pm80xx: Do not request 12G sas speeds
  scsi: pm80xx: Cleanup command when a reset times out
  ...
scsi: target: iscsi: Wait for all commands to finish before freeing a session 2019-11-20T02:37:35+00:00 Bart Van Assche bvanassche@acm.org 2019-11-13T22:05:08+00:00 e9d3009cb936bd0faf0719f68d98ad8afb1e613b The iSCSI target driver is the only target driver that does not wait for ongoing commands to finish before freeing a session. Make the iSCSI target driver wait for ongoing commands to finish before freeing a session. This patch fixes the following KASAN complaint: BUG: KASAN: use-after-free in __lock_acquire+0xb1a/0x2710 Read of size 8 at addr ffff8881154eca70 by task kworker/0:2/247 CPU: 0 PID: 247 Comm: kworker/0:2 Not tainted 5.4.0-rc1-dbg+ #6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Workqueue: target_completion target_complete_ok_work [target_core_mod] Call Trace: dump_stack+0x8a/0xd6 print_address_description.constprop.0+0x40/0x60 __kasan_report.cold+0x1b/0x33 kasan_report+0x16/0x20 __asan_load8+0x58/0x90 __lock_acquire+0xb1a/0x2710 lock_acquire+0xd3/0x200 _raw_spin_lock_irqsave+0x43/0x60 target_release_cmd_kref+0x162/0x7f0 [target_core_mod] target_put_sess_cmd+0x2e/0x40 [target_core_mod] lio_check_stop_free+0x12/0x20 [iscsi_target_mod] transport_cmd_check_stop_to_fabric+0xd8/0xe0 [target_core_mod] target_complete_ok_work+0x1b0/0x790 [target_core_mod] process_one_work+0x549/0xa40 worker_thread+0x7a/0x5d0 kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 Allocated by task 889: save_stack+0x23/0x90 __kasan_kmalloc.constprop.0+0xcf/0xe0 kasan_slab_alloc+0x12/0x20 kmem_cache_alloc+0xf6/0x360 transport_alloc_session+0x29/0x80 [target_core_mod] iscsi_target_login_thread+0xcd6/0x18f0 [iscsi_target_mod] kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 Freed by task 1025: save_stack+0x23/0x90 __kasan_slab_free+0x13a/0x190 kasan_slab_free+0x12/0x20 kmem_cache_free+0x146/0x400 transport_free_session+0x179/0x2f0 [target_core_mod] transport_deregister_session+0x130/0x180 [target_core_mod] iscsit_close_session+0x12c/0x350 [iscsi_target_mod] iscsit_logout_post_handler+0x136/0x380 [iscsi_target_mod] iscsit_response_queue+0x8de/0xbe0 [iscsi_target_mod] iscsi_target_tx_thread+0x27f/0x370 [iscsi_target_mod] kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 The buggy address belongs to the object at ffff8881154ec9c0 which belongs to the cache se_sess_cache of size 352 The buggy address is located 176 bytes inside of 352-byte region [ffff8881154ec9c0, ffff8881154ecb20) The buggy address belongs to the page: page:ffffea0004553b00 refcount:1 mapcount:0 mapping:ffff888101755400 index:0x0 compound_mapcount: 0 flags: 0x2fff000000010200(slab|head) raw: 2fff000000010200 dead000000000100 dead000000000122 ffff888101755400 raw: 0000000000000000 0000000080130013 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881154ec900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881154ec980: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff8881154eca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881154eca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881154ecb00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc Cc: Mike Christie <mchristi@redhat.com> Link: https://lore.kernel.org/r/20191113220508.198257-3-bvanassche@acm.org Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
The iSCSI target driver is the only target driver that does not wait for
ongoing commands to finish before freeing a session. Make the iSCSI target
driver wait for ongoing commands to finish before freeing a session. This
patch fixes the following KASAN complaint:

BUG: KASAN: use-after-free in __lock_acquire+0xb1a/0x2710
Read of size 8 at addr ffff8881154eca70 by task kworker/0:2/247

CPU: 0 PID: 247 Comm: kworker/0:2 Not tainted 5.4.0-rc1-dbg+ #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Workqueue: target_completion target_complete_ok_work [target_core_mod]
Call Trace:
 dump_stack+0x8a/0xd6
 print_address_description.constprop.0+0x40/0x60
 __kasan_report.cold+0x1b/0x33
 kasan_report+0x16/0x20
 __asan_load8+0x58/0x90
 __lock_acquire+0xb1a/0x2710
 lock_acquire+0xd3/0x200
 _raw_spin_lock_irqsave+0x43/0x60
 target_release_cmd_kref+0x162/0x7f0 [target_core_mod]
 target_put_sess_cmd+0x2e/0x40 [target_core_mod]
 lio_check_stop_free+0x12/0x20 [iscsi_target_mod]
 transport_cmd_check_stop_to_fabric+0xd8/0xe0 [target_core_mod]
 target_complete_ok_work+0x1b0/0x790 [target_core_mod]
 process_one_work+0x549/0xa40
 worker_thread+0x7a/0x5d0
 kthread+0x1bc/0x210
 ret_from_fork+0x24/0x30

Allocated by task 889:
 save_stack+0x23/0x90
 __kasan_kmalloc.constprop.0+0xcf/0xe0
 kasan_slab_alloc+0x12/0x20
 kmem_cache_alloc+0xf6/0x360
 transport_alloc_session+0x29/0x80 [target_core_mod]
 iscsi_target_login_thread+0xcd6/0x18f0 [iscsi_target_mod]
 kthread+0x1bc/0x210
 ret_from_fork+0x24/0x30

Freed by task 1025:
 save_stack+0x23/0x90
 __kasan_slab_free+0x13a/0x190
 kasan_slab_free+0x12/0x20
 kmem_cache_free+0x146/0x400
 transport_free_session+0x179/0x2f0 [target_core_mod]
 transport_deregister_session+0x130/0x180 [target_core_mod]
 iscsit_close_session+0x12c/0x350 [iscsi_target_mod]
 iscsit_logout_post_handler+0x136/0x380 [iscsi_target_mod]
 iscsit_response_queue+0x8de/0xbe0 [iscsi_target_mod]
 iscsi_target_tx_thread+0x27f/0x370 [iscsi_target_mod]
 kthread+0x1bc/0x210
 ret_from_fork+0x24/0x30

The buggy address belongs to the object at ffff8881154ec9c0
 which belongs to the cache se_sess_cache of size 352
The buggy address is located 176 bytes inside of
 352-byte region [ffff8881154ec9c0, ffff8881154ecb20)
The buggy address belongs to the page:
page:ffffea0004553b00 refcount:1 mapcount:0 mapping:ffff888101755400 index:0x0 compound_mapcount: 0
flags: 0x2fff000000010200(slab|head)
raw: 2fff000000010200 dead000000000100 dead000000000122 ffff888101755400
raw: 0000000000000000 0000000080130013 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881154ec900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881154ec980: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
>ffff8881154eca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff8881154eca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881154ecb00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc

Cc: Mike Christie <mchristi@redhat.com>
Link: https://lore.kernel.org/r/20191113220508.198257-3-bvanassche@acm.org
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi: target: iscsi: rename some variables to avoid confusion. 2019-11-06T05:14:33+00:00 Maurizio Lombardi mlombard@redhat.com 2019-10-17T13:10:37+00:00 f9fab3d9860050ed69b7cee348a449a7853a3259 This patch renames some variables in chap_server_compute_hash() to make it harder to confuse the initiator's challenge with the target's challenge when the mutual chap authentication is used. Link: https://lore.kernel.org/r/20191017131037.9903-4-mlombard@redhat.com Signed-off-by: Maurizio Lombardi <mlombard@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> 
This patch renames some variables in chap_server_compute_hash() to make it
harder to confuse the initiator's challenge with the target's challenge
when the mutual chap authentication is used.

Link: https://lore.kernel.org/r/20191017131037.9903-4-mlombard@redhat.com
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>