linux-stable.git/drivers/target, branch v4.9.243

scsi: target: iscsi: Fix hang in iscsit_access_np() when getting tpg->np_login_sem

2020-09-23T06:46:12+00:00

commit ed43ffea78dcc97db3f561da834f1a49c8961e33 upstream.

The iSCSI target login thread might get stuck with the following stack:

cat /proc/`pidof iscsi_np`/stack
[<0>] down_interruptible+0x42/0x50
[<0>] iscsit_access_np+0xe3/0x167
[<0>] iscsi_target_locate_portal+0x695/0x8ac
[<0>] __iscsi_target_login_thread+0x855/0xb82
[<0>] iscsi_target_login_thread+0x2f/0x5a
[<0>] kthread+0xfa/0x130
[<0>] ret_from_fork+0x1f/0x30

This can be reproduced via the following steps:

1. Initiator A tries to log in to iqn1-tpg1 on port 3260. After finishing
   PDU exchange in the login thread and before the negotiation is finished
   the the network link goes down. At this point A has not finished login
   and tpg->np_login_sem is held.

2. Initiator B tries to log in to iqn2-tpg1 on port 3260. After finishing
   PDU exchange in the login thread the target expects to process remaining
   login PDUs in workqueue context.

3. Initiator A' tries to log in to iqn1-tpg1 on port 3260 from a new
   socket. A' will wait for tpg->np_login_sem with np->np_login_timer
   loaded to wait for at most 15 seconds. The lock is held by A so A'
   eventually times out.

4. Before A' got timeout initiator B gets negotiation failed and calls
   iscsi_target_login_drop()->iscsi_target_login_sess_out().  The
   np->np_login_timer is canceled and initiator A' will hang forever.
   Because A' is now in the login thread, no new login requests can be
   serviced.

Fix this by moving iscsi_stop_login_thread_timer() out of
iscsi_target_login_sess_out(). Also remove iscsi_np parameter from
iscsi_target_login_sess_out().

Link: https://lore.kernel.org/r/20200729130343.24976-1-houpu@bytedance.com
Cc: stable@vger.kernel.org
Reviewed-by: Mike Christie 
Signed-off-by: Hou Pu 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: target: iscsi: Fix data digest calculation

2020-09-23T06:46:12+00:00

commit 5528d03183fe5243416c706f64b1faa518b05130 upstream.

Current code does not consider 'page_off' in data digest calculation. To
fix this, add a local variable 'first_sg' and set first_sg.offset to
sg->offset + page_off.

Link: https://lore.kernel.org/r/1598358910-3052-1-git-send-email-varun@chelsio.com
Fixes: e48354ce078c ("iscsi-target: Add iSCSI fabric support for target v4.1")
Cc: 
Reviewed-by: Mike Christie 
Signed-off-by: Varun Prakash 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: target: tcmu: Fix crash on ARM during cmd completion

2020-09-03T09:21:16+00:00

[ Upstream commit 5a0c256d96f020e4771f6fd5524b80f89a2d3132 ]

If tcmu_handle_completions() has to process a padding shorter than
sizeof(struct tcmu_cmd_entry), the current call to
tcmu_flush_dcache_range() with sizeof(struct tcmu_cmd_entry) as length
param is wrong and causes crashes on e.g. ARM, because
tcmu_flush_dcache_range() in this case calls
flush_dcache_page(vmalloc_to_page(start)); with start being an invalid
address above the end of the vmalloc'ed area.

The fix is to use the minimum of remaining ring space and sizeof(struct
tcmu_cmd_entry) as the length param.

The patch was tested on kernel 4.19.118.

See https://bugzilla.kernel.org/show_bug.cgi?id=208045#c10

Link: https://lore.kernel.org/r/20200629093756.8947-1-bstroesser@ts.fujitsu.com
Tested-by: JiangYu 
Acked-by: Mike Christie 
Signed-off-by: Bodo Stroesser 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: target: fix PR IN / READ FULL STATUS for FC

2020-05-02T15:23:17+00:00

[ Upstream commit 8fed04eb79a74cbf471dfaa755900a51b37273ab ]

Creation of the response to READ FULL STATUS fails for FC based
reservations. Reason is the too high loop limit (< 24) in
fc_get_pr_transport_id(). The string representation of FC WWPN is 23 chars
long only ("11:22:33:44:55:66:77:88"). So when i is 23, the loop body is
executed a last time for the ending '\0' of the string and thus hex2bin()
reports an error.

Link: https://lore.kernel.org/r/20200408132610.14623-3-bstroesser@ts.fujitsu.com
Signed-off-by: Bodo Stroesser 
Reviewed-by: Mike Christie 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: target: fix hang when multiple threads try to destroy the same iscsi session

2020-04-24T05:59:06+00:00

[ 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 
Tested-by: Matt Coleman 
Tested-by: Rahul Kundu 
Signed-off-by: Maurizio Lombardi 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: target: remove boilerplate code

2020-04-24T05:59:05+00:00

[ 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 
Signed-off-by: Maurizio Lombardi 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: Revert "target: iscsi: Wait for all commands to finish before freeing a session"

2020-02-28T14:42:54+00:00

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 
Cc: Mike Marciniszyn 
Cc: Sagi Grimberg 
Reported-by: Dakshaja Uppalapati 
Fixes: e9d3009cb936 ("scsi: target: iscsi: Wait for all commands to finish before freeing a session")
Signed-off-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: Revert "RDMA/isert: Fix a recently introduced regression related to logout"

2020-02-28T14:42:54+00:00

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 
Cc: Mike Marciniszyn 
Cc: Sagi Grimberg 
Reported-by: Dakshaja Uppalapati 
Fixes: 04060db41178 ("scsi: RDMA/isert: Fix a recently introduced regression related to logout")
Signed-off-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: RDMA/isert: Fix a recently introduced regression related to logout

2020-01-29T09:24:39+00:00

commit 04060db41178c7c244f2c7dcd913e7fd331de915 upstream.

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 
Signed-off-by: Bart Van Assche 
Tested-by: Mike Marciniszyn 
Acked-by: Sagi Grimberg 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: target: core: Fix a pr_debug() argument

2020-01-23T07:19:43+00:00

commit c941e0d172605731de9b4628bd4146d35cf2e7d6 upstream.

Print the string for which conversion failed instead of printing the
function name twice.

Fixes: 2650d71e244f ("target: move transport ID handling to the core")
Cc: Christoph Hellwig 
Link: https://lore.kernel.org/r/20191107215525.64415-1-bvanassche@acm.org
Signed-off-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman