linux-stable.git/drivers/target/iscsi, branch linux-4.13.y

iscsi-target: Fix iscsi_np reset hung task during parallel delete

2017-08-06T21:41:41+00:00

This patch fixes a bug associated with iscsit_reset_np_thread()
that can occur during parallel configfs rmdir of a single iscsi_np
used across multiple iscsi-target instances, that would result in
hung task(s) similar to below where configfs rmdir process context
was blocked indefinately waiting for iscsi_np->np_restart_comp
to finish:

[ 6726.112076] INFO: task dcp_proxy_node_:15550 blocked for more than 120 seconds.
[ 6726.119440]       Tainted: G        W  O     4.1.26-3321 #2
[ 6726.125045] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 6726.132927] dcp_proxy_node_ D ffff8803f202bc88     0 15550      1 0x00000000
[ 6726.140058]  ffff8803f202bc88 ffff88085c64d960 ffff88083b3b1ad0 ffff88087fffeb08
[ 6726.147593]  ffff8803f202c000 7fffffffffffffff ffff88083f459c28 ffff88083b3b1ad0
[ 6726.155132]  ffff88035373c100 ffff8803f202bca8 ffffffff8168ced2 ffff8803f202bcb8
[ 6726.162667] Call Trace:
[ 6726.165150]  [] schedule+0x32/0x80
[ 6726.170156]  [] schedule_timeout+0x214/0x290
[ 6726.176030]  [] ? __send_signal+0x52/0x4a0
[ 6726.181728]  [] wait_for_completion+0x96/0x100
[ 6726.187774]  [] ? wake_up_state+0x10/0x10
[ 6726.193395]  [] iscsit_reset_np_thread+0x62/0xe0 [iscsi_target_mod]
[ 6726.201278]  [] iscsit_tpg_disable_portal_group+0x96/0x190 [iscsi_target_mod]
[ 6726.210033]  [] lio_target_tpg_store_enable+0x4f/0xc0 [iscsi_target_mod]
[ 6726.218351]  [] configfs_write_file+0xaa/0x110
[ 6726.224392]  [] vfs_write+0xa4/0x1b0
[ 6726.229576]  [] SyS_write+0x41/0xb0
[ 6726.234659]  [] system_call_fastpath+0x12/0x71

It would happen because each iscsit_reset_np_thread() sets state
to ISCSI_NP_THREAD_RESET, sends SIGINT, and then blocks waiting
for completion on iscsi_np->np_restart_comp.

However, if iscsi_np was active processing a login request and
more than a single iscsit_reset_np_thread() caller to the same
iscsi_np was blocked on iscsi_np->np_restart_comp, iscsi_np
kthread process context in __iscsi_target_login_thread() would
flush pending signals and only perform a single completion of
np->np_restart_comp before going back to sleep within transport
specific iscsit_transport->iscsi_accept_np code.

To address this bug, add a iscsi_np->np_reset_count and update
__iscsi_target_login_thread() to keep completing np->np_restart_comp
until ->np_reset_count has reached zero.

Reported-by: Gary Guo 
Tested-by: Gary Guo 
Cc: Mike Christie 
Cc: Hannes Reinecke 
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger

cxgbit: fix sg_nents calculation

2017-07-30T22:35:34+00:00

The current logic of calculating sg_nents can fail
if data_offset % PAGE_SIZE is not zero.

For example -
PAGE_SIZE = 4096
data_len = 3072
data_offset = 3072

As per current logic
sg_nents = max(1UL, DIV_ROUND_UP(data_len, PAGE_SIZE));
sg_nents = max(1UL, DIV_ROUND_UP(3072, 4096));
sg_nents = 1

But as data_offset % PAGE_SIZE = 3072 we should skip 3072 bytes
skip = 3K
sg_nents = max(1UL, DIV_ROUND_UP(3K(skip) + 3K(data_len), 4K(PAGE_SIZE));
sg_nents = 2;

This patch fixes this issue by adding skip to data_len.

Signed-off-by: Varun Prakash 
Signed-off-by: Nicholas Bellinger

iscsi-target: fix invalid flags in text response

2017-07-30T22:32:48+00:00

In case of multiple text responses iscsi-target
sets both 'F' and 'C' bit for the final text response
pdu, this issue happens because hdr->flags is not
zeroed out before ORing with 'F' bit.

This patch removes the | operator to fix this issue.

Signed-off-by: Varun Prakash 
Signed-off-by: Nicholas Bellinger

iscsi-target: fix memory leak in iscsit_setup_text_cmd()

2017-07-30T22:31:34+00:00

On receiving text request iscsi-target allocates buffer for
payload in iscsit_handle_text_cmd() and assigns buffer pointer
to cmd->text_in_ptr, this buffer is currently freed in
iscsit_release_cmd(), if iscsi-target sets 'C' bit in text
response then it will receive another text request from the
initiator with ttt != 0xffffffff in this case iscsi-target
will find cmd using itt and call iscsit_setup_text_cmd()
which will set cmd->text_in_ptr to NULL without freeing
previously allocated buffer.

This patch fixes this issue by calling kfree(cmd->text_in_ptr)
in iscsit_setup_text_cmd() before assigning NULL to it.

For the first text request cmd->text_in_ptr is NULL as
cmd is memset to 0 in iscsit_allocate_cmd().

Signed-off-by: Varun Prakash 
Cc:  # 4.0+
Signed-off-by: Nicholas Bellinger

cxgbit: add missing __kfree_skb()

2017-07-30T22:26:00+00:00

Call __kfree_skb() after processing skb to avoid
memory leak.

Signed-off-by: Varun Prakash 
Signed-off-by: Nicholas Bellinger

Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

2017-07-15T19:44:02+00:00

Pull random updates from Ted Ts'o:
 "Add wait_for_random_bytes() and get_random_*_wait() functions so that
  callers can more safely get random bytes if they can block until the
  CRNG is initialized.

  Also print a warning if get_random_*() is called before the CRNG is
  initialized. By default, only one single-line warning will be printed
  per boot. If CONFIG_WARN_ALL_UNSEEDED_RANDOM is defined, then a
  warning will be printed for each function which tries to get random
  bytes before the CRNG is initialized. This can get spammy for certain
  architecture types, so it is not enabled by default"

* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: reorder READ_ONCE() in get_random_uXX
  random: suppress spammy warnings about unseeded randomness
  random: warn when kernel uses unseeded randomness
  net/route: use get_random_int for random counter
  net/neighbor: use get_random_u32 for 32-bit hash random
  rhashtable: use get_random_u32 for hash_rnd
  ceph: ensure RNG is seeded before using
  iscsi: ensure RNG is seeded before use
  cifs: use get_random_u32 for 32-bit lock random
  random: add get_random_{bytes,u32,u64,int,long,once}_wait family
  random: add wait_for_random_bytes() API

Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

2017-07-13T21:27:32+00:00

Pull SCSI target updates from Nicholas Bellinger:
 "It's been usually busy for summer, with most of the efforts centered
  around TCMU developments and various target-core + fabric driver bug
  fixing activities. Not particularly large in terms of LoC, but lots of
  smaller patches from many different folks.

  The highlights include:

   - ibmvscsis logical partition manager support (Michael Cyr + Bryant
     Ly)

   - Convert target/iblock WRITE_SAME to blkdev_issue_zeroout (hch +
     nab)

   - Add support for TMR percpu LUN reference counting (nab)

   - Fix a potential deadlock between EXTENDED_COPY and iscsi shutdown
     (Bart)

   - Fix COMPARE_AND_WRITE caw_sem leak during se_cmd quiesce (Jiang Yi)

   - Fix TMCU module removal (Xiubo Li)

   - Fix iser-target OOPs during login failure (Andrea Righi + Sagi)

   - Breakup target-core free_device backend driver callback (mnc)

   - Perform TCMU add/delete/reconfig synchronously (mnc)

   - Fix TCMU multiple UIO open/close sequences (mnc)

   - Fix TCMU CHECK_CONDITION sense handling (mnc)

   - Fix target-core SAM_STAT_BUSY + TASK_SET_FULL handling (mnc + nab)

   - Introduce TYPE_ZBC support in PSCSI (Damien Le Moal)

   - Fix possible TCMU memory leak + OOPs when recalculating cmd base
     size (Xiubo Li + Bryant Ly + Damien Le Moal + mnc)

   - Add login_keys_workaround attribute for non RFC initiators (Robert
     LeBlanc + Arun Easi + nab)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (68 commits)
  iscsi-target: Add login_keys_workaround attribute for non RFC initiators
  Revert "qla2xxx: Fix incorrect tcm_qla2xxx_free_cmd use during TMR ABORT"
  tcmu: clean up the code and with one small fix
  tcmu: Fix possbile memory leak / OOPs when recalculating cmd base size
  target: export lio pgr/alua support as device attr
  target: Fix return sense reason in target_scsi3_emulate_pr_out
  target: Fix cmd size for PR-OUT in passthrough_parse_cdb
  tcmu: Fix dev_config_store
  target: pscsi: Introduce TYPE_ZBC support
  target: Use macro for WRITE_VERIFY_32 operation codes
  target: fix SAM_STAT_BUSY/TASK_SET_FULL handling
  target: remove transport_complete
  pscsi: finish cmd processing from pscsi_req_done
  tcmu: fix sense handling during completion
  target: add helper to copy sense to se_cmd buffer
  target: do not require a transport_complete for SCF_TRANSPORT_TASK_SENSE
  target: make device_mutex and device_list static
  tcmu: Fix flushing cmd entry dcache page
  tcmu: fix multiple uio open/close sequences
  tcmu: drop configured check in destroy
  ...

iscsi-target: Add login_keys_workaround attribute for non RFC initiators

2017-07-11T17:56:39+00:00

This patch re-introduces part of a long standing login workaround that
was recently dropped by:

  commit 1c99de981f30b3e7868b8d20ce5479fa1c0fea46
  Author: Nicholas Bellinger 
  Date:   Sun Apr 2 13:36:44 2017 -0700

      iscsi-target: Drop work-around for legacy GlobalSAN initiator

Namely, the workaround for FirstBurstLength ended up being required by
Mellanox Flexboot PXE boot ROMs as reported by Robert.

So this patch re-adds the work-around for FirstBurstLength within
iscsi_check_proposer_for_optional_reply(), and makes the key optional
to respond when the initiator does not propose, nor respond to it.

Also as requested by Arun, this patch introduces a new TPG attribute
named 'login_keys_workaround' that controls the use of both the
FirstBurstLength workaround, as well as the two other existing
workarounds for gPXE iSCSI boot client.

By default, the workaround is enabled with login_keys_workaround=1,
since Mellanox FlexBoot requires it, and Arun has verified the Qlogic
MSFT initiator already proposes FirstBurstLength, so it's uneffected
by this re-adding this part of the original work-around.

Reported-by: Robert LeBlanc 
Cc: Robert LeBlanc 
Reviewed-by: Arun Easi 
Cc:  # 3.1+
Signed-off-by: Nicholas Bellinger

target/iscsi: Remove dead code from iscsit_process_scsi_cmd()

2017-07-07T06:11:28+00:00

If an iSCSI command is rejected before iscsit_process_scsi_cmd()
is called, .reject_reason is set but iscsit_process_scsi_cmd() is
not called. This means that the "if (cmd->reject_reason) ..." code
in this function can be removed without changing the behavior of
this function.

Signed-off-by: Bart Van Assche 
Cc: Hannes Reinecke 
Cc: Christoph Hellwig 
Cc: Andy Grover 
Cc: David Disseldorp 
Signed-off-by: Nicholas Bellinger

target/iscsi: Simplify iscsit_free_cmd()

2017-07-07T06:11:27+00:00

Since .se_tfo is only set if a command has been submitted to
the LIO core, check .se_tfo instead of .iscsi_opcode. Since
__iscsit_free_cmd() only affects SCSI commands but not TMFs,
calling that function for TMFs does not change behavior. This
patch does not change the behavior of iscsit_free_cmd().

Signed-off-by: Bart Van Assche 
Cc: Hannes Reinecke 
Cc: Christoph Hellwig 
Cc: Andy Grover 
Cc: David Disseldorp 
Signed-off-by: Nicholas Bellinger