Subject: CVE-2024-26873: scsi: hisi_sas: Fix a deadlock issue related to automatic dump

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

scsi: hisi_sas: Fix a deadlock issue related to automatic dump

If we issue a disabling PHY command, the device attached with it will go
offline, if a 2 bit ECC error occurs at the same time, a hung task may be
found:

[ 4613.652388] INFO: task kworker/u256:0:165233 blocked for more than 120 seconds.
[ 4613.666297] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 4613.674809] task:kworker/u256:0  state:D stack:    0 pid:165233 ppid:     2 flags:0x00000208
[ 4613.683959] Workqueue: 0000:74:02.0_disco_q sas_revalidate_domain [libsas]
[ 4613.691518] Call trace:
[ 4613.694678]  __switch_to+0xf8/0x17c
[ 4613.698872]  __schedule+0x660/0xee0
[ 4613.703063]  schedule+0xac/0x240
[ 4613.706994]  schedule_timeout+0x500/0x610
[ 4613.711705]  __down+0x128/0x36c
[ 4613.715548]  down+0x240/0x2d0
[ 4613.719221]  hisi_sas_internal_abort_timeout+0x1bc/0x260 [hisi_sas_main]
[ 4613.726618]  sas_execute_internal_abort+0x144/0x310 [libsas]
[ 4613.732976]  sas_execute_internal_abort_dev+0x44/0x60 [libsas]
[ 4613.739504]  hisi_sas_internal_task_abort_dev.isra.0+0xbc/0x1b0 [hisi_sas_main]
[ 4613.747499]  hisi_sas_dev_gone+0x174/0x250 [hisi_sas_main]
[ 4613.753682]  sas_notify_lldd_dev_gone+0xec/0x2e0 [libsas]
[ 4613.759781]  sas_unregister_common_dev+0x4c/0x7a0 [libsas]
[ 4613.765962]  sas_destruct_devices+0xb8/0x120 [libsas]
[ 4613.771709]  sas_do_revalidate_domain.constprop.0+0x1b8/0x31c [libsas]
[ 4613.778930]  sas_revalidate_domain+0x60/0xa4 [libsas]
[ 4613.784716]  process_one_work+0x248/0x950
[ 4613.789424]  worker_thread+0x318/0x934
[ 4613.793878]  kthread+0x190/0x200
[ 4613.797810]  ret_from_fork+0x10/0x18
[ 4613.802121] INFO: task kworker/u256:4:316722 blocked for more than 120 seconds.
[ 4613.816026] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 4613.824538] task:kworker/u256:4  state:D stack:    0 pid:316722 ppid:     2 flags:0x00000208
[ 4613.833670] Workqueue: 0000:74:02.0 hisi_sas_rst_work_handler [hisi_sas_main]
[ 4613.841491] Call trace:
[ 4613.844647]  __switch_to+0xf8/0x17c
[ 4613.848852]  __schedule+0x660/0xee0
[ 4613.853052]  schedule+0xac/0x240
[ 4613.856984]  schedule_timeout+0x500/0x610
[ 4613.861695]  __down+0x128/0x36c
[ 4613.865542]  down+0x240/0x2d0
[ 4613.869216]  hisi_sas_controller_prereset+0x58/0x1fc [hisi_sas_main]
[ 4613.876324]  hisi_sas_rst_work_handler+0x40/0x8c [hisi_sas_main]
[ 4613.883019]  process_one_work+0x248/0x950
[ 4613.887732]  worker_thread+0x318/0x934
[ 4613.892204]  kthread+0x190/0x200
[ 4613.896118]  ret_from_fork+0x10/0x18
[ 4613.900423] INFO: task kworker/u256:1:348985 blocked for more than 121 seconds.
[ 4613.914341] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 4613.922852] task:kworker/u256:1  state:D stack:    0 pid:348985 ppid:     2 flags:0x00000208
[ 4613.931984] Workqueue: 0000:74:02.0_event_q sas_port_event_worker [libsas]
[ 4613.939549] Call trace:
[ 4613.942702]  __switch_to+0xf8/0x17c
[ 4613.946892]  __schedule+0x660/0xee0
[ 4613.951083]  schedule+0xac/0x240
[ 4613.955015]  schedule_timeout+0x500/0x610
[ 4613.959725]  wait_for_common+0x200/0x610
[ 4613.964349]  wait_for_completion+0x3c/0x5c
[ 4613.969146]  flush_workqueue+0x198/0x790
[ 4613.973776]  sas_porte_broadcast_rcvd+0x1e8/0x320 [libsas]
[ 4613.979960]  sas_port_event_worker+0x54/0xa0 [libsas]
[ 4613.985708]  process_one_work+0x248/0x950
[ 4613.990420]  worker_thread+0x318/0x934
[ 4613.994868]  kthread+0x190/0x200
[ 4613.998800]  ret_from_fork+0x10/0x18

This is because when the device goes offline, we obtain the hisi_hba
semaphore and send the ABORT_DEV command to the device. However, the
internal abort timed out due to the 2 bit ECC error and triggers automatic
dump. In addition, since the hisi_hba semaphore has been obtained, the dump
cannot be executed and the controller cannot be reset.

Therefore, the deadlocks occur on the following circular dependencies:
hisi_sas_dev_gone() -> down() -> hisi_sas_internal_task_abort_dev() -> ...
-> hisi_sas_internal_abort_timeout() -> down().

The deadlock is triggered only when the timeout occurs during device goes
offline. To fix this issue, use .rst_ha_timeout to distinguish the scenario
where a device goes offline from other scenarios.

The Linux kernel CVE team has assigned CVE-2024-26873 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 6.7 with commit 2ff07b5c6fe9 and fixed in 6.7.11 with commit e022dd3b8753
	Issue introduced in 6.7 with commit 2ff07b5c6fe9 and fixed in 6.8.2 with commit 85c98073ffcf
	Issue introduced in 6.7 with commit 2ff07b5c6fe9 and fixed in 6.9 with commit 3c4f53b2c341

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-26873
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	drivers/scsi/hisi_sas/hisi_sas_main.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/e022dd3b875315a2d2001a512e98d1dc8c991f4a
	https://git.kernel.org/stable/c/85c98073ffcfe9e46abfb9c66f3364467119d563
	https://git.kernel.org/stable/c/3c4f53b2c341ec6428b98cb51a89a09b025d0953