CVE-2024-26873 scsi: hisi_sas: Fix a deadlock issue related to automatic dump
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
---truncated---
Affected products: vendor: Linux
product: Linux
default_status: unaffected
vendor: Linux
product: Linux
default_status: affected
Published: 2024-04-17T10:27:32.647Z