CVE-2024-41036

2024-07-2915:15:12

Google

osv.dev

cve-2024-41036

linux kernel

deadlock

spinlocks

smp

soft lockup

tx queue

vulnerability

CVSS3

5.5

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

AI Score

6.1

Confidence

High

EPSS

Percentile

5.1%

JSON

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

net: ks8851: Fix deadlock with the SPI chip variant

When SMP is enabled and spinlocks are actually functional then there is
a deadlock with the ‘statelock’ spinlock between ks8851_start_xmit_spi
and ks8851_irq:

watchdog: BUG: soft lockup - CPU#0 stuck for 27s!
call trace:
  queued_spin_lock_slowpath+0x100/0x284
  do_raw_spin_lock+0x34/0x44
  ks8851_start_xmit_spi+0x30/0xb8
  ks8851_start_xmit+0x14/0x20
  netdev_start_xmit+0x40/0x6c
  dev_hard_start_xmit+0x6c/0xbc
  sch_direct_xmit+0xa4/0x22c
  __qdisc_run+0x138/0x3fc
  qdisc_run+0x24/0x3c
  net_tx_action+0xf8/0x130
  handle_softirqs+0x1ac/0x1f0
  __do_softirq+0x14/0x20
  ____do_softirq+0x10/0x1c
  call_on_irq_stack+0x3c/0x58
  do_softirq_own_stack+0x1c/0x28
  __irq_exit_rcu+0x54/0x9c
  irq_exit_rcu+0x10/0x1c
  el1_interrupt+0x38/0x50
  el1h_64_irq_handler+0x18/0x24
  el1h_64_irq+0x64/0x68
  __netif_schedule+0x6c/0x80
  netif_tx_wake_queue+0x38/0x48
  ks8851_irq+0xb8/0x2c8
  irq_thread_fn+0x2c/0x74
  irq_thread+0x10c/0x1b0
  kthread+0xc8/0xd8
  ret_from_fork+0x10/0x20

This issue has not been identified earlier because tests were done on
a device with SMP disabled and so spinlocks were actually NOPs.

Now use spin_(un)lock_bh for TX queue related locking to avoid execution
of softirq work synchronously that would lead to a deadlock.