CVE-2022-50371

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

led: qcom-lpg: Fix sleeping in atomic

lpg_brighness_set() function can sleep, while leds brightness_set() callback must be non-blocking. Change LPG driver to use brightness_set_blocking() instead.

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/0 preempt_count: 101, expected: 0 INFO: lockdep is turned off. CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 6.1.0-rc1-00014-gbe99b089c6fc-dirty #85 Hardware name: Qualcomm Technologies, Inc. DB820c (DT) Call trace: dump_backtrace.part.0+0xe4/0xf0 show_stack+0x18/0x40 dump_stack_lvl+0x88/0xb4 dump_stack+0x18/0x34 __might_resched+0x170/0x254 __might_sleep+0x48/0x9c __mutex_lock+0x4c/0x400 mutex_lock_nested+0x2c/0x40 lpg_brightness_single_set+0x40/0x90 led_set_brightness_nosleep+0x34/0x60 led_heartbeat_function+0x80/0x170 call_timer_fn+0xb8/0x340 __run_timers.part.0+0x20c/0x254 run_timer_softirq+0x3c/0x7c _stext+0x14c/0x578 ____do_softirq+0x10/0x20 call_on_irq_stack+0x2c/0x5c do_softirq_own_stack+0x1c/0x30 __irq_exit_rcu+0x164/0x170 irq_exit_rcu+0x10/0x40 el1_interrupt+0x38/0x50 el1h_64_irq_handler+0x18/0x2c el1h_64_irq+0x64/0x68 cpuidle_enter_state+0xc8/0x380 cpuidle_enter+0x38/0x50 do_idle+0x244/0x2d0 cpu_startup_entry+0x24/0x30 rest_init+0x128/0x1a0 arch_post_acpi_subsys_init+0x0/0x18 start_kernel+0x6f4/0x734 __primary_switched+0xbc/0xc4

Weakness

The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.

Affected Software

Extended Description

Locking is a type of synchronization behavior that ensures that multiple independently-operating processes or threads do not interfere with each other when accessing the same resource. All processes/threads are expected to follow the same steps for locking. If these steps are not followed precisely - or if no locking is done at all - then another process/thread could modify the shared resource in a way that is not visible or predictable to the original process. This can lead to data or memory corruption, denial of service, etc.

Potential Mitigations

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/25.html
• https://cwe.mitre.org/data/definitions/26.html
• https://cwe.mitre.org/data/definitions/27.html

References

• https://git.kernel.org/stable/c/3031993b3474794ecb71b6f969a3e60e4bda9d8a
• https://git.kernel.org/stable/c/380304391fa7fb084745f26b4b9a59f4666520c1
• https://git.kernel.org/stable/c/9deba7b51d5ee7a2d93fabb69f9b8189241f90e3