CVE-2021-47271

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> usb: cdnsp: Fix deadlock issue in cdnsp_thread_irq_handler<br /> <br /> Patch fixes the following critical issue caused by deadlock which has been<br /> detected during testing NCM class:<br /> <br /> smp: csd: Detected non-responsive CSD lock (#1) on CPU#0<br /> smp: csd: CSD lock (#1) unresponsive.<br /> ....<br /> RIP: 0010:native_queued_spin_lock_slowpath+0x61/0x1d0<br /> RSP: 0018:ffffbc494011cde0 EFLAGS: 00000002<br /> RAX: 0000000000000101 RBX: ffff9ee8116b4a68 RCX: 0000000000000000<br /> RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9ee8116b4658<br /> RBP: ffffbc494011cde0 R08: 0000000000000001 R09: 0000000000000000<br /> R10: ffff9ee8116b4670 R11: 0000000000000000 R12: ffff9ee8116b4658<br /> R13: ffff9ee8116b4670 R14: 0000000000000246 R15: ffff9ee8116b4658<br /> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> CR2: 00007f7bcc41a830 CR3: 000000007a612003 CR4: 00000000001706e0<br /> Call Trace:<br /> <br /> do_raw_spin_lock+0xc0/0xd0<br /> _raw_spin_lock_irqsave+0x95/0xa0<br /> cdnsp_gadget_ep_queue.cold+0x88/0x107 [cdnsp_udc_pci]<br /> usb_ep_queue+0x35/0x110<br /> eth_start_xmit+0x220/0x3d0 [u_ether]<br /> ncm_tx_timeout+0x34/0x40 [usb_f_ncm]<br /> ? ncm_free_inst+0x50/0x50 [usb_f_ncm]<br /> __hrtimer_run_queues+0xac/0x440<br /> hrtimer_run_softirq+0x8c/0xb0<br /> __do_softirq+0xcf/0x428<br /> asm_call_irq_on_stack+0x12/0x20<br /> <br /> do_softirq_own_stack+0x61/0x70<br /> irq_exit_rcu+0xc1/0xd0<br /> sysvec_apic_timer_interrupt+0x52/0xb0<br /> asm_sysvec_apic_timer_interrupt+0x12/0x20<br /> RIP: 0010:do_raw_spin_trylock+0x18/0x40<br /> RSP: 0018:ffffbc494138bda8 EFLAGS: 00000246<br /> RAX: 0000000000000000 RBX: ffff9ee8116b4658 RCX: 0000000000000000<br /> RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9ee8116b4658<br /> RBP: ffffbc494138bda8 R08: 0000000000000001 R09: 0000000000000000<br /> R10: ffff9ee8116b4670 R11: 0000000000000000 R12: ffff9ee8116b4658<br /> R13: ffff9ee8116b4670 R14: ffff9ee7b5c73d80 R15: ffff9ee8116b4000<br /> _raw_spin_lock+0x3d/0x70<br /> ? cdnsp_thread_irq_handler.cold+0x32/0x112c [cdnsp_udc_pci]<br /> cdnsp_thread_irq_handler.cold+0x32/0x112c [cdnsp_udc_pci]<br /> ? cdnsp_remove_request+0x1f0/0x1f0 [cdnsp_udc_pci]<br /> ? cdnsp_thread_irq_handler+0x5/0xa0 [cdnsp_udc_pci]<br /> ? irq_thread+0xa0/0x1c0<br /> irq_thread_fn+0x28/0x60<br /> irq_thread+0x105/0x1c0<br /> ? __kthread_parkme+0x42/0x90<br /> ? irq_forced_thread_fn+0x90/0x90<br /> ? wake_threads_waitq+0x30/0x30<br /> ? irq_thread_check_affinity+0xe0/0xe0<br /> kthread+0x12a/0x160<br /> ? kthread_park+0x90/0x90<br /> ret_from_fork+0x22/0x30<br /> <br /> The root cause of issue is spin_lock/spin_unlock instruction instead<br /> spin_lock_irqsave/spin_lock_irqrestore in cdnsp_thread_irq_handler<br /> function.