CVE-2021-47271
MediumIn the Linux kernel, the following vulnerability has been resolved: usb: cdnsp: Fix deadlock issue in cdnsp_thread_irq_handler Patch fixes the following critical issue caused by deadlock which has been detected during testing NCM class: smp: csd: Detected non-responsive CSD lock (#1) on CPU#0 smp: csd: CSD lock (#1) unresponsive. .... RIP: 0010:native_queued_spin_lock_slowpath+0x61/0x1d0 RSP: 0018:ffffbc494011cde0 EFLAGS: 00000002 RAX: 0000000000000101 RBX: ffff9ee8116b4a68 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9ee8116b4658 RBP: ffffbc494011cde0 R08: 0000000000000001 R09: 0000000000000000 R10: ffff9ee8116b4670 R11: 0000000000000000 R12: ffff9ee8116b4658 R13: ffff9ee8116b4670 R14: 0000000000000246 R15: ffff9ee8116b4658 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7bcc41a830 CR3: 000000007a612003 CR4: 00000000001706e0 Call Trace: <IRQ> do_raw_spin_lock+0xc0/0xd0 _raw_spin_lock_irqsave+0x95/0xa0 cdnsp_gadget_ep_queue.cold+0x88/0x107 [cdnsp_udc_pci] usb_ep_queue+0x35/0x110 eth_start_xmit+0x220/0x3d0 [u_ether] ncm_tx_timeout+0x34/0x40 [usb_f_ncm] ? ncm_free_inst+0x50/0x50 [usb_f_ncm] __hrtimer_run_queues+0xac/0x440 hrtimer_run_softirq+0x8c/0xb0 __do_softirq+0xcf/0x428 asm_call_irq_on_stack+0x12/0x20 </IRQ> do_softirq_own_stack+0x61/0x70 irq_exit_rcu+0xc1/0xd0 sysvec_apic_timer_interrupt+0x52/0xb0 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:do_raw_spin_trylock+0x18/0x40 RSP: 0018:ffffbc494138bda8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff9ee8116b4658 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9ee8116b4658 RBP: ffffbc494138bda8 R08: 0000000000000001 R09: 0000000000000000 R10: ffff9ee8116b4670 R11: 0000000000000000 R12: ffff9ee8116b4658 R13: ffff9ee8116b4670 R14: ffff9ee7b5c73d80 R15: ffff9ee8116b4000 _raw_spin_lock+0x3d/0x70 ? cdnsp_thread_irq_handler.cold+0x32/0x112c [cdnsp_udc_pci] cdnsp_thread_irq_handler.cold+0x32/0x112c [cdnsp_udc_pci] ? cdnsp_remove_request+0x1f0/0x1f0 [cdnsp_udc_pci] ? cdnsp_thread_irq_handler+0x5/0xa0 [cdnsp_udc_pci] ? irq_thread+0xa0/0x1c0 irq_thread_fn+0x28/0x60 irq_thread+0x105/0x1c0 ? __kthread_parkme+0x42/0x90 ? irq_forced_thread_fn+0x90/0x90 ? wake_threads_waitq+0x30/0x30 ? irq_thread_check_affinity+0xe0/0xe0 kthread+0x12a/0x160 ? kthread_park+0x90/0x90 ret_from_fork+0x22/0x30 The root cause of issue is spin_lock/spin_unlock instruction instead spin_lock_irqsave/spin_lock_irqrestore in cdnsp_thread_irq_handler function.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-667CVE-2021-47271 is a Improper Locking vulnerability
What is Improper Locking?
The product does not properly acquire or release a lock, which can lead to unexpected behaviour. Learn more on MITRE CWE
References
The following references provide additional information about CVE-2021-47271 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/a9aecef198faae3240921b707bc09b602e966fce
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PatchKernel patch commithttps://git.kernel.org/stable/c/ae746b6f4ce619cf4032fd798a232b010907a397
Frequently asked questions
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What is CVE-2021-47271?
CVE-2021-47271 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as an Improper Locking flaw (CWE-667) . CVE-2021-47271 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2021-47271?
CVE-2021-47271 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2021-47271?
No patch is currently available for CVE-2021-47271. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
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Is CVE-2021-47271 actively exploited?
No — CVE-2021-47271 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Improper Locking (CWE-667)?
The product does not properly acquire or release a lock, which can lead to unexpected behaviour. View CWE-667 on MITRE CWE →