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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-21820 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: tty: xilinx_uartps: split sysrq handling lockdep detects the following circular locking dependency: CPU 0 CPU 1 ========================== ============================ cdns_uart_isr() printk() uart_port_lock(port) console_lock() cdns_uart_console_write() if (!port->sysrq) uart_port_lock(port) uart_handle_break() port->sysrq = ... uart_handle_sysrq_char() printk() console_lock() The fixed commit attempts to avoid this situation by only taking the port lock in cdns_uart_console_write if port->sysrq unset. However, if (as shown above) cdns_uart_console_write runs before port->sysrq is set, then it will try to take the port lock anyway. This may result in a deadlock. Fix this by splitting sysrq handling into two parts. We use the prepare helper under the port lock and defer handling until we release the lock.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://git.kernel.org/stable/c/4410dba9807a17a93f649a9f5870ceaf30a675a3 Patch 
https://git.kernel.org/stable/c/8ea0e7b3d7b8f2f0fc9db491ff22a0abe120801c Patch 
https://git.kernel.org/stable/c/9b88a7c4584ba67267a051069b8abe44fc9595b2 Patch 
https://git.kernel.org/stable/c/b06f388994500297bb91be60ffaf6825ecfd2afe Patch 
https://git.kernel.org/stable/c/de5bd24197bd9ee37ec1e379a3d882bbd15c5065 Patch 
https://git.kernel.org/stable/c/e22a97700901ba5e8bf8db68056a0d50f9440cae

Weakness Enumeration

CWE-ID CWE Name Source
CWE-667 Improper Locking cwe source acceptance level NIST  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

3 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-21820
NVD Published Date:
02/27/2025
NVD Last Modified:
03/13/2025
Source:
kernel.org