CVE-2025-21820
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2025
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
tty: xilinx_uartps: split sysrq handling
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.
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
unaffected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 74ea66d4ca061a3cd4c0e924e51b60e924644852 | affected | git | e22a97700901ba5e8bf8db68056a0d50f9440cae | Unavailable | None listed |
| 74ea66d4ca061a3cd4c0e924e51b60e924644852 | affected | git | de5bd24197bd9ee37ec1e379a3d882bbd15c5065 | Unavailable | None listed |
| 74ea66d4ca061a3cd4c0e924e51b60e924644852 | affected | git | 8ea0e7b3d7b8f2f0fc9db491ff22a0abe120801c | Unavailable | None listed |
| 74ea66d4ca061a3cd4c0e924e51b60e924644852 | affected | git | 9b88a7c4584ba67267a051069b8abe44fc9595b2 | Unavailable | None listed |
| 74ea66d4ca061a3cd4c0e924e51b60e924644852 | affected | git | 4410dba9807a17a93f649a9f5870ceaf30a675a3 | Unavailable | None listed |
| 74ea66d4ca061a3cd4c0e924e51b60e924644852 | affected | git | b06f388994500297bb91be60ffaf6825ecfd2afe | Unavailable | None listed |
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
affected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 4.6 | affected | Unavailable | Unavailable | Unavailable | None listed |
| 0 | unaffected | semver | 4.6 | Unavailable | None listed |
| 5.15.179 | unaffected | semver | Unavailable | 5.15.* | None listed |
| 6.1.129 | unaffected | semver | Unavailable | 6.1.* | None listed |
| 6.6.78 | unaffected | semver | Unavailable | 6.6.* | None listed |
| 6.12.14 | unaffected | semver | Unavailable | 6.12.* | None listed |
| 6.13.3 | unaffected | semver | Unavailable | 6.13.* | None listed |
| 6.14 | unaffected | original_commit_for_fix | Unavailable | * | None listed |