Tracker / CVE-2025-21820
CVE-2025-21820
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.
Prodotti e versioni affette
| linux | linux_kernel · 4.6 → 6.1.129 |
|---|---|
| linux | linux_kernel · 6.13 → 6.13.3 |
| linux | linux_kernel · 6.2 → 6.6.78 |
| linux | linux_kernel · 6.7 → 6.12.14 |