CVE-2022-49767: 
Linux Kernel vulnerability analysis and mitigation

CVE-2022-49767 is a vulnerability in the Linux kernel affecting the 9p filesystem transport layer. The vulnerability was disclosed on May 1, 2025, and impacts the Linux kernel's 9p filesystem implementation, specifically related to the handling of O_NONBLOCK flags during file operations (NVD, Wiz).

The vulnerability occurs when p9_mux_poll_stop() from p9_conn_destroy() from p9_fd_close() fails to interrupt already started kernel_read() from p9_fd_read() from p9_read_work() and/or kernel_write() from p9_fd_write() from p9_write_work() requests. While p9_socket_open() sets O_NONBLOCK flag, p9_fd_open() does not, causing pipe blocks unless a signal is pending. The vulnerability has been assigned a CVSS v3.1 Base Score of 5.5, indicating moderate severity (Red Hat).

The vulnerability can lead to system hangs during file operations using the 9p filesystem transport layer. This primarily affects systems using the 9p filesystem for file sharing or virtualization purposes (NVD).

The vulnerability has been resolved by modifying the 9p/trans_fd component to always use O_NONBLOCK for read/write operations. This ensures that pipe operations don't block indefinitely during file operations (NVD).