CVE-2026-68146

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ftrace: Add global mutex to serialize trace_parser access<br /> <br /> In ftrace, the trace_parser structure is allocated and initialized when<br /> a trace file is opened, and is subsequently used across write and release<br /> handlers to parse user input.<br /> <br /> The affected handler paths and their specific functions are:<br /> - Open paths: ftrace_regex_open(), ftrace_graph_open()<br /> - Write paths: ftrace_regex_write(), ftrace_graph_write()<br /> - Release paths: ftrace_regex_release(), ftrace_graph_release()<br /> <br /> If userspace opens a trace file descriptor and shares it across multiple<br /> threads, concurrent write calls will race on the parser&amp;#39;s internal state,<br /> specifically the &amp;#39;idx&amp;#39;, &amp;#39;cont&amp;#39;, and &amp;#39;buffer&amp;#39; fields, leading to corrupted<br /> input or undefined behavior.<br /> <br /> Fix this by adding a global mutex, parser_lock, to serialize all access<br /> to trace_parser across write and release paths, preventing concurrent<br /> corruption of parser state.