Steven Rostedt 4d11fac941 tracing: Verify event formats that have "%*p.." ... [ Upstream commit ea8d7647f9 ] The trace event verifier checks the formats of trace events to make sure that they do not point at memory that is not in the trace event itself or in data that will never be freed. If an event references data that was allocated when the event triggered and that same data is freed before the event is read, then the kernel can crash by reading freed memory. The verifier runs at boot up (or module load) and scans the print formats of the events and checks their arguments to make sure that dereferenced pointers are safe. If the format uses "%*p.." the verifier will ignore it, and that could be dangerous. Cover this case as well. Also add to the sample code a use case of "%*pbl". Link: https://lore.kernel.org/all/bcba4d76-2c3f-4d11-baf0-02905db953dd@oracle.com/ Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Fixes: 5013f454a3 ("tracing: Add check of trace event print fmts for dereferencing pointers") Link: https://lore.kernel.org/20250327195311.2d89ec66@gandalf.local.home Reported-by: Libo Chen <libo.chen@oracle.com> Reviewed-by: Libo Chen <libo.chen@oracle.com> Tested-by: Libo Chen <libo.chen@oracle.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2025-05-02 07:50:37 +02:00
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Makefile	tracing: Add TRACE_CUSTOM_EVENT() macro	2022-03-11 11:49:24 -05:00
trace_custom_sched.c	tracing: Add TRACE_CUSTOM_EVENT() macro	2022-03-11 11:49:24 -05:00
trace_custom_sched.h	sched/tracing: Append prev_state to tp args instead	2022-05-12 00:37:11 +02:00
trace-events-sample.c	tracing: Add __cpumask to denote a trace event field that is a cpumask_t	2022-11-23 19:08:30 -05:00
trace-events-sample.h	tracing: Verify event formats that have "%*p.."	2025-05-02 07:50:37 +02:00