From: Ondrej Mosnacek omosnace@redhat.com

This file defines both read and write operations, yet it is being created as read-only. This means that it can't be written to without the CAP_DAC_OVERRIDE capability. Fix the permissions to allow root to write to it without the need to override DAC perms.

Link: https://lore.kernel.org/linux-trace-kernel/20230503140114.3280002-1-omosnace...

Cc: stable@vger.kernel.org Cc: Masami Hiramatsu mhiramat@kernel.org Fixes: 03329f993978 ("tracing: Add tracefs file buffer_percentage") Signed-off-by: Ondrej Mosnacek omosnace@redhat.com Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org --- kernel/trace/trace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 076d893d2965..b9be1af23a73 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -9660,7 +9660,7 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)

tr->buffer_percent = 50;

- trace_create_file("buffer_percent", TRACE_MODE_READ, d_tracer, + trace_create_file("buffer_percent", TRACE_MODE_WRITE, d_tracer, tr, &buffer_percent_fops);

create_trace_options_dir(tr);