tracing: Have show_event_filters/triggers files take trace array ref

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The newly added files show_event_filters and show_event_triggers that show
all filters or triggers that are set within the trace array do not take a
reference for the trace array it is showing. Without taking a reference,
the trace_array may be freed via "rmdir" while a task is reading one of
theses files. Those files iterate all the events within an instance
(trace_array) and nothing prevents that instance from being freed while
its data is being read. This causes a use-after-free crash.

Have the open of both those files take the trace_array reference via the
trace_array_get() that prevents the trace_array from being freed while the
files are opened.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260828094153.17b95037@gandalf.local.home
Fixes: 729757b96a ("tracing: Add show_event_filters to expose active event filters")
Fixes: 6a80838814 ("tracing: Add show_event_triggers to expose active event triggers")
Reported-by: Farhad Alemi <farhad.alemi@berkeley.edu>
Closes: https://lore.kernel.org/all/CA+0ovCjerKZJLwXScM9bF2ga2rLi4_XOpUfK41NDbENpeu98jA@mail.gmail.com/
Reviewed-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

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This commit is contained in:

Steven Rostedt 2026-08-28 09:41:53 -04:00

parent cee9395acd

commit f4a771cc68

1 changed files with 24 additions and 4 deletions

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kernel/trace/trace_events.c

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