selftests/bpf: Reject graph kptr use after RCU unlockgrafted

Add a sleepable verifier test that loads a graph-node local kptr in an
explicit RCU read-side critical section, then passes its node to
bpf_rbtree_remove() after the section ends.

Before the verifier fix, the stale NON_OWN_REF flag makes the node look like
a live borrowed reference and the program is accepted. After the fix, the
pointer is demoted without NON_OWN_REF and the graph kfunc argument is
rejected.

Also exercise a graph kptr loaded while a spin lock provides implicit RCU
protection. The pointer must be invalidated when the lock is released, which
guards the required ordering between non-owning-reference invalidation and
RCU demotion.

Update the existing fault-protected load test state description. The
post-unlock pointer no longer carries NON_OWN_REF, but remains readable
because the load is rewritten to use BPF_PROBE_MEM.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/tools/lib/thermal/libthermal.map b/tools/lib/thermal/libthermal.map
new file mode 100644
index 000000000..1d3d0c04e
--- /dev/null
+++ b/tools/lib/thermal/libthermal.map
@@ -0,0 +1,33 @@
+LIBTHERMAL_0.0.1 {
+	global:
+		for_each_thermal_zone;
+		for_each_thermal_trip;
+		for_each_thermal_cdev;
+		for_each_thermal_threshold;
+		thermal_zone_find_by_name;
+		thermal_zone_find_by_id;
+		thermal_zone_discover;
+		thermal_init;
+		thermal_exit;
+		thermal_events_exit;
+		thermal_events_init;
+		thermal_events_handle;
+		thermal_events_fd;
+		thermal_cmd_exit;
+		thermal_cmd_init;
+		thermal_cmd_get_tz;
+		thermal_cmd_get_cdev;
+		thermal_cmd_get_trip;
+		thermal_cmd_get_governor;
+		thermal_cmd_get_temp;
+		thermal_cmd_threshold_get;
+		thermal_cmd_threshold_add;
+		thermal_cmd_threshold_delete;
+		thermal_cmd_threshold_flush;
+		thermal_sampling_exit;
+		thermal_sampling_init;
+		thermal_sampling_handle;
+		thermal_sampling_fd;
+local:
+		*;
+};