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, 74 insertions, 0 deletions

diff --git a/sound/soc/codecs/ics43432.c b/sound/soc/codecs/ics43432.c
new file mode 100644
index 000000000..58a382254
--- /dev/null
+++ b/sound/soc/codecs/ics43432.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * I2S MEMS microphone driver for InvenSense ICS-43432 and similar
+ * MEMS-based microphones.
+ *
+ * - Non configurable.
+ * - I2S interface, 64 BCLs per frame, 32 bits per channel, 24 bit data
+ *
+ * Copyright (c) 2015 Axis Communications AB
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/initval.h>
+#include <sound/tlv.h>
+
+#define ICS43432_RATE_MIN 7190 /* Hz, from data sheet */
+#define ICS43432_RATE_MAX 52800  /* Hz, from data sheet */
+
+#define ICS43432_FORMATS (SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32)
+
+static struct snd_soc_dai_driver ics43432_dai = {
+	.name = "ics43432-hifi",
+	.capture = {
+		.stream_name = "Capture",
+		.channels_min = 1,
+		.channels_max = 2,
+		.rate_min = ICS43432_RATE_MIN,
+		.rate_max = ICS43432_RATE_MAX,
+		.rates = SNDRV_PCM_RATE_CONTINUOUS,
+		.formats = ICS43432_FORMATS,
+	},
+};
+
+static const struct snd_soc_component_driver ics43432_component_driver = {
+	.idle_bias_on		= 1,
+	.use_pmdown_time	= 1,
+	.endianness		= 1,
+};
+
+static int ics43432_probe(struct platform_device *pdev)
+{
+	return devm_snd_soc_register_component(&pdev->dev,
+			&ics43432_component_driver,
+			&ics43432_dai, 1);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id ics43432_ids[] = {
+	{ .compatible = "invensense,ics43432", },
+	{ .compatible = "cui,cmm-4030d-261", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ics43432_ids);
+#endif
+
+static struct platform_driver ics43432_driver = {
+	.driver = {
+		.name = "ics43432",
+		.of_match_table = of_match_ptr(ics43432_ids),
+	},
+	.probe = ics43432_probe,
+};
+
+module_platform_driver(ics43432_driver);
+
+MODULE_DESCRIPTION("ASoC ICS43432 driver");
+MODULE_AUTHOR("Ricard Wanderlof <ricardw@axis.com>");
+MODULE_LICENSE("GPL v2");