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, 29 insertions, 0 deletions

diff --git a/sound/isa/sb/Makefile b/sound/isa/sb/Makefile
new file mode 100644
index 000000000..96a926feb
--- /dev/null
+++ b/sound/isa/sb/Makefile
@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for ALSA
+# Copyright (c) 2001 by Jaroslav Kysela <perex@perex.cz>
+#
+
+snd-sb-common-y := sb_common.o sb_mixer.o
+snd-sb8-dsp-y := sb8_main.o sb8_midi.o
+snd-sb16-dsp-y := sb16_main.o
+snd-sb16-csp-y := sb16_csp.o
+snd-sb8-y := sb8.o
+snd-sb16-y := sb16.o
+snd-sbawe-y := sbawe.o emu8000.o
+snd-emu8000-synth-y := emu8000_synth.o emu8000_callback.o emu8000_patch.o emu8000_pcm.o
+snd-jazz16-y := jazz16.o
+
+# Toplevel Module Dependency
+obj-$(CONFIG_SND_SB_COMMON) += snd-sb-common.o
+obj-$(CONFIG_SND_SB16_DSP) += snd-sb16-dsp.o
+obj-$(CONFIG_SND_SB8_DSP) += snd-sb8-dsp.o
+obj-$(CONFIG_SND_SB8) += snd-sb8.o
+obj-$(CONFIG_SND_SB16) += snd-sb16.o
+obj-$(CONFIG_SND_SBAWE) += snd-sbawe.o
+obj-$(CONFIG_SND_JAZZ16) += snd-jazz16.o
+ifeq ($(CONFIG_SND_SB16_CSP),y)
+  obj-$(CONFIG_SND_SB16) += snd-sb16-csp.o
+  obj-$(CONFIG_SND_SBAWE) += snd-sb16-csp.o
+endif
+obj-$(CONFIG_SND_SBAWE_SEQ) += snd-emu8000-synth.o