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, 56 insertions, 0 deletions

diff --git a/drivers/scsi/smartpqi/Kconfig b/drivers/scsi/smartpqi/Kconfig
new file mode 100644
index 000000000..789460b0a
--- /dev/null
+++ b/drivers/scsi/smartpqi/Kconfig
@@ -0,0 +1,56 @@
+#
+# Kernel configuration file for the SMARTPQI
+#
+# Copyright (c) 2019-2023 Microchip Technology Inc. and its subsidiaries
+# Copyright (c) 2017-2018 Microsemi Corporation
+# Copyright (c) 2016 Microsemi Corporation
+# Copyright (c) 2016 PMC-Sierra, Inc.
+#  (mailto:storagedev@microchip.com)
+
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; version 2
+# of the License.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# NO WARRANTY
+# THE PROGRAM IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR
+# CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT
+# LIMITATION, ANY WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT,
+# MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Each Recipient is
+# solely responsible for determining the appropriateness of using and
+# distributing the Program and assumes all risks associated with its
+# exercise of rights under this Agreement, including but not limited to
+# the risks and costs of program errors, damage to or loss of data,
+# programs or equipment, and unavailability or interruption of operations.
+
+# DISCLAIMER OF LIABILITY
+# NEITHER RECIPIENT NOR ANY CONTRIBUTORS SHALL HAVE ANY LIABILITY FOR ANY
+# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS), HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+# TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+# USE OR DISTRIBUTION OF THE PROGRAM OR THE EXERCISE OF ANY RIGHTS GRANTED
+# HEREUNDER, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES
+
+config SCSI_SMARTPQI
+	tristate "Microchip PQI Driver"
+	depends on PCI && SCSI && !S390
+	select SCSI_SAS_ATTRS
+	select RAID_ATTRS
+	help
+	This driver supports Microchip PQI controllers.
+
+	<http://www.microchip.com>
+
+	To compile this driver as a module, choose M here: the
+	module will be called smartpqi.
+
+        Note: the aacraid driver will not manage a smartpqi
+              controller. You need to enable smartpqi for smartpqi
+              controllers. For more information, please see
+              Documentation/scsi/smartpqi.rst