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, 37 insertions, 0 deletions

diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile
new file mode 100644
index 000000000..01745eca1
--- /dev/null
+++ b/drivers/mtd/maps/Makefile
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# linux/drivers/maps/Makefile
+#
+
+ifeq ($(CONFIG_MTD_COMPLEX_MAPPINGS),y)
+obj-$(CONFIG_MTD)		+= map_funcs.o
+endif
+
+# Chip mappings
+obj-$(CONFIG_MTD_CFI_FLAGADM)	+= cfi_flagadm.o
+obj-$(CONFIG_MTD_DC21285)	+= dc21285.o
+obj-$(CONFIG_MTD_L440GX)	+= l440gx.o
+obj-$(CONFIG_MTD_AMD76XROM)	+= amd76xrom.o
+obj-$(CONFIG_MTD_ESB2ROM)	+= esb2rom.o
+obj-$(CONFIG_MTD_ICHXROM)	+= ichxrom.o
+obj-$(CONFIG_MTD_CK804XROM)	+= ck804xrom.o
+obj-$(CONFIG_MTD_TSUNAMI)	+= tsunami_flash.o
+obj-$(CONFIG_MTD_PXA2XX)	+= pxa2xx-flash.o
+obj-$(CONFIG_MTD_PHYSMAP)	+= physmap.o
+physmap-y			:= physmap-core.o
+physmap-$(CONFIG_MTD_PHYSMAP_VERSATILE) += physmap-versatile.o
+physmap-$(CONFIG_MTD_PHYSMAP_GEMINI) += physmap-gemini.o
+physmap-$(CONFIG_MTD_PHYSMAP_IXP4XX) += physmap-ixp4xx.o
+obj-$(CONFIG_MTD_PISMO)		+= pismo.o
+obj-$(CONFIG_MTD_PCMCIA)	+= pcmciamtd.o
+obj-$(CONFIG_MTD_SA1100)	+= sa1100-flash.o
+obj-$(CONFIG_MTD_SBC_GXX)	+= sbc_gxx.o
+obj-$(CONFIG_MTD_SUN_UFLASH)	+= sun_uflash.o
+obj-$(CONFIG_MTD_SCx200_DOCFLASH)+= scx200_docflash.o
+obj-$(CONFIG_MTD_SOLUTIONENGINE)+= solutionengine.o
+obj-$(CONFIG_MTD_PCI)		+= pci.o
+obj-$(CONFIG_MTD_UCLINUX)	+= uclinux.o
+obj-$(CONFIG_MTD_SCB2_FLASH)	+= scb2_flash.o
+obj-$(CONFIG_MTD_PLATRAM)	+= plat-ram.o
+obj-$(CONFIG_MTD_VMU)		+= vmu-flash.o
+obj-$(CONFIG_MTD_LANTIQ)	+= lantiq-flash.o