selftests/bpf: Test packet range of pointers sharing an idgrafted

Add tests where two packet pointers share an id and tightening one
pointer's umax from its var_off would put it less than their constant
distance from the other's umax: with an index & 0x38 capped at 50, the
base pointer keeps umax 50, so the pointer 8 bytes further on must keep
umax 58, even though its known bits allow at most 56.

These refused a valid program or accepted an out-of-bounds access before
the fix:

- check the advanced copy, load through the base: valid, was refused;
- check the base, load the byte at base + 1 through a copy advanced by
  8: was accepted;
- check base + 4, load 4 bytes at base + 2 through base + 8: reads two
  bytes past the checked range, was accepted;
- the same as the second with data_meta pointers checked against data:
  was accepted.

These pass with and without the fix and cover nearby paths:

- subtract an unknown scalar from a checked pointer and load below it
  (the range is kept across a new id);
- reach a load through two paths whose checks cover 8 and 7 bytes after
  the loaded pointer; the second path must not be pruned by the first;
- spill a copy of a pointer, check the pointer, fill the copy and load
  one byte past the checked range: the load is refused, and the copy
  has the range of the check.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/cache/Kconfig b/drivers/cache/Kconfig
new file mode 100644
index 000000000..1518449d4
--- /dev/null
+++ b/drivers/cache/Kconfig
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0
+
+menuconfig CACHEMAINT_FOR_DMA
+	bool "Cache management for noncoherent DMA"
+	depends on RISCV
+	default y
+	help
+	  These drivers implement support for noncoherent DMA master devices
+	  on platforms that lack the standard CPU interfaces for this.
+
+if CACHEMAINT_FOR_DMA
+
+config AX45MP_L2_CACHE
+	bool "Andes Technology AX45MP L2 Cache controller"
+	select RISCV_NONSTANDARD_CACHE_OPS
+	help
+	  Support for the L2 cache controller on Andes Technology AX45MP platforms.
+
+config SIFIVE_CCACHE
+	bool "Sifive Composable Cache controller"
+	depends on ARCH_SIFIVE || ARCH_STARFIVE
+	help
+	  Support for the composable cache controller on SiFive platforms.
+
+config STARFIVE_STARLINK_CACHE
+	bool "StarFive StarLink Cache controller"
+	depends on ARCH_STARFIVE
+	depends on 64BIT
+	select RISCV_DMA_NONCOHERENT
+	select RISCV_NONSTANDARD_CACHE_OPS
+	help
+	  Support for the StarLink cache controller IP from StarFive.
+
+endif #CACHEMAINT_FOR_DMA
+
+menuconfig CACHEMAINT_FOR_HOTPLUG
+	bool "Cache management for memory hot plug like operations"
+	depends on GENERIC_CPU_CACHE_MAINTENANCE
+	help
+	  These drivers implement cache management for flows where it is necessary
+	  to flush data from all host caches.
+
+if CACHEMAINT_FOR_HOTPLUG
+
+config HISI_SOC_HHA
+	tristate "HiSilicon Hydra Home Agent (HHA) device driver"
+	depends on (ARM64 && ACPI) || COMPILE_TEST
+	help
+	  The Hydra Home Agent (HHA) is responsible for cache coherency
+	  on the SoC. This drivers enables the cache maintenance functions of
+	  the HHA.
+
+	  This driver can be built as a module. If so, the module will be
+	  called hisi_soc_hha.
+
+endif #CACHEMAINT_FOR_HOTPLUG