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>

2 files changed, 49 insertions, 0 deletions

diff --git a/Documentation/driver-api/xilinx/eemi.rst b/Documentation/driver-api/xilinx/eemi.rst
new file mode 100644
index 000000000..c1bc47b90
--- /dev/null
+++ b/Documentation/driver-api/xilinx/eemi.rst
@@ -0,0 +1,40 @@
+====================================
+Xilinx Zynq MPSoC EEMI Documentation
+====================================
+
+Xilinx Zynq MPSoC Firmware Interface
+-------------------------------------
+The zynqmp-firmware node describes the interface to platform firmware.
+ZynqMP has an interface to communicate with secure firmware. Firmware
+driver provides an interface to firmware APIs. Interface APIs can be
+used by any driver to communicate with PMC(Platform Management Controller).
+
+Embedded Energy Management Interface (EEMI)
+----------------------------------------------
+The embedded energy management interface is used to allow software
+components running across different processing clusters on a chip or
+device to communicate with a power management controller (PMC) on a
+device to issue or respond to power management requests.
+
+Any driver who wants to communicate with PMC using EEMI APIs use the
+functions provided for each function.
+
+IOCTL
+------
+IOCTL API is for device control and configuration. It is not a system
+IOCTL but it is an EEMI API. This API can be used by master to control
+any device specific configuration. IOCTL definitions can be platform
+specific. This API also manage shared device configuration.
+
+The following IOCTL IDs are valid for device control:
+- IOCTL_SET_PLL_FRAC_MODE	8
+- IOCTL_GET_PLL_FRAC_MODE	9
+- IOCTL_SET_PLL_FRAC_DATA	10
+- IOCTL_GET_PLL_FRAC_DATA	11
+
+Refer EEMI API guide [0] for IOCTL specific parameters and other EEMI APIs.
+
+References
+----------
+[0] Embedded Energy Management Interface (EEMI) API guide:
+    https://www.xilinx.com/support/documentation/user_guides/ug1200-eemi-api.pdf
diff --git a/Documentation/driver-api/xilinx/index.rst b/Documentation/driver-api/xilinx/index.rst
new file mode 100644
index 000000000..c95bda55d
--- /dev/null
+++ b/Documentation/driver-api/xilinx/index.rst
@@ -0,0 +1,9 @@
+
+===========
+Xilinx FPGA
+===========
+
+.. toctree::
+    :maxdepth: 1
+
+    eemi