From 33a154a96e71a34a1bcca9f40da343dbbf7b38b4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 1 Oct 2026 14:52:55 +0000 Subject: selftests/bpf: Test packet range of pointers sharing an id 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 Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- scripts/gcc-plugins/Kconfig | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 scripts/gcc-plugins/Kconfig (limited to 'scripts/gcc-plugins/Kconfig') diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig new file mode 100644 index 000000000..6b34ba193 --- /dev/null +++ b/scripts/gcc-plugins/Kconfig @@ -0,0 +1,39 @@ +# SPDX-License-Identifier: GPL-2.0-only +config HAVE_GCC_PLUGINS + bool + help + An arch should select this symbol if it supports building with + GCC plugins. + +menuconfig GCC_PLUGINS + bool "GCC plugins" + depends on HAVE_GCC_PLUGINS + depends on CC_IS_GCC + depends on $(success,test -e $(shell,$(CC) -print-file-name=plugin)/include/plugin-version.h) + default y + help + GCC plugins are loadable modules that provide extra features to the + compiler. They are useful for runtime instrumentation and static analysis. + + See Documentation/kbuild/gcc-plugins.rst for details. + +if GCC_PLUGINS + +config GCC_PLUGIN_LATENT_ENTROPY + bool "Generate some entropy during boot and runtime" + help + By saying Y here the kernel will instrument some kernel code to + extract some entropy from both original and artificially created + program state. This will help especially embedded systems where + there is little 'natural' source of entropy normally. The cost + is some slowdown of the boot process (about 0.5%) and fork and + irq processing. + + Note that entropy extracted this way is not cryptographically + secure! + + This plugin was ported from grsecurity/PaX. More information at: + * https://grsecurity.net/ + * https://pax.grsecurity.net/ + +endif -- cgit v1.3.1