From 2b97956af60810cd382b86b9ce9aea421b889861 Mon Sep 17 00:00:00 2001 From: Nuoqi Gui Date: Fri, 4 Sep 2026 12:41:55 +0200 Subject: selftests/bpf: Test rhtab kptr cancellation semantics Resizable hash-map updates and deletions must not perform full special-field destruction in their caller context. In particular, a referenced kptr must remain attached to the allocation until the memory allocator destructor can release it safely. Add separate coverage for both affected paths. The update test stores a task kptr, replaces the ordinary value bytes with BPF_EXIST, and verifies that the kptr survived. The delete test removes an element and exchanges its kptr through the still-valid map-value pointer before the allocation is reclaimed. Both cases observe a NULL kptr when rhtab uses bpf_obj_free_fields(). They recover and release the reference after rhtab switches to cancellation semantics. Signed-off-by: Nuoqi Gui [ kkd: Split update and delete coverage and rewrote the commit log ] Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904104203.345917-5-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- 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