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/Makefile.asm-headers | 105 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 105 insertions(+) create mode 100644 scripts/Makefile.asm-headers (limited to 'scripts/Makefile.asm-headers') diff --git a/scripts/Makefile.asm-headers b/scripts/Makefile.asm-headers new file mode 100644 index 000000000..f1c3d287c --- /dev/null +++ b/scripts/Makefile.asm-headers @@ -0,0 +1,105 @@ +# SPDX-License-Identifier: GPL-2.0 +# include/asm-generic contains a lot of files that are used +# verbatim by several architectures. +# +# This Makefile generates arch/$(SRCARCH)/include/generated/(uapi/)/asm +# headers from multiple sources: +# - a small wrapper to include the corresponding asm-generic/*.h +# is generated for each file listed as generic-y +# - uapi/asm/unistd_*.h files listed as syscalls-y are generated from +# syscall.tbl with the __NR_* macros +# - Corresponding asm/syscall_table_*.h are generated from the same input + +PHONY := all +all: + +src := $(srctree)/$(subst /generated,,$(obj)) + +syscall_abis_32 += common,32 +syscall_abis_64 += common,64 +syscalltbl := $(srctree)/scripts/syscall.tbl +syshdr-args := --emit-nr + +# let architectures override $(syscall_abis_%) and $(syscalltbl) +-include $(srctree)/arch/$(SRCARCH)/kernel/Makefile.syscalls +include $(srctree)/scripts/Kbuild.include +-include $(kbuild-file) + +syshdr := $(srctree)/scripts/syscallhdr.sh +systbl := $(srctree)/scripts/syscalltbl.sh + +# $(generic)/Kbuild lists mandatory-y. Exclude um since it is a special case. +ifneq ($(SRCARCH),um) +include $(srctree)/$(generic)/Kbuild +endif + +redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y)) +redundant += $(foreach f, $(generic-y), $(if $(wildcard $(src)/$(f)),$(f))) +redundant := $(sort $(redundant)) +$(if $(redundant),\ + $(warning redundant generic-y found in $(src)/Kbuild: $(redundant))) + +# If arch does not implement mandatory headers, fallback to asm-generic ones. +mandatory-y := $(filter-out $(generated-y), $(mandatory-y)) +generic-y += $(foreach f, $(mandatory-y), $(if $(wildcard $(src)/$(f)),,$(f))) + +generic-y := $(addprefix $(obj)/, $(generic-y)) +syscall-y := $(addprefix $(obj)/, $(syscall-y)) +generated-y := $(addprefix $(obj)/, $(generated-y)) + +# Remove stale wrappers when the corresponding files are removed from generic-y +old-headers := $(shell test -d $(obj) && find $(obj) -name '*.h' ! -name '.*') +unwanted := $(filter-out $(generic-y) $(generated-y) $(syscall-y),$(old-headers)) + +filechk_wrap = echo "\#include " + +quiet_cmd_remove = REMOVE $(unwanted) + cmd_remove = rm -f $(unwanted); find $(obj) -type d -empty -delete + +quiet_cmd_syshdr = SYSHDR $@ + cmd_syshdr = $(CONFIG_SHELL) $(syshdr) \ + $(if $(syshdr-args-$*),$(syshdr-args-$*),$(syshdr-args)) \ + $(if $(syscall_compat),--prefix "compat$*_") \ + --abis $(subst $(space),$(comma),$(strip $(syscall_abis_$*))) \ + $< $@ + +quiet_cmd_systbl = SYSTBL $@ + cmd_systbl = $(CONFIG_SHELL) $(systbl) \ + $(if $(systbl-args-$*),$(systbl-args-$*),$(systbl-args)) \ + --abis $(subst $(space),$(comma),$(strip $(syscall_abis_$*))) \ + $< $@ + +all: $(generic-y) $(syscall-y) + $(if $(unwanted),$(call cmd,remove)) + @: + +$(obj)/%.h: $(srctree)/$(generic)/%.h FORCE + $(call filechk,wrap) + +$(obj)/unistd_%.h: $(syscalltbl) $(syshdr) FORCE + $(call if_changed,syshdr) + +$(obj)/unistd_compat_%.h: syscall_compat:=1 +$(obj)/unistd_compat_%.h: $(syscalltbl) $(syshdr) FORCE + $(call if_changed,syshdr) + +$(obj)/syscall_table_%.h: $(syscalltbl) $(systbl) FORCE + $(call if_changed,systbl) + +targets := $(syscall-y) + +# Create output directory. Skip it if at least one old header exists +# since we know the output directory already exists. +ifeq ($(old-headers),) +$(shell mkdir -p $(obj)) +endif + +PHONY += FORCE + +FORCE: + +existing-targets := $(wildcard $(sort $(targets))) + +-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) + +.PHONY: $(PHONY) -- cgit v1.3.1