selftests/bpf: Check that JMP32 pointer vs zero jumps are not predictedgrafted

Add jmp32_ptr_vs_zero_jne: the fall-through of the 32-bit compare, which
the verifier used to skip, contains an out of bounds map value access,
hence w/o the previous patch the program is accepted. See previous patch
for detailed description.

Reported-by: Nicholas Carlini <npc@anthropic.com>
Suggested-by: Nicholas Carlini <npc@anthropic.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260904083325.2083493-6-eddyz87@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/tools/bootconfig/Makefile b/tools/bootconfig/Makefile
new file mode 100644
index 000000000..90eb47c9d
--- /dev/null
+++ b/tools/bootconfig/Makefile
@@ -0,0 +1,30 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for bootconfig command
+include ../scripts/Makefile.include
+
+bindir ?= /usr/bin
+
+ifeq ($(srctree),)
+srctree := $(patsubst %/,%,$(dir $(CURDIR)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+endif
+
+LIBSRC = $(srctree)/lib/bootconfig.c $(srctree)/include/linux/bootconfig.h
+override CFLAGS += -Wall -g -I$(CURDIR)/include
+
+ALL_TARGETS := bootconfig
+ALL_PROGRAMS := $(patsubst %,$(OUTPUT)%,$(ALL_TARGETS))
+
+all: $(ALL_PROGRAMS) test
+
+$(OUTPUT)bootconfig: main.c include/linux/bootconfig.h $(LIBSRC)
+	$(CC) $(filter %.c,$^) $(CFLAGS) $(LDFLAGS) -o $@
+
+test: $(ALL_PROGRAMS) test-bootconfig.sh
+	./test-bootconfig.sh $(OUTPUT)
+
+install: $(ALL_PROGRAMS)
+	install $(OUTPUT)bootconfig $(DESTDIR)$(bindir)
+
+clean:
+	$(RM) -f $(OUTPUT)*.o $(ALL_PROGRAMS)